The art of deleting code

The art of
deleting
code

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The art of
code
🧘

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The art of
code
✂

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1. Recognize
2. Conﬁrm
3. Share
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The art of deleting code

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Recognize code that can be deleted
def modal(options = {})
options[:button_style] ||= 'primary'
if options[:header_icon]
options[:icon] = icon options[:header_icon]
end
render 'util/modal', options: options
end
A simple snippet of Ruby code

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end
end
A sense of curiosity and wonder
🤔

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Find in Project / awk / grep

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Conﬁrm the code can be deleted
end
end
80b1045 Jim S. 2016-12-13 1)
3348fb2 Amy G. 2019-02-09 2)
3348fb2 Amy G. 2019-02-09 3)
27bedae Liza Q. 2018-03-21 4)
3348fb2 Amy G. 2019-02-09 5)
27bedae Liza Q. 2018-03-21 6)
27bedae Liza Q. 2018-03-21 7)
3348fb2 Amy G. 2019-02-09 8)
80b1045 Jim S. 2016-12-13 9)
git blame ﬁle

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27beda180 create an icon helper (3 years, 6 months ago, Liza Q.)
diff --git app/helpers/util_helper.rb
options[:confirm_button_style] ||= 'primary'
+ if options[:header_icon]
+ options[:header_icon] = icon(options[:header_icon], class: 'margin-r-1-2')
+ end
+
diff --git app/views/delete_app.html.erb
- <%= modal(confirm_button_style: 'warning') do %>
+ <%= modal(confirm_button_style: 'warning', header_icon: 'warning') do %>
Delete this app
git show SHA

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git log ﬁle
git log app/views/delete_app.html.erb
fatal: ambiguous argument 'app/views/delete_app.html.erb':
unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git [...] -- [...]'

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git log ﬁle
'git [...] -- [...]'
git log --follow -- app/views/delete_app.html.erb
86eba3127 Remove the delete app card and modal (2 years, 6 months ago, Mike C.)
650365ba2 Alphabetize the args (3 years, 5 months ago, Joan A.)
………

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Share knowledge about the deletion
git commit
commit a37b6725
Date: Wed Jan 13 10:24:39 2021 -0800
✂ Remove unused option header_icon
It was introduced in 27beda180 but its last invocation was removed in 86eba3127.
- if options[:header_icon]
- options[:header_icon] = icon(options[:header_icon], class: 'margin-r-1-2')
- end
-

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git stash
git status
Changes not staged for commit:
modified: app/helpers/util_helper.rb
Untracked files:
app/views/add_app.html.erb

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git stash
git status
Untracked files:
git stash --include-untracked
Saved working directory and index state WIP on feature_branch: 073a5e03f

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git stash
git status
Untracked files:
Saved working directory and index state WIP on feature_branch: 073a5e03f
git stash apply

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1. Recognize
2. Conﬁrm
3. Share
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Code coverage beyond testing

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git log ﬁle
🤔
'git [...] -- [...]'
git log --follow -- app/views/delete_app.html.erb
86eba3127 Remove the delete app card and modal (2 years, 6 months ago, Mike C.)
………

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git log ﬁle
957e23451 Alphabetize the method arguments (3 days ago, Joan A.)
0f14cf51e HTML cleanup (4 months ago, Joan A.)
a3c92896c Fix the link to embedded apps(6 months ago, Mike C.)
81634ab2a Remove app feature flag (7 months ago, Sarah K.)
1054bcb23 add a dedicated component (8 months ago, Sarah K.)
(dozens of other commits)
b921b4e05 Add metrics show page (2 years, 9 months ago, Sam P.)
5c177ca9c Move endpoint under app (3 years, 1 month ago, Joan A.)

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git log ﬁle
The code was
added here

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git log ﬁle
The code is not
there anymore
The code was
added here

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git log ﬁle
The code is not
there anymore
The code was
added here
Which commit
removed it?

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git bisect
git bisect start git log app/views/delete_app.html.erb
957e23451 Alphabetize the method arguments
0f14cf51e HTML cleanup
a3c92896c Fix the link to embedded apps
81634ab2a Remove app feature flag
1054bcb23 Fix typo
1054bcb23 Remove alternate versionable flow
5c177ca9c Move endpoint under app
9203e6345 Remove i18n strings
45629435c Make Rubocop happy
909345aac Fix validation name
77346234b Merge pull request #1296
192837492 Added new section for resource
772934ded Add better validation message
dad734de3 Cleanup comments
98934dcdd Validate schema
012934dcd Inject UID component
bbe364bbd Correct typo in app scope
b763748bd Add indices and sorting
8dcd51283 Merge pull request #1212
9093461ca Change reference to app
883945671 Hound happiness
09087ede5 Remove URL field
7722ded56 More testing
888ddaa12 Make Hound happy
93467cd3d Add info to metadata
912734823 Remove website field
192734cdc Refactor form
812673dc8 Remove UID component
93435aa23 Add internationalization to views
734563cdc Refactor
99d6253dd Apply CSS framework changes
9aaab4344 Fix notification
81002123a Enhance styling of views
acd41623d WIP
28495cdc1 Merge pull request #1001
28945c1ca Remove single quotes
94578694a Initial tweaks for update
1276384cd Add help text
3657831ac Merge pull request #912
447651234 Add frozen string comment
4890dedac Add feature flag
650365ba2 Alphabetize the args
27beda180 create an icon helper

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git bisect
git bisect start
git bisect good 27beda180
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git bisect
git bisect start
git bisect bad 957e23451
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git bisect
git bisect start
Bisecting: 21 revisions left to test (roughly 5 steps)
[09087ede5] Remove URL field
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git bisect
git bisect start
grep -c header_icon app/views/delete_app.html.erb
0
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git bisect
git bisect start
0
git bisect bad
[81002123a] Enhance styling of views
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git bisect
git bisect start
git bisect bad 09087ede5
[81002123a] Enhance styling of views
1
git bisect good
[192734cdc] Refactor form
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git bisect
git bisect start
git bisect good 81002123a
git bisect bad 09087ede5
[192734cdc] Refactor form
0
git bisect bad
[93435aa23] Add internationalization to views
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git bisect
git bisect start
git bisect bad 192734cdc
[93435aa23] Add internationalization to views
1
git bisect good
Bisecting: 1 revisions left to test (roughly 1 step)
[812673dc8] Remove UID component
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git bisect
git bisect start
git bisect bad 192734cdc
Bisecting: 1 revisions left to test (roughly 1 step)
[812673dc8] Remove UID component
1
git bisect good
192734cdc is the first bad commit
git bisect reset
1054bcb23 Fix typo
734563cdc Refactor
acd41623d WIP

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git commit
commit a37b6725
Date: Wed Jan 13 10:24:39 2021 -0800
✂ Remove unused option header_icon
It was introduced in 27beda180 but its last invocation was removed in 192734cdc.
- if options[:header_icon]
- options[:header_icon] = icon(options[:header_icon], class: 'margin-r-1-2')
- end
-

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git blame [file]
When and why was this code added?
git show [commit SHA]
What other code was added at the same time?
git log --follow -- [file]
How was the other code changed over time?
git bisect start/good/bad/reset
What is the relevant change that justifies
the deletion?
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A list of helpful git commands
Pause your current feature work
git commit
Write a meaningful message that includes all
the relevant SHA to help the reviewers
git stash apply
Resume your current feature work

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The art of
code
❤

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The art of
deleting
code

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The art of deleting code

The art of deleting code

Claudio B.

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