[v2,01/10] refs: allow "HEAD" as decoration filter

Commit Message

Derrick Stolee July 29, 2022, 7:29 p.m. UTC

From: Derrick Stolee <[e-mail]>

The normalize_glob_ref() method was introduced in 65516f586b693 (log:
add option to choose which refs to decorate, 2017-11-21) to help with
decoration filters such as --decorate-refs=<filter> and
--decorate-refs-exclude=<filter>. The method has not been used anywhere
else.

At the moment, it is impossible to specify HEAD as a decoration filter
since normalize_glob_ref() prepends "refs/" to the filter if it isn't
already there.

Allow adding HEAD as a decoration filter by allowing the exact string
"HEAD" to not be prepended with "refs/". Add a test in t4202-log.sh that
would previously fail since the HEAD decoration would exist in the
output.

It is sufficient to only cover "HEAD" here and not include other special
refs like REBASE_HEAD. This is because HEAD is the only ref outside of
refs/* that is added to the list of decorations.

Signed-off-by: Derrick Stolee <[e-mail]>
---
 refs.c         | 4 ++--
 t/t4202-log.sh | 6 ++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

Comments

Junio C Hamano Aug. 3, 2022, 6:03 a.m. UTC | #1

"Derrick Stolee via GitGitGadget" <[e-mail]> writes:

>  	if (prefix) {
>  		strbuf_addstr(&normalized_pattern, prefix);
> -	}
> -	else if (!starts_with(pattern, "refs/"))
> +	} else if (!starts_with(pattern, "refs/") &&
> +		   strcmp(pattern, "HEAD"))

Perhaps leave a needswork comment to remind us to later consider
covering all the pseudorefs like MERGE_HEAD, CHERRY_PICK_HEAD etc.?

>  		strbuf_addstr(&normalized_pattern, "refs/");

Style:

If you plan to add more code to the bodies of this if/elseif, then
have {} around all arms.  Otherwise, let's lose the {} around the
body of "if (prefix)".

Derrick Stolee Aug. 4, 2022, 1:22 p.m. UTC | #2

On 8/3/2022 2:03 AM, Junio C Hamano wrote:
> "Derrick Stolee via GitGitGadget" <[e-mail]> writes:
> 
>>  	if (prefix) {
>>  		strbuf_addstr(&normalized_pattern, prefix);
>> -	}
>> -	else if (!starts_with(pattern, "refs/"))
>> +	} else if (!starts_with(pattern, "refs/") &&
>> +		   strcmp(pattern, "HEAD"))
> 
> Perhaps leave a needswork comment to remind us to later consider
> covering all the pseudorefs like MERGE_HEAD, CHERRY_PICK_HEAD etc.?

A comment is a good idea. We should leave it for later because it
would make a visible change from the user's perspective.

>>  		strbuf_addstr(&normalized_pattern, "refs/");
> 
> Style:
> 
> If you plan to add more code to the bodies of this if/elseif, then
> have {} around all arms.  Otherwise, let's lose the {} around the
> body of "if (prefix)".

Yes, thanks for the close eyes.

Thanks,
-Stolee

Patch

diff --git a/refs.c b/refs.c
index 90bcb271687..ec3134e4842 100644
--- a/refs.c
+++ b/refs.c
@@ -457,8 +457,8 @@  void normalize_glob_ref(struct string_list_item *item, const char *prefix,
 
 	if (prefix) {
 		strbuf_addstr(&normalized_pattern, prefix);
-	}
-	else if (!starts_with(pattern, "refs/"))
+	} else if (!starts_with(pattern, "refs/") &&
+		   strcmp(pattern, "HEAD"))
 		strbuf_addstr(&normalized_pattern, "refs/");
 	strbuf_addstr(&normalized_pattern, pattern);
 	strbuf_strip_suffix(&normalized_pattern, "/");
diff --git a/t/t4202-log.sh b/t/t4202-log.sh
index 6e663525582..6b7d8e269f7 100755
--- a/t/t4202-log.sh
+++ b/t/t4202-log.sh
@@ -1025,6 +1025,12 @@  test_expect_success 'decorate-refs and simplify-by-decoration without output' '
 	test_cmp expect actual
 '
 
+test_expect_success 'decorate-refs-exclude HEAD' '
+	git log --decorate=full --oneline \
+		--decorate-refs-exclude="HEAD" >actual &&
+	! grep HEAD actual
+'
+
 test_expect_success 'log.decorate config parsing' '
 	git log --oneline --decorate=full >expect.full &&
 	git log --oneline --decorate=short >expect.short &&