[PATCH] t7800-difftool: don't accidentally match tmp dirs

["SZEDER Gábor" <szeder.dev@gmail.com>]

In a bunch of test cases in 't7800-difftool.sh' we 'grep' for specific
filenames in 'git difftool's output, and those test cases are prone to
occasional failures because those filenames might be part of the name
of difftool's temporary directory as well, e.g.:

  +git difftool --dir-diff --no-symlinks --extcmd ls v1
  +grep sub output
  +test_line_count = 2 sub-output
  test_line_count: line count for sub-output != 2
  /tmp/git-difftool.Ssubfq/left/:
  sub
  /tmp/git-difftool.Ssubfq/right/:
  sub
  error: last command exited with $?=1
  not ok 50 - difftool --dir-diff v1 from subdirectory --no-symlinks

Fix this by tightening those test cases: filter out difftool's
temporary directories from its output, and use here docs to list and
test_cmp to check all files expected to present in those directories
explicitly.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
---
 t/t7800-difftool.sh | 112 ++++++++++++++++++++++++++++++--------------
 1 file changed, 78 insertions(+), 34 deletions(-)

diff --git a/t/t7800-difftool.sh b/t/t7800-difftool.sh
index a578b35761..fe02fe1688 100755
--- a/t/t7800-difftool.sh
+++ b/t/t7800-difftool.sh
@@ -439,73 +439,104 @@ run_dir_diff_test () {
 }
 
 run_dir_diff_test 'difftool -d' '
+	cat >expect <<-\EOF &&
+	file
+	file2
+
+	file
+	file2
+	sub
+	EOF
 	git difftool -d $symlinks --extcmd ls branch >output &&
-	grep sub output &&
-	grep file output
+	grep -v ^/ output >actual &&
+	test_cmp expect actual
 '
 
 run_dir_diff_test 'difftool --dir-diff' '
+	cat >expect <<-\EOF &&
+	file
+	file2
+
+	file
+	file2
+	sub
+	EOF
 	git difftool --dir-diff $symlinks --extcmd ls branch >output &&
-	grep sub output &&
-	grep file output
+	grep -v ^/ output >actual &&
+	test_cmp expect actual
 '
 
 run_dir_diff_test 'difftool --dir-diff ignores --prompt' '
+	cat >expect <<-\EOF &&
+	file
+	file2
+
+	file
+	file2
+	sub
+	EOF
 	git difftool --dir-diff $symlinks --prompt --extcmd ls branch >output &&
-	grep sub output &&
-	grep file output
+	grep -v ^/ output >actual &&
+	test_cmp expect actual
 '
 
 run_dir_diff_test 'difftool --dir-diff branch from subdirectory' '
 	(
 		cd sub &&
+		cat >expect <<-\EOF &&
+		file
+		file2
+
+		file
+		file2
+		sub
+		EOF
 		git difftool --dir-diff $symlinks --extcmd ls branch >output &&
-		# "sub" must only exist in "right"
-		# "file" and "file2" must be listed in both "left" and "right"
-		grep sub output >sub-output &&
-		test_line_count = 1 sub-output &&
-		grep file"$" output >file-output &&
-		test_line_count = 2 file-output &&
-		grep file2 output >file2-output &&
-		test_line_count = 2 file2-output
+		grep -v ^/ output >actual &&
+		test_cmp expect actual
 	)
 '
 
 run_dir_diff_test 'difftool --dir-diff v1 from subdirectory' '
 	(
 		cd sub &&
+		cat >expect <<-\EOF &&
+		file
+		sub
+
+		file
+		sub
+		EOF
 		git difftool --dir-diff $symlinks --extcmd ls v1 >output &&
-		# "sub" and "file" exist in both v1 and HEAD.
-		# "file2" is unchanged.
-		grep sub output >sub-output &&
-		test_line_count = 2 sub-output &&
-		grep file output >file-output &&
-		test_line_count = 2 file-output &&
-		! grep file2 output
+		grep -v ^/ output >actual &&
+		test_cmp expect actual
 	)
 '
 
 run_dir_diff_test 'difftool --dir-diff branch from subdirectory w/ pathspec' '
 	(
 		cd sub &&
+		cat >expect <<-\EOF &&
+
+		sub
+		EOF
 		git difftool --dir-diff $symlinks --extcmd ls branch -- .>output &&
-		# "sub" only exists in "right"
-		# "file" and "file2" must not be listed
-		grep sub output >sub-output &&
-		test_line_count = 1 sub-output &&
-		! grep file output
+		grep -v ^/ output >actual &&
+		test_cmp expect actual
 	)
 '
 
 run_dir_diff_test 'difftool --dir-diff v1 from subdirectory w/ pathspec' '
 	(
 		cd sub &&
+		cat >expect <<-\EOF &&
+		sub
+
+		sub
+		EOF
 		git difftool --dir-diff $symlinks --extcmd ls v1 -- .>output &&
-		# "sub" exists in v1 and HEAD
-		# "file" is filtered out by the pathspec
-		grep sub output >sub-output &&
-		test_line_count = 2 sub-output &&
-		! grep file output
+		grep -v ^/ output >actual &&
+		test_cmp expect actual
 	)
 '
 
@@ -516,18 +547,31 @@ run_dir_diff_test 'difftool --dir-diff from subdirectory with GIT_DIR set' '
 		GIT_WORK_TREE=$(pwd) &&
 		export GIT_WORK_TREE &&
 		cd sub &&
+		cat >expect <<-\EOF &&
+
+		sub
+		EOF
 		git difftool --dir-diff $symlinks --extcmd ls \
 			branch -- sub >output &&
-		grep sub output &&
-		! grep file output
+		grep -v ^/ output >actual &&
+		test_cmp expect actual
 	)
 '
 
 run_dir_diff_test 'difftool --dir-diff when worktree file is missing' '
 	test_when_finished git reset --hard &&
 	rm file2 &&
+	cat >expect <<-\EOF &&
+	file
+	file2
+
+	file
+	file2
+	sub
+	EOF
 	git difftool --dir-diff $symlinks --extcmd ls branch master >output &&
-	grep file2 output
+	grep -v ^/ output >actual &&
+	test_cmp expect actual
 '
 
 run_dir_diff_test 'difftool --dir-diff with unmerged files' '
-- 
2.30.0.rc2.444.gff896a3b01