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May 2016
@sandimetz
Sandi Metz
Get a Whiff
of This
Sandi Metz
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@sandimetz May 2016
Kent Beck
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@sandimetz May 2016
Kent Beck Martin Fowler
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@sandimetz May 2016
Kent Beck Martin Fowler
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@sandimetz May 2016
Classic Smells
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@sandimetz May 2016
Classic Smells
Alternative Classes
w/ Different Interfaces
Comments
Data Class
Data Clumps
Divergent Change
Duplicated Code
Feature Envy
Parallel Inheritance
Hierarchies
Primitive Obsession
Refused Bequest
Shotgun Surgery
Speculative Generality
Switch Statements
Temporary Field
Inappropriate Intimacy
Incomplete Library Client
Large Class
Long Method
Long Parameter List
Message Chains
Middle Man
Lazy Class
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@sandimetz May 2016
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Slide 8 text
@sandimetz May 2016
Alternative Classes
w/ Different Interfaces
Comments
Data Class
Data Clumps
Divergent Change
Duplicated Code
Feature Envy
Parallel Inheritance
Hierarchies
Primitive Obsession
Refused Bequest
Shotgun Surgery
Speculative Generality
Switch Statements
Temporary Field
Classic Smells
Inappropriate Intimacy
Incomplete Library Client
Large Class
Long Method
Long Parameter List
Message Chains
Middle Man
Lazy Class
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@sandimetz May 2016
Alternative Classes
w/ Different Interfaces
Comments
Data Class
Data Clumps
Divergent Change
Duplicated Code
Feature Envy
Parallel Inheritance
Hierarchies
Primitive Obsession
Refused Bequest
Shotgun Surgery
Speculative Generality
Switch Statements
Temporary Field
Classic Smells
Inappropriate Intimacy
Incomplete Library Client
Long Method
Long Parameter List
Message Chains
Middle Man
Lazy Class
Large Class
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@sandimetz May 2016
Alternative Classes
w/ Different Interfaces
Data Class
Data Clumps
Divergent Change
Duplicated Code
Feature Envy
Parallel Inheritance
Hierarchies
Primitive Obsession
Refused Bequest
Shotgun Surgery
Speculative Generality
Switch Statements
Temporary Field
Classic Smells
Inappropriate Intimacy
Long Method
Long Parameter List
Message Chains
Middle Man
Lazy Class
Large Class
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@sandimetz May 2016
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
Data Class
Duplicated Code
Speculative Generality
Lazy Class
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
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@sandimetz May 2016
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
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@sandimetz May 2016
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
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@sandimetz May 2016
Bloaters
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
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@sandimetz May 2016
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
Data Class
Duplicated Code
Speculative Generality
Lazy Class
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
Bloaters
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@sandimetz May 2016
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
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@sandimetz May 2016
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
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@sandimetz May 2016
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
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@sandimetz May 2016
Tool Abusers
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
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@sandimetz May 2016
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
Data Class
Duplicated Code
Speculative Generality
Lazy Class
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
Bloaters
Abusers
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
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@sandimetz May 2016
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
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@sandimetz May 2016
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
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@sandimetz May 2016
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
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@sandimetz May 2016
Change Preventers
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
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@sandimetz May 2016
Data Class
Duplicated Code
Speculative Generality
Lazy Class
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
Bloaters
Abusers
Preventers
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@sandimetz May 2016
Data Class
Duplicated Code
Speculative Generality
Lazy Class
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@sandimetz May 2016
Data Class
Duplicated Code
Speculative Generality
Lazy Class
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@sandimetz May 2016
Data Class
Duplicated Code
Speculative Generality
Lazy Class
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@sandimetz May 2016
Dispensables Data Class
Duplicated Code
Speculative Generality
Lazy Class
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@sandimetz May 2016
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
Data Class
Duplicated Code
Speculative Generality
Lazy Class
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
Bloaters
Abusers
Preventers
Dispensables
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@sandimetz May 2016
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
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@sandimetz May 2016
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
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@sandimetz May 2016
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
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@sandimetz May 2016
Couplers
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
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@sandimetz May 2016
Feature Envy
Inappropriate Intimacy
Message Chains
Middle Man
Data Class
Duplicated Code
Speculative Generality
Lazy Class
Divergent Change
Parallel Inheritance
Hierarchies
Shotgun Surgery
Alternative Classes
w/ Different Interfaces
Refused Bequest
Switch Statements
Temporary Field
Data Clumps
Primitive Obsession
Long Method
Long Parameter List
Large Class
Bloaters
Abusers
Preventers
Dispensables
Couplers
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@sandimetz May 2016
Refactoring
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@sandimetz May 2016
Refactoring Recipe
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@sandimetz May 2016
Fowler 149:
Extract Class
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@sandimetz May 2016
Refactoring Recipe
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@sandimetz May 2016
Code Smell
Curative Refactoring Recipe
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@sandimetz May 2016
http://www.industriallogic.com/wp-content/uploads/2005/09/smellstorefactorings.pdf
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@sandimetz May 2016
http://www.industriallogic.com/wp-content/uploads/2005/09/smellstorefactorings.pdf
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@sandimetz May 2016
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@sandimetz May 2016
1
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@sandimetz May 2016
class Sale < Persistence
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
Slide 66
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
Slide 67
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
Kaboom
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Larry
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Curly
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Mo
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Larry
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Curly
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Mo
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Fee
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Fi
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Foe
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Larry
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Curly
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Mo
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Fee
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Fi
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Foe
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
2
Data Clump | Extract Class
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@sandimetz May 2016
class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class Sale < Persistence
end
class Expense < Persistence
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Foo
def sales_total(params)
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Bar
def weekly_sales_total(params)
start_date = (Date.parse(params[:starting]))
end_date = start_date + 6
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Bar
def weekly_sales_total(params)
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: (start_date..end_date)).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Baz
def expense_total(params)
start_date = (Date.parse(params[:starting])) rescue Date.today
end_date = (Date.parse(params[:ending])) rescue start_date
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Baz
def expense_total(params)
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: (Date.parse(params[:starting]))..(Date.parse(params[:ending]))).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
Data Clump | Extract Class
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@sandimetz May 2016
3
Message Chain | Hide Delegate
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@sandimetz May 2016
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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Foo
Sale.where(date: range).sum("cost")
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Foo Sale
Sale.where(date: range).sum("cost")
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Foo Sale
where
Sale.where(date: range).sum("cost")
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Foo Sale
Persistence
where
Sale.where(date: range).sum("cost")
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Foo Sale
Persistence
where
where
Sale.where(date: range).sum("cost")
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Persistence
where
where
Sale.where(date: range).sum("cost")
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Foo Sale
Persistence
where
where
List
Sale.where(date: range).sum("cost")
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Foo Sale
Persistence
where
where
List
Sale.where(date: range).sum("cost")
??? ??? ???
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Foo Sale
Persistence
where
where
List
Sale.where(date: range).sum("cost")
??? ??? ???
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Foo Sale
Persistence
where
where
List
Sale.where(date: range).sum("cost")
??? ??? ???
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Foo Sale
Persistence
where
where
List
a list
Sale.where(date: range).sum("cost")
??? ??? ???
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Foo Sale
Persistence
where
where
List
a list
a list
Sale.where(date: range).sum("cost")
??? ??? ???
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Foo Sale
Persistence
where
where
List
sum
a list
a list
Sale.where(date: range).sum("cost")
??? ??? ???
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Foo
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DateRange
Foo
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Sale
#where
DateRange
Foo
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Sale
#where
DateRange
Foo
Immediate Collaborators
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List
#sum
Sale
#where
DateRange
Foo
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List
#sum
Sale
#where
DateRange
Foo
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#sum
Sale
#where
DateRange
Foo
Sale.where(date: range).sum("cost")
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List
#sum
Sale
#where
DateRange
Foo
I know my collaborators collaborators
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List
#sum
Sale
#where
DateRange
Foo
This is gonna hurt
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@sandimetz May 2016
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.where(date: range).sum("cost")
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
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class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.where(date: range).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
class Bar
def weekly_sales_total(params)
range = DateRange.new(starting: params[:starting]).week_range
Sale.total(within: range)
end
end
class Baz
def expense_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Expense.total(within: range)
end
end
Message Chain | Hide Delegate
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@sandimetz May 2016
4
Sidebar: How Much Reality?
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
Check the query result
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
Depend on Sale class?
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
Depend on Totalizable role!
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
Sale.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
Two players of the Totalizable role
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class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
assert_equal 28, Foo.new.sales_total(starting: "2016-04-01", ending: "2016-04-07")
end
end
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class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
assert_equal 28, Foo.new.sales_total(params)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
model = TotalizableDouble
assert_equal 28, Foo.new.sales_total(params)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
model = TotalizableDouble
assert_equal 28, Foo.new.sales_total(params)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
model = TotalizableDouble
assert_equal 28, Foo.new.sales_total(params, model)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
model = TotalizableDouble
assert_equal 28, Foo.new.sales_total(params, model)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
model = TotalizableDouble
assert_equal 47, Foo.new.sales_total(params, model)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
model = TotalizableDouble
assert_equal 47, Foo.new.sales_total(params, model)
end
end
FAST
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# Slow Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
model = TotalizableDouble
assert_equal 47, Foo.new.sales_total(params, model)
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
# FAST Test
class TotalizableDouble
def self.total(within:)
47
end
end
class FooTest < Minitest::Test
def test_sales_total
params = {:starting => "2016-04-01", :ending => "2016-04-07"}
model = TotalizableDouble
assert_equal 47, Foo.new.sales_total(params, model)
end
end
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@sandimetz May 2016
5
Duplicated Code | Pull Up Method
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
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@sandimetz May 2016
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
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module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
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module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
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module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
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module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
Speculative Generality
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module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
class Expense < Persistence
def self.total(within:)
where(date: within).sum("cost")
end
end
Dependency Injection
Is
Awesome
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@sandimetz May 2016
module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
end
class Expense < Persistence
end
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module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
extend Totalable
end
class Expense < Persistence
extend Totalable
end
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@sandimetz May 2016
module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
extend Totalable
end
class Expense < Persistence
extend Totalable
end
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@sandimetz May 2016
module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
extend Totalable
end
class Expense < Persistence
extend Totalable
end
Duplicated Code | Pull Up Method
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@sandimetz May 2016
Code Smell
Curative Refactoring Recipe
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@sandimetz May 2016
class DateRange
attr_reader :starting, :ending
def initialize(starting:, ending: nil)
@starting = Date.parse(starting) rescue Date.today
@ending = Date.parse(ending) rescue @starting
end
def range
starting..ending
end
def week_range
starting..(starting + 6)
end
end
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@sandimetz May 2016
module Totalable
def total(within:, date_field: :date, on: "cost")
where({date_field => within}).sum(on)
end
end
class Sale < Persistence
extend Totalable
end
class Expense < Persistence
extend Totalable
end
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class Foo
def sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
class Bar
def weekly_sales_total(params, model=Sale)
range = DateRange.new(starting: params[:starting]).week_range
model.total(within: range)
end
end
class Baz
def expense_total(params, model=Expense)
range = DateRange.new(starting: params[:starting], ending: params[:ending]).range
model.total(within: range)
end
end
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Fist Pump
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@sandimetz May 2016
Fist Pump
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@sandimetz May 2016
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@sandimetz May 2016
Reek
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@sandimetz May 2016
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@sandimetz
Thanks
May 2016
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@sandimetz
References
May 2016
http://martinfowler.com/books/refactoring.html
http://www.refactoringinruby.info/ Kevin Rutherford, William Wake
Mäntylä, M. V. and Lassenius, C. "Subjective Evaluation of Software Evolvability Using Code Smells: An
Empirical Study". Journal of Empirical Software Engineering, vol. 11, no. 3, 2006, pp. 395-431.
https://github.com/troessner/reek
https://blog.codeship.com/how-to-find-ruby-code-smells-with-reek
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@sandimetz
Credits
May 2016
Coffee on a Winter's morning, Stefan Lins, https://www.flickr.com/photos/mrlins/8533102693/
Royal Australian Air Force in Australia during World War II, Argus Newspaper Collection of Photographs, State
Library of Victoria, https://www.flickr.com/photos/statelibraryofvictoria_collections/16554906225/
Chevy Crusher, Ruby Eng , https://www.flickr.com/photos/mac-ash/4105522760/
Misuse Makes Mishaps, Jeremy Brooks , https://www.flickr.com/photos/jeremybrooks/2205135193,
resistance is futile, Lora, https://www.flickr.com/photos/laroyo/6871150550/
Well this is pointless, Janet McKnight, https://www.flickr.com/photos/janetmck/2613441853/
Glue goo 3, Sam-Cat, https://www.flickr.com/photos/samcatchesides/3326878644/
poses of victory, Daniel Novta, https://www.flickr.com/photos/vanf/7304661962/
Odorous smells!, auddess, https://www.flickr.com/photos/auddess/4744679975
EXPLORE] Smell the Flowers, Christine und David Schmitt, https://www.flickr.com/photos/cheesy42/8624536219/
PIZZA, Tobi Gaulke. https://www.flickr.com/photos/gato-gato-gato/15958062095/
Ain't Life Grand, Anne Worner, https://www.flickr.com/photos/wefi_official/9305161946/
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@sandimetz
http://poodr.com
May 2016
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@sandimetz
http://99bottlesbook.com
May 2016
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@sandimetz
Sandi Metz
@sandimetz
http://sandimetz.com
May 2016
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@sandimetz
Questions?
May 2016
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@sandimetz
Sandi Metz
@sandimetz
http://sandimetz.com
May 2016