Getting Testy With Raku: Things you wish you knew.

Testing is well integrated into Raku culture, starting with a familiar "Test" module. This talk reviews the basics of testing with "ok" along with data structure issues that affect testing and comparison. The coverage is suitable for someone new to Raku or who wants to improve their testing.

Transcript

1. Getting Testy With Raku: Things you wish you’d known. Steven Lembark Workhorse Computing lembark@wrkhors.com
2. Time passes This talk was given in 2016 on ‘Testing Perl6’. Now it’s “Raku”. Some things have changed.
3. Time passes This talk was given in 2016 on ‘Testing Perl6’. Now it’s “Raku”. Some things have changed. Methods use ‘-’ instead of ‘_’. zef replaced panda. prove6 replaced prove.
4. Time passes This talk was given in 2016 on ‘Testing Perl6’. Now it’s “Raku”. Much of it’s the same. TAP format Test module ok method
5. Few things you need for testing Raku zef prove6 Linenoise An enjoyable liquid...
6. Getting Started # hard to test without raku, though # installation is straightforward git clone \ git://github.com/rakudo/rakudo.git; cd rakudo; less INSTALL.md;
7. Getting Started # hard to test without raku, though. # installation is straightforward. git clone \ git://github.com/rakudo/rakudo.git; cd rakudo; git pull --all; # doc’s describe other choices. perl Configure.pl \ --prefix=/opt/rakudo \ --gen-moar --gen-nqp \ --backends=moar ;
8. Getting Started # eventually... +++ Installing default runner NQP has been built and installed. Using /opt/rakudo/bin/nqp-m (version 2022.12 / MoarVM 2022.12). Cleaning up ... You can now use 'make' to build Rakudo. After that, 'make test' will run some tests and 'make install' will install Rakudo.
9. Getting Started # eventually... +++ Installing default runner NQP has been built and installed. Using /opt/rakudo/bin/nqp-m (version 2022.12 / MoarVM 2022.12). Cleaning up ... You can now use 'make' to build Rakudo. After that, 'make test' will run some tests and 'make install' will install Rakudo.
10. Getting Started make -wk all test install; ... # our first example of Raku tests! t/01-sanity/02-op-math.t ....................... ok t/01-sanity/03-op-logic.t ...................... ok t/01-sanity/04-op-cmp.t ........................ ok t/01-sanity/01-literals.t ...................... ok
11. Getting Started t/06-telemetry/01-basic.t ..................... ok All tests successful. Files=111, Tests=1865, 582 wallclock secs ( 0.57 usr 0.12 sys + 225.93 cusr 22.04 csys = 248.66 CPU) Result: PASS +++ Creating installation directories
12. Getting Started +++ Preparing installation Installed 20 core modules in 10.587543038 seconds! +++ MOAR BACKEND INSTALLED +++ Installing MOAR launchers +++ Creating Raku executable alias +++ Rakudo installed succesfully! make: Leaving directory '/scratch/Build/Raku/rakudo'
13. Getting Started # we will need the package manager: git clone https://github.com/ugexe/zef.git ; cd zef ; less README.md;
14. Getting Started # we will need the package manager: git clone https://github.com/ugexe/zef.git ; cd zef ; raku -I. bin/zef install . ;
15. Getting Started raku -I. bin/zef install . ; ===> Staging zef:ver<0.22.0>:auth<github:ugexe>:api<0> ===> Staging [OK] for zef:ver<0.22.0>:auth<github:ugexe>:api<0> ===> Testing: zef:ver<0.22.0>:auth<github:ugexe>:api<0> ===> Testing [OK] for zef:ver<0.22.0>:auth<github:ugexe>:api<0> ===> Installing: zef:ver<0.22.0>:auth<github:ugexe>:api<0> 1 bin/ script [zef] installed to: /opt/rakudo/share/perl6/site/bin
16. Getting Started # validate zef install, update the libraries, # validate the network connection. zef update ;
17. Getting Started # validate zef install, update the libraries, # validate the network connection. zef update ; ===> Updating fez mirror: https://360.zef.pm/ ===> Updating rea mirror: https://raw.githubusercontent.com/Raku/REA/main/META.json ===> Updated fez mirror: https://360.zef.pm/ ===> Updated rea mirror: https://raw.githubusercontent.com/Raku/REA/main/META.json
18. Getting Started # Linenoise gives command line editing, etc. zef install Linenoise ; ===> Searching for: Linenoise ===> Searching for missing dependencies: LibraryMake ===> Searching for missing dependencies: Shell::Command, File::Which ===> Searching for missing dependencies: File::Find ===> Building: Linenoise:ver<0.1.2>:auth<zef:raku-community-modules>
19. Modules are more specific in Raku! Perl modules are Foo::Bar.
20. Modules are more specific in Raku! Perl modules are Foo::Bar. Raku modules support version owner api
21. Modules are more specific in Raku! Perl modules are Foo::Bar. Raku module with version and author: Linenoise:ver<0.1.2>:auth<zef:raku-community-modules>
22. Modules are more specific in Raku! Perl modules are Foo::Bar. Raku module with version and author: Linenoise:ver<0.1.2>:auth<zef:raku-community-modules> Raku testing may reqire more metadata.
23. Also helps to have prove6 # https://raku.land/cpan:LEONT/App::Prove6 zef install App::Prove6 ;
24. Also helps to have prove6 # install the prove utility zef install App::Prove6 ; ... ===> Installing: App::Prove6:ver<0.0.17>:auth<cpan:LEONT> 1 bin/ script [prove6] installed to: /opt/rakudo/share/perl6/site/bin ===> Installing: App::Prove6:ver<0.0.17>:auth<cpan:LEONT> 1 bin/ script [prove6] installed to: /opt/rakudo/share/perl6/site/bin
25. Also helps to have prove6 # install the prove utility zef install App::Prove6 ; ... ===> Installing: App::Prove6:ver<0.0.17>:auth<cpan:LEONT> 1 bin/ script [prove6] installed to: /opt/rakudo/share/perl6/site/bin ===> Installing: App::Prove6:ver<0.0.17>:auth<cpan:LEONT> 1 bin/ script [prove6] installed to: /opt/rakudo/share/perl6/site/bin
26. Basic Test in Raku Start with Test use Test; my $x = 0; my $y = 'asdf'; ok $x == $y, "$x == $y"; done-testing;
27. Basic Test in Raku Start with Test Test is run with ”ok” as usual. use Test; my $x = 0; my $y = 'asdf'; ok $x == $y, "$x == $y"; done-testing;
28. Basic Test in Raku Start with Test Notice the dash! Raku methods use ‘-’ in their names! use Test; my $x = 0; my $y = 'asdf'; ok $x == $y, "$x == $y"; done-testing;
29. Running the test $ prove6 t/01.t Cannot convert string to number: base-10 number must begin with valid digits or '.' in ' asdf' (indicated by ) ⏏ ⏏ in block <unit> at t/01.t line 6 t/01.t .. Dubious, test returned 1 No subtests run Test Summary Report ------------------- t/01.t (Wstat: 256 Tests: 0 Failed: 0) Non-zero exit status: 1 Parse errors: No plan found in TAP output Files=1, Tests=0, 0 wallclock secs Result: FAILED
30. Running the test $ prove6 t/01.t Cannot convert string to number: base-10 number must begin with valid digits or '.' in ' asdf' (indicated by ) ⏏ ⏏ in block <unit> at t/01.t line 6 my $x = 0; my $y = 'asdf'; ok $x == $y, "$x == $y";
31. Running the test my $x = 0; my $y = 'asdf'; ok $x == $y, "$x == $y"; Lesson: Raku is more type-specific than Perl.
32. Stringy test with Raku “is” does stringy tests. use Test; my $x = '0'; my $y = 'asdf'; is $x, $y, "$x eq $y"; done-testing;
33. Stringy test with Raku $ prove6 t/02.t # Failed test '0 eq asdf' # at t/02.t line 6 # expected: 'asdf' # got: '0' # You failed 1 test of 1 t/02.t .. Dubious, test returned 1 Failed 1/1 subtests Test Summary Report ------------------- t/02.t (Wstat: 256 Tests: 1 Failed: 1) Failed tests: 1 Non-zero exit status: 1 Files=1, Tests=1, 0 wallclock secs Result: FAILED
34. Smarter tests with ~~ Smart-Match finds ‘reasonable’ ways to compare objects. 0 ~~ ‘asdf’ fails gracefully based on the value. use Test; my $x = 0; my $y = 'asdf'; ok $x ~~ $y, "$x ~~ $y"; done-testing;
35. Smarter tests with ~~ $ prove6 t/05.t # Failed test '0 ~~ asdf' # at t/05.t line 6 # You failed 1 test of 1 t/05.t .. Dubious, test returned 1 Failed 1/1 subtests Test Summary Report ------------------- t/05.t (Wstat: 256 Tests: 1 Failed: 1) Failed tests: 1 Non-zero exit status: 1 Files=1, Tests=1, 0 wallclock secs Result: FAILED
36. Introspection in tests “WHAT” returns a type object. use Test; my $x = 0; is $x.WHAT, Int, "$x is Int"; done-testing;
37. Introspection in tests Int is an object, not a string: Notice the lack of quotes. use Test; my $x = 0; is $x.WHAT, Int, "$x is Int"; done-testing;
38. Introspection in tests $ prove6 t/03.t ; t/03.t .. ok All tests successful. Files=1, Tests=1, 0 wallclock secs Result: PASS
39. More introspection with WHICH WHICH identifies the object. use Test; my $x = 0; is $x.WHAT, Int, "$x is Int"; note '$x is ' ~ $x.WHICH; done-testing;
40. More introspection with WHICH $x is an Int object with a value of 0. Output nice for diagnostics. $ prove6 t/04.t $x is Int|0 t/04.t .. ok All tests successful. Files=1, Tests=1, 0 wallclock secs Result: PASS
41. Quick tests in the REPL $ raku; Welcome to Rakudo™ v2022.12. Implementing the Raku® Programming Language v6.d. Built on MoarVM version 2022.12. To exit type 'exit' or '^D' [0] >
42. Quick tests in the REPL [0] > %a = 'a' .. 'e' ; ===SORRY!=== Error while compiling: Variable '%a' is not declared. Perhaps you forgot a 'sub' if this was intended to be part of a signature? ------> <BOL> %a = 'a' .. 'e' ; ⏏ Type what you like.
43. Quick tests in the REPL [0] > %a = 'a' .. 'e' ; ===SORRY!=== Error while compiling: Variable '%a' is not declared. Perhaps you forgot a 'sub' if this was intended to be part of a signature? ------> <BOL> %a = 'a' .. 'e' ; ⏏ Type what you like. Variables must be declared (reverse of ‘perl -d’).
44. Quick tests in the REPL “my ^a = …” has a variable. ‘a’ .. ‘e’ mis-defines the hash: odd elemement count. But what’s in the hash now? [0] > my %a = 'a' .. 'e' ; Odd number of elements found where hash initializer expected: Found 5 (implicit) elements: Last element seen: "e" in block <unit> at <unknown file> line 1
45. Quick tests in the REPL WHAT & WHICH to the rescue. %a is defined – we have a hash. %a is empty due to the assignment error: No partitial assignment or empty value. [1] > say %a.WHAT; (Hash) [1] > say %a.WHICH; Hash|2999974115968 [1] > say %a; {}
46. Comparing objects: Content vs. Identity Assign %b from %a: Separate objects. Equal contents. > my %a = ( 'a' .. 'd' ); {a => b, c => d} > my %b = %a; {a => b, c => d}
47. Comparing objects: Content vs. Identity Assign %b from %a: Separate objects. Equal contents. > my %a = ( 'a' .. 'd' ); {a => b, c => d} > my %b = %a; {a => b, c => d}
48. Comparing objects: Content vs. Identity Compare Contents > my %a = ( 'a' .. 'd' ); {a => b, c => d} > my %b = %a; {a => b, c => d} > ok %a == %b; ok 1 -
49. Comparing objects: Content vs. Identity > my %a = ( 'a' .. 'd' ); {a => b, c => d} > my %b = %a; {a => b, c => d} > ok %a eq %b; ok 2 - Compare Contents
50. Comparing objects: Content vs. Identity > my %a = ( 'a' .. 'd' ); {a => b, c => d} > my %b = %a; {a => b, c => d} > ok %a ~~ %b; ok 3 - Compare Contents
51. Comparing objects: Content vs. Identity > my %a = ( 'a' .. 'd' ); {a => b, c => d} > my %b = %a; {a => b, c => d} > is %a, %b; ok 4 - Compare Contents
52. Comparing objects: Content vs. Identity > my %a = ( 'a' .. 'd' ); {a => b, c => d} > my %b = %a; {a => b, c => d} > ok %a === %b; not ok 5 - # Failed test at... > %a.WHICH Hash|6519650522896 > %b.WHICH Hash|6519768615264 Compare objects.
53. Comparing objects vs. containers Value vs Non-value: Values: contents Containers: .WHICH == Contents === .WHICH my $a = 42; my $b = 42; my %a = { ‘a’ .. ‘z’ }; my $b = { ‘a’ .. ‘z’ }; $a === $b 42 == 42 true %a === $b %a.WHICH == $b.WHICH false
54. Hashes don’t ‘flatten’ my %a = ( 'a' .. 'd' ); my @b = %a; my @c = ( 'a' .. 'd' ); +> dd %a, @b, @c Hash %a = {:a("b"), :c("d")} Array @b = [:a("b"), :c("d")] Array @c = ["a", "b", "c", "d"]
55. Hashes don’t ‘flatten’ my %a = ( 'a' .. 'd' ); my @b = %a; my @c = ( 'a' .. 'd’ ); +> dd %a, @b, @c Hash %a = {:a("b"), :c("d")} Array @b = [:a("b"), :c("d")] <-- pairs! Array @c = ["a", "b", "c", "d"]
56. Comparing constants Some things like “Bag” are immutable. These will share a WHICH value. True with '===' (identity) False with '=:=' (object id)
57. Bags are immutable > my @a = ( 'a', 'b', 'c', '', 'c', 'c' ); [a b c b c c] > my $b = @a.Bag; bag(a, c(3), b(2)) > my $c = @a.Bag; bag(a, c(3), b(2))
58. Bags are immutable > @a.WHICH; Array|162386224 > $b.WHICH; Bag|Str|a(1) Str|b(2) Str|c(3) > $c.WHICH; Bag|Str|a(1) Str|b(2) Str|c(3) > my @a = ( 'a', 'b', 'c', '', 'c', 'c' ); [a b c b c c] > my $b = @a.Bag; bag(a, c(3), b(2)) > my $c = @a.Bag; bag(a, c(3), b(2))
59. Bags are immutable > @a.WHICH; Array|162386224 > $b.WHICH; Bag|Str|a(1) Str|b(2) Str|c(3) > $c.WHICH; Bag|Str|a(1) Str|b(2) Str|c(3) > my @a = ( 'a', 'b', 'c', '', 'c', 'c' ); [a b c b c c] > my $b = @a.Bag; bag(a, c(3), b(2)) > my $c = @a.Bag; bag(a, c(3), b(2)) > $b === $c # contents True
60. Bags are immutable > @a.WHICH; Array|162386224 > $b.WHICH; Bag|Str|a(1) Str|b(2) Str|c(3) > $c.WHICH; Bag|Str|a(1) Str|b(2) Str|c(3) > my @a = ( 'a', 'b', 'c', '', 'c', 'c' ); [a b c b c c] > my $b = @a.Bag; bag(a, c(3), b(2)) > my $c = @a.Bag; bag(a, c(3), b(2)) > $b === $c # contents True > $b =:= $c # objects False
61. Multimetods allow various comparisons “eqv” used to compare objects. This is an operator: multi infix: <eqv> ( Foo $x, Bar $y ) Classes can supply their own. Tests can override them.
62. Multimetods allow various comparisons Compare to an Int: multi infix: <eqv> ( MyClass $a, Int $b ) { ... } Compare undefined value: multi infix: <eqv> (MyClass:U $a, Mu $b) { fail “Undefined MyClass Object” }
63. Have it your way... Is-deeply uses its own eqv. cmp-ok uses yours: cmp-ok $found, 'eqv', $expect; cmp-ok $found, 'oneshot', $expect;
64. Approximate testing Absolute, relative tolerance to expect. Uses eqv, requires same types. Really nice for geo-coding, physical data: my $abs-tol = 0.0005; is-approx $lat, $exp, :$abs-tol;
65. Summary Testing is a bit more precise in Raku than Perl: Strong types == vs. === vs. =:= And more flexible: == vs. eq vs. ~~ vs. eqv Pay attention to underlying types: hashes don’t ‘flatten’, bags are immutable.
66. References https://docs.raku.org/language/testing