Merge branch 'js/add-i-a-bit-more-tests'

Test coverage update in preparation for further work on "git add -i".

* js/add-i-a-bit-more-tests:
  apply --allow-overlap: fix a corner case
  git add -p: use non-zero exit code when the diff generation failed
  t3701: verify that the diff.algorithm config setting is handled
  t3701: verify the shown messages when nothing can be added
  t3701: add a test for the different `add -p` prompts
  t3701: avoid depending on the TTY prerequisite
  t3701: add a test for advanced split-hunk editing

3 files changed, 97 insertions, 11 deletions

diff --git a/apply.c b/apply.c
index b5485ef6c9..fab44322c5 100644
--- a/apply.c
+++ b/apply.c
@@ -2662,6 +2662,16 @@ static int find_pos(struct apply_state *state,
 	int backwards_lno, forwards_lno, current_lno;
 
 	/*
+	 * When running with --allow-overlap, it is possible that a hunk is
+	 * seen that pretends to start at the beginning (but no longer does),
+	 * and that *still* needs to match the end. So trust `match_end` more
+	 * than `match_beginning`.
+	 */
+	if (state->allow_overlap && match_beginning && match_end &&
+	    img->nr - preimage->nr != 0)
+		match_beginning = 0;
+
+	/*
 	 * If match_beginning or match_end is specified, there is no
 	 * point starting from a wrong line that will never match and
 	 * wander around and wait for a match at the specified end.
diff --git a/git-add--interactive.perl b/git-add--interactive.perl
index 52659bb74c..10fd30ae16 100755
--- a/git-add--interactive.perl
+++ b/git-add--interactive.perl
@@ -177,7 +177,9 @@ sub run_cmd_pipe {
 	} else {
 		my $fh = undef;
 		open($fh, '-|', @_) or die;
-		return <$fh>;
+		my @out = <$fh>;
+		close $fh || die "Cannot close @_ ($!)";
+		return @out;
 	}
 }
 
@@ -224,7 +226,7 @@ my $status_head = sprintf($status_fmt, __('staged'), __('unstaged'), __('path'))
 	sub get_empty_tree {
 		return $empty_tree if defined $empty_tree;
 
-		$empty_tree = run_cmd_pipe(qw(git hash-object -t tree /dev/null));
+		($empty_tree) = run_cmd_pipe(qw(git hash-object -t tree /dev/null));
 		chomp $empty_tree;
 		return $empty_tree;
 	}
@@ -1127,7 +1129,7 @@ aborted and the hunk is left unchanged.
 EOF2
 	close $fh;
 
-	chomp(my $editor = run_cmd_pipe(qw(git var GIT_EDITOR)));
+	chomp(my ($editor) = run_cmd_pipe(qw(git var GIT_EDITOR)));
 	system('sh', '-c', $editor.' "$@"', $editor, $hunkfile);
 
 	if ($? != 0) {
diff --git a/t/t3701-add-interactive.sh b/t/t3701-add-interactive.sh
index d4f9386621..5db6432e33 100755
--- a/t/t3701-add-interactive.sh
+++ b/t/t3701-add-interactive.sh
@@ -23,6 +23,17 @@ diff_cmp () {
 	test_cmp "$1.filtered" "$2.filtered"
 }
 
+# This function uses a trick to manipulate the interactive add to use color:
+# the `want_color()` function special-cases the situation where a pager was
+# spawned and Git now wants to output colored text: to detect that situation,
+# the environment variable `GIT_PAGER_IN_USE` is set. However, color is
+# suppressed despite that environment variable if the `TERM` variable
+# indicates a dumb terminal, so we set that variable, too.
+
+force_color () {
+	env GIT_PAGER_IN_USE=true TERM=vt100 "$@"
+}
+
 test_expect_success 'setup (initial)' '
 	echo content >file &&
 	git add file &&
@@ -94,7 +105,6 @@ test_expect_success 'revert works (commit)' '
 	grep "unchanged *+3/-0 file" output
 '
 
-
 test_expect_success 'setup expected' '
 	cat >expected <<-\EOF
 	EOF
@@ -263,6 +273,35 @@ test_expect_success FILEMODE 'stage mode and hunk' '
 
 # end of tests disabled when filemode is not usable
 
+test_expect_success 'different prompts for mode change/deleted' '
+	git reset --hard &&
+	>file &&
+	>deleted &&
+	git add --chmod=+x file deleted &&
+	echo changed >file &&
+	rm deleted &&
+	test_write_lines n n n |
+	git -c core.filemode=true add -p >actual &&
+	sed -n "s/^\(([0-9/]*) Stage .*?\).*/\1/p" actual >actual.filtered &&
+	cat >expect <<-\EOF &&
+	(1/1) Stage deletion [y,n,q,a,d,?]?
+	(1/2) Stage mode change [y,n,q,a,d,j,J,g,/,?]?
+	(2/2) Stage this hunk [y,n,q,a,d,K,g,/,e,?]?
+	EOF
+	test_cmp expect actual.filtered
+'
+
+test_expect_success 'correct message when there is nothing to do' '
+	git reset --hard &&
+	git add -p 2>err &&
+	test_i18ngrep "No changes" err &&
+	printf "\\0123" >binary &&
+	git add binary &&
+	printf "\\0abc" >binary &&
+	git add -p 2>err &&
+	test_i18ngrep "Only binary files changed" err
+'
+
 test_expect_success 'setup again' '
 	git reset --hard &&
 	test_chmod +x file &&
@@ -403,6 +442,28 @@ test_expect_failure 'split hunk "add -p (no, yes, edit)"' '
 	! grep "^+31" actual
 '
 
+test_expect_failure 'edit, adding lines to the first hunk' '
+	test_write_lines 10 11 20 30 40 50 51 60 >test &&
+	git reset &&
+	tr _ " " >patch <<-EOF &&
+	@@ -1,5 +1,6 @@
+	_10
+	+11
+	+12
+	_20
+	+21
+	+22
+	_30
+	EOF
+	# test sequence is s(plit), e(dit), n(o)
+	# q n q q is there to make sure we exit at the end.
+	printf "%s\n" s e n   q n q q |
+	EDITOR=./fake_editor.sh git add -p 2>error &&
+	test_must_be_empty error &&
+	git diff --cached >actual &&
+	grep "^+22" actual
+'
+
 test_expect_success 'patch mode ignores unmerged entries' '
 	git reset --hard &&
 	test_commit conflict &&
@@ -429,35 +490,48 @@ test_expect_success 'patch mode ignores unmerged entries' '
 	diff_cmp expected diff
 '
 
-test_expect_success TTY 'diffs can be colorized' '
+test_expect_success 'diffs can be colorized' '
 	git reset --hard &&
 
 	echo content >test &&
-	printf y | test_terminal git add -p >output 2>&1 &&
+	printf y >y &&
+	force_color git add -p >output 2>&1 <y &&
 
 	# We do not want to depend on the exact coloring scheme
 	# git uses for diffs, so just check that we saw some kind of color.
 	grep "$(printf "\\033")" output
 '
 
-test_expect_success TTY 'diffFilter filters diff' '
+test_expect_success 'diffFilter filters diff' '
 	git reset --hard &&
 
 	echo content >test &&
 	test_config interactive.diffFilter "sed s/^/foo:/" &&
-	printf y | test_terminal git add -p >output 2>&1 &&
+	printf y >y &&
+	force_color git add -p >output 2>&1 <y &&
 
 	# avoid depending on the exact coloring or content of the prompts,
 	# and just make sure we saw our diff prefixed
 	grep foo:.*content output
 '
 
-test_expect_success TTY 'detect bogus diffFilter output' '
+test_expect_success 'detect bogus diffFilter output' '
 	git reset --hard &&
 
 	echo content >test &&
 	test_config interactive.diffFilter "echo too-short" &&
-	printf y | test_must_fail test_terminal git add -p
+	printf y >y &&
+	test_must_fail force_color git add -p <y
+'
+
+test_expect_success 'diff.algorithm is passed to `git diff-files`' '
+	git reset --hard &&
+
+	>file &&
+	git add file &&
+	echo changed >file &&
+	test_must_fail git -c diff.algorithm=bogus add -p 2>err &&
+	test_i18ngrep "error: option diff-algorithm accepts " err
 '
 
 test_expect_success 'patch-mode via -i prompts for files' '
@@ -667,7 +741,7 @@ test_expect_success 'show help from add--helper' '
 	<BOLD;BLUE>What now<RESET>>$SP
 	Bye.
 	EOF
-	test_write_lines h | GIT_PAGER_IN_USE=true TERM=vt100 git add -i >actual.colored &&
+	test_write_lines h | force_color git add -i >actual.colored &&
 	test_decode_color <actual.colored >actual &&
 	test_i18ncmp expect actual
 '