# [PATCH v2] diff: fix --relative without arguments 3 messages from 2017-12-07 to 2017-12-07. Participants: Jacob Keller, Junio C Hamano. Thread: https://gitlist.dev/t/47392 ## Jacob Keller, 2017-12-07 00:59 Subject: [PATCH v2] diff: fix --relative without arguments Message-ID: <20171207005929.24109-1-jacob.e.keller@intel.com> URL: https://gitlist.dev/e/20171207005929.24109-1-jacob.e.keller%40intel.com ``` From: Jacob Keller Recently, commit f7923a5ece00 ("diff: use skip_to_optional_val()", 2017-12-04) changed how we parsed some diff options, preferring skip_to_optional_val instead of a more complex skip_prefix() setup. Unfortunately, this breaks --relative, because of the semantics of skip_to_optional_val. If no optional_val is given, then the function puts the empty string "" into the arg. Unfortunately, relative passes in options->prefix as the location for the optional argument, and expects this value to remain unchanged if no optional value was given. This results in breaking --relative when no arguments are provided. This cascades into many failures of code flow that rely on this. Partially revert the commit, and restore --relative option parsing to the previous working code. Since no tests exist for --relative without options, add a new test which will help ensure no future regressions. Signed-off-by: Jacob Keller --- Actually perform the revert of --relative handling. diff.c | 6 +++++- t/t4045-diff-relative.sh | 5 +++++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/diff.c b/diff.c index b62e4b61b564..1919afb4f104 100644 --- a/diff.c +++ b/diff.c @@ -4581,8 +4581,12 @@ int diff_opt_parse(struct diff_options *options, options->flags.rename_empty = 1; else if (!strcmp(arg, "--no-rename-empty")) options->flags.rename_empty = 0; - else if (skip_to_optional_val(arg, "--relative", &options->prefix)) + else if (!strcmp(arg, "--relative")) options->flags.relative_name = 1; + else if (skip_prefix(arg, "--relative=", &arg)) { + options->flags.relative_name = 1; + options->prefix = arg; + } /* xdiff options */ else if (!strcmp(arg, "--minimal")) diff --git a/t/t4045-diff-relative.sh b/t/t4045-diff-relative.sh index 3950f5034d31..41e4f59b2ffb 100755 --- a/t/t4045-diff-relative.sh +++ b/t/t4045-diff-relative.sh @@ -70,4 +70,9 @@ for type in diff numstat stat raw; do check_$type dir/file2 --relative=sub done +cd subdir +for type in diff numstat stat raw; do + check_$type file2 --relative +done + test_done -- 2.15.1.477.g3ed0a2a61da8 ``` ## Junio C Hamano, 2017-12-07 15:26 Subject: Re: [PATCH v2] diff: fix --relative without arguments Message-ID: URL: https://gitlist.dev/e/xmqq4lp2ftjt.fsf%40gitster.mtv.corp.google.com In-Reply-To: <20171207005929.24109-1-jacob.e.keller@intel.com> ``` Jacob Keller writes: > From: Jacob Keller > > Recently, commit f7923a5ece00 ("diff: use skip_to_optional_val()", > 2017-12-04) changed how we parsed some diff options, preferring > skip_to_optional_val instead of a more complex skip_prefix() setup. I'd expect a moral equivalent of this squashed in when Christian rerolls the skip-to-optional-val series (with helped-by: attribution to you, probably). It does not make much sense to leave the initial breakage like this one in the history. Thanks. ``` ## Jacob Keller, 2017-12-07 19:01 Subject: Re: [PATCH v2] diff: fix --relative without arguments Message-ID: URL: https://gitlist.dev/e/CA%2BP7%2BxpAFJcvcQ9PN5ZsnQxf8GpSG2yYKSYEg5wHebyCLtvdsw%40mail.gmail.com In-Reply-To: ``` On Thu, Dec 7, 2017 at 7:26 AM, Junio C Hamano wrote: > Jacob Keller writes: > >> From: Jacob Keller >> >> Recently, commit f7923a5ece00 ("diff: use skip_to_optional_val()", >> 2017-12-04) changed how we parsed some diff options, preferring >> skip_to_optional_val instead of a more complex skip_prefix() setup. > > I'd expect a moral equivalent of this squashed in when Christian > rerolls the skip-to-optional-val series (with helped-by: attribution > to you, probably). It does not make much sense to leave the initial > breakage like this one in the history. > > Thanks. Quite correct. I'll be sending a patch with just new tests shortly. Thanks, Jake ```