Re: [PATCH 09/19] mingw: accomodate t0060-path-utils for MSYS2

From: Johannes Sixt <j6t@kdbg.org>
Date: Jan 24, 2016, 19:51 UTC
Message-ID: <56A52B28.8010304@kdbg.org>
In-Reply-To: <12c030323940de4a0845eda9bdd7b67c4e90864a.1453650173.git.johannes.schindelin@gmx.de>

Am 24.01.2016 um 16:44 schrieb Johannes Schindelin:

Show 49 quoted lines

> On Windows, there are no POSIX paths, only Windows ones (an absolute
> Windows path looks like "C:\Program Files\Git\ReleaseNotes.html", under
> most circumstances, forward slashes are also allowed and synonymous to
> backslashes).
> 
> So when a POSIX shell (such as MSYS2's Bash, which is used by Git for
> Windows to execute all those shell scripts that are part of Git) passes
> a POSIX path to test-path-utils.exe (which is not POSIX-aware), the path
> is translated into a Windows path. For example, /etc/profile becomes
> C:/Program Files/Git/etc/profile.
> 
> This path translation poses a problem when passing the root directory as
> parameter to test-path-utils.exe, as it is not well defined whether the
> translated root directory should end in a slash or not. MSys1 stripped
> the trailing slash, but MSYS2 does not.
> 
> To work with both behaviors, we simply test what the current system does
> in the beginning of t0060-path-utils.sh and then adjust the expected
> longest ancestor length accordingly.
> 
> Originally, the Git for Windows project patched MSYS2's runtime to
> accomodate Git's regression test, but we really should do it the other
> way round.
> 
> Thanks to Ray Donnelly for his patient help with this issue.
> 
> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> ---
>   t/t0060-path-utils.sh | 37 ++++++++++++++++++++++---------------
>   1 file changed, 22 insertions(+), 15 deletions(-)
> 
> diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
> index f0152a7..89d03e7 100755
> --- a/t/t0060-path-utils.sh
> +++ b/t/t0060-path-utils.sh
> @@ -7,6 +7,13 @@ test_description='Test various path utilities'
>   
>   . ./test-lib.sh
>   
> +# On Windows, the root directory "/" is translated into a Windows directory.
> +# As it is not well-defined whether that Windows directory should end in a
> +# slash or not, let's test for that and adjust our expected longest ancestor
> +# length accordingly.
> +root_offset=0
> +case "$(test-path-utils print_path /)" in ?*/) root_offset=-1;; esac
> +
>   norm_path() {
>   	expected=$(test-path-utils print_path "$2")
>   	test_expect_success $3 "normalize path: $1 => $2" \

In t0060-path-utils.sh, I currently find this:

# On Windows, we are using MSYS's bash, which mangles the paths.
# Absolute paths are anchored at the MSYS installation directory,
# which means that the path / accounts for this many characters:
rootoff=$(test-path-utils normalize_path_copy / | wc -c)
# Account for the trailing LF:
if test $rootoff = 2; then
	rootoff=	# we are on Unix
else
	rootoff=$(($rootoff-1))
fi

ancestor() {
	# We do some math with the expected ancestor length.
	expected=$3
	if test -n "$rootoff" && test "x$expected" != x-1; then
		expected=$(($expected+$rootoff))
	fi
	test_expect_success "longest ancestor: $1 $2 => $expected" \
	"actual=\$(test-path-utils longest_ancestor_length '$1' '$2') &&
	 test \"\$actual\" = '$expected'"
}

Furthermore, since you are modifying only cases where the expected value is not -1 and we already have a check for this case in the helper function, wouldn't it be simpler to merge the offset that your case needs with the one that we already have?

Show 47 quoted lines

> @@ -112,30 +119,30 @@ norm_path /d1/.../d2 /d1/.../d2
>   norm_path /d1/..././../d2 /d1/d2
>   
>   ancestor / / -1
> -ancestor /foo / 0
> +ancestor /foo / $root_offset
>   ancestor /foo /fo -1
>   ancestor /foo /foo -1
>   ancestor /foo /bar -1
>   ancestor /foo /foo/bar -1
>   ancestor /foo /foo:/bar -1
> -ancestor /foo /:/foo:/bar 0
> -ancestor /foo /foo:/:/bar 0
> -ancestor /foo /:/bar:/foo 0
> -ancestor /foo/bar / 0
> +ancestor /foo /:/foo:/bar $root_offset
> +ancestor /foo /foo:/:/bar $root_offset
> +ancestor /foo /:/bar:/foo $root_offset
> +ancestor /foo/bar / $root_offset
>   ancestor /foo/bar /fo -1
> -ancestor /foo/bar /foo 4
> +ancestor /foo/bar /foo $((4+$root_offset))
>   ancestor /foo/bar /foo/ba -1
> -ancestor /foo/bar /:/fo 0
> -ancestor /foo/bar /foo:/foo/ba 4
> +ancestor /foo/bar /:/fo $root_offset
> +ancestor /foo/bar /foo:/foo/ba $((4+$root_offset))
>   ancestor /foo/bar /bar -1
>   ancestor /foo/bar /fo -1
> -ancestor /foo/bar /foo:/bar 4
> -ancestor /foo/bar /:/foo:/bar 4
> -ancestor /foo/bar /foo:/:/bar 4
> -ancestor /foo/bar /:/bar:/fo 0
> -ancestor /foo/bar /:/bar 0
> -ancestor /foo/bar /foo 4
> -ancestor /foo/bar /foo:/bar 4
> +ancestor /foo/bar /foo:/bar $((4+$root_offset))
> +ancestor /foo/bar /:/foo:/bar $((4+$root_offset))
> +ancestor /foo/bar /foo:/:/bar $((4+$root_offset))
> +ancestor /foo/bar /:/bar:/fo $root_offset
> +ancestor /foo/bar /:/bar $root_offset
> +ancestor /foo/bar /foo $((4+$root_offset))
> +ancestor /foo/bar /foo:/bar $((4+$root_offset))
>   ancestor /foo/bar /bar -1
>   
>   test_expect_success 'strip_path_suffix' '
>