Our color tests of "git add -p" do something a bit different from how a normal user would behave: we pretend there's a pager in use, so that Git thinks it's OK to write color to a non-tty stdout. This comes from 8539b46534 (t3701: avoid depending on the TTY prerequisite, 2019-12-06), which allows us to avoid a lot of complicated mock-tty code. However, those environment variables also make their way down to sub-processes of add--interactive, including the "diff-files" we run to generate the patches. As a result, it thinks it should output color, too. So in t3701.50, for example, the machine-readable version of the diff we get unexpectedly has color in it. We fail to parse it as a diff and think there are zero hunks. The test does still pass, though, because even with zero hunks we'll dump the diff header (and we consider those unparseable bits to be part of the header!), and so the output still has the expected color codes in it. We don't notice that the command was totally broken and failed to apply anything. And in fact we're not really testing what we think we are about the color, either. While add--interactive does correctly show the version we got from running "diff-files --color", we'd also pass the test if we had accidentally shown the machine-readable version, too, since it (erroneously) has color codes in it. One could argue that the test isn't very realistic; it's setting up this "pretend there's a pager" situation to get around the tty restrictions of the test environment. So one option would be to move back towards using a real tty. But the behavior of add--interactive really is user-visible here. If a user, for whatever reason, did run "git --paginate add --patch" (perhaps because their pager is really a filter or something), the command would totally fail to do anything useful. Since we know that we don't want color in this output, let's just make add--interactive more defensive, and say "--no-color" explicitly. It doesn't hurt anything in the common case, but it fixes this odd case and lets our test function properly again. Note that the C builtin run_add_p() already passes --no-color, so it doesn't need a similar fix. That will eventually replace this perl code anyway, but the test change here will be valuable for ensuring that. Signed-off-by: Jeff King <peff@xxxxxxxx> --- Curiously, run_add_p() claims that --no-color is important to override "diff.color = always", but in a quick test that doesn't seem to make any difference. I didn't dig into whether it's possible to trigger or not (either way, defensively using --no-color is a reasonable precaution). git-add--interactive.perl | 2 +- t/t3701-add-interactive.sh | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/git-add--interactive.perl b/git-add--interactive.perl index f36c0078ac..b6cdcfef61 100755 --- a/git-add--interactive.perl +++ b/git-add--interactive.perl @@ -714,7 +714,7 @@ sub parse_diff { if (defined $patch_mode_revision) { push @diff_cmd, get_diff_reference($patch_mode_revision); } - my @diff = run_cmd_pipe("git", @diff_cmd, "--", $path); + my @diff = run_cmd_pipe("git", @diff_cmd, qw(--no-color --), $path); my @colored = (); if ($diff_use_color) { my @display_cmd = ("git", @diff_cmd, qw(--color --), $path); diff --git a/t/t3701-add-interactive.sh b/t/t3701-add-interactive.sh index 67d1c36cef..1590cf6b98 100755 --- a/t/t3701-add-interactive.sh +++ b/t/t3701-add-interactive.sh @@ -582,6 +582,7 @@ test_expect_success 'diffs can be colorized' ' echo content >test && printf y >y && force_color git add -p >output 2>&1 <y && + git diff-files --exit-code && # 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. -- 2.28.0.889.g64d3ad7607