Re: [PATCH 03/10] t4018: an infrastructure to test hunk headers

[Junio C Hamano <gitster@pobox.com>]

Johannes Sixt <j6t@kdbg.org> writes:

> Add an infrastructure that simplifies adding new tests of the hunk
> header regular expressions.
>
> To add new tests, a file with the syntax to test can be dropped in the
> directory t4018. The README file explains how a test file must contain;

s/how/what/, or "how a test file must be written" you mean?

> the README itself tests the default behavior.

Thanks.  Looks like a reasonable way to mark what must be found.

> Signed-off-by: Johannes Sixt <j6t@kdbg.org>
> ---
>  t/t4018-diff-funcname.sh | 60 +++++++++++++++++++++++++++++++++++++++++++-----
>  t/t4018/README           | 18 +++++++++++++++
>  2 files changed, 72 insertions(+), 6 deletions(-)
>  create mode 100644 t/t4018/README
>
> diff --git a/t/t4018-diff-funcname.sh b/t/t4018-diff-funcname.sh
> index 38a092a..b467d9e 100755
> --- a/t/t4018-diff-funcname.sh
> +++ b/t/t4018-diff-funcname.sh
> @@ -100,7 +100,25 @@ test_expect_funcname () {
>  	grep "^@@.*@@ $1" diff
>  }
>  
> -for p in ada bibtex cpp csharp fortran html java matlab objc pascal perl php python ruby tex
> +diffpatterns="
> +	ada
> +	bibtex
> +	cpp
> +	csharp
> +	fortran
> +	html
> +	java
> +	matlab
> +	objc
> +	pascal
> +	perl
> +	php
> +	python
> +	ruby
> +	tex
> +"
> +
> +for p in $diffpatterns
>  do
>  	test_expect_success "builtin $p pattern compiles" '
>  		echo "*.java diff=$p" >.gitattributes &&

I always found this "Let's apply rules for language $p to these
*.java files" strange.  I have wonder if it makes sense to further
change the framework to read the name of the rule to be applied from
the file in t/t4018/ directory, instead of using filename that is
the same as the name of the rule?  That way, you can list the files
in t/t4018/ directory to come up with the above list, without having
to maintain the list of rules separately like the above.

> @@ -118,11 +136,6 @@ do
>  	'
>  done
>  
> -test_expect_success 'default behaviour' '
> -	rm -f .gitattributes &&
> -	test_expect_funcname "public class Beer\$"
> -'
> -
>  test_expect_success 'set up .gitattributes declaring drivers to test' '
>  	cat >.gitattributes <<-\EOF
>  	*.java diff=java
> @@ -182,4 +195,39 @@ test_expect_success 'alternation in pattern' '
>  	test_expect_funcname "public static void main("
>  '
>  
> +test_expect_success 'setup hunk header tests' '
> +	for i in $diffpatterns
> +	do
> +		echo "$i-* diff=$i"
> +	done > .gitattributes &&

I like that you can have more than one test for each language/rule
this way, allowing you to test one kind of breakage without getting
affected by lines prepared for other tests in the same file.

> +	# add all test files to the index
> +	(
> +		cd "$TEST_DIRECTORY"/t4018 &&
> +		git --git-dir="$TRASH_DIRECTORY/.git" add .
> +	) &&
> +
> +	# place modified files in the worktree
> +	for i in $(git ls-files)
> +	do
> +		sed -e "s/ChangeMe/IWasChanged/" <"$TEST_DIRECTORY/t4018/$i" >"$i" || return 1
> +	done
> +'
> +
> +# check each individual file
> +for i in $(git ls-files)
> +do
> +	if grep broken "$i" >/dev/null 2>&1
> +	then
> +		result=failure
> +	else
> +		result=success
> +	fi
> +	test_expect_$result "hunk header: $i" "
> +		test_when_finished 'cat actual' &&	# for debugging only
> +		git diff -U1 $i >actual &&
> +		grep '@@ .* @@.*RIGHT' actual
> +	"
> +done
> +
>  test_done
> diff --git a/t/t4018/README b/t/t4018/README
> new file mode 100644
> index 0000000..283e01cc
> --- /dev/null
> +++ b/t/t4018/README
> @@ -0,0 +1,18 @@
> +How to write RIGHT test cases
> +=============================
> +
> +Insert the word "ChangeMe" (exactly this form) at a distance of
> +at least two lines from the line that must appear in the hunk header.
> +
> +The text that must appear in the hunk header must contain the word
> +"right", but in all upper-case, like in the title above.
> +
> +To mark a test case that highlights a malfunction, insert the word
> +BROKEN in all lower-case somewhere in the file.
> +
> +This text is a bit twisted and out of order, but it is itself a
> +test case for the default hunk header pattern. Know what you are doing
> +if you change it.
> +
> +BTW, this tests that the head line goes to the hunk header, not the line
> +of equal signs.