Re: [PATCH v2] log: add log.excludeDecoration config option

> From: Derrick Stolee <dstolee@microsoft.com>
>
> In 'git log', the --decorate-refs-exclude option appends a pattern
> to a string_list. This list is used to prevent showing some refs
> in the decoration output, or even by --simplify-by-decoration.
>
> Users may want to use their refs space to store utility refs that
> should not appear in the decoration output. For example, Scalar [1]
> runs a background fetch but places the "new" refs inside the
> refs/scalar/hidden/<remote>/* refspace instead of refs/<remote>/*
> to avoid updating remote refs when the user is not looking. However,
> these "hidden" refs appear during regular 'git log' queries.
>
> A similar idea to use "hidden" refs is under consideration for core
> Git [2].
>
> Add the 'log.excludeDecoration' config option so users can exclude
> some refs from decorations by default instead of needing to use
> --decorate-refs-exclude manually. The config value is multi-valued
> much like the command-line option. The documentation is careful to
> point out that the config value can be overridden by the
> --decorate-refs option, even though --decorate-refs-exclude would
> always "win" over --decorate-refs.
>
> Since the 'log.excludeDecoration' takes lower precedence to
> --decorate-refs, and --decorate-refs-exclude takes higher
> precedence, the struct decoration_filter needed another field.
> This led also to new logic in load_ref_decorations() and
> ref_filter_match().
>
> There are several tests in t4202-log.sh that test the
> --decorate-refs-(include|exclude) options, so these are extended.
> Since the expected output is already stored as a file, most tests
> could simply replace a "--decorate-refs-exclude" option with an
> in-line config setting. Other tests involve the precedence of
> the config option compared to command-line options and needed more
> modification.
>
> [1] https://github.com/microsoft/scalar
> [2] https://lore.kernel.org/git/77b1da5d3063a2404cd750adfe3bb8be9b6c497d.1585946894.git.gitgitgadget@gmail.com/
>
> Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
> ---
>     log: add log.excludeDecoration config option
>
>     This was something hinted at in the "fetch" step of the background
>     maintenance RFC. Should be a relatively minor addition to our config
>     options.
>
>     We definitely want this feature for microsoft/git (we would set
>     log.excludeDecoration=refs/scalar/* in all Scalar repos), but we will
>     wait for feedback from the community.
>
>     Updates in v2:
>
>      * Use for_each_string_list_item()
>
>
>      * Update the matching logic to allow --decorate-refs to override the
>        config option.
>
>
>
>     Thanks, -Stolee

> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-610%2Fderrickstolee%2Flog-exclude-decoration-v2
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-610/derrickstolee/log-exclude-decoration-v2
> Pull-Request: https://github.com/gitgitgadget/git/pull/610
>
> [ snip range-diff ... ]
>
>  Documentation/config/log.txt |  5 ++++
>  Documentation/git-log.txt    |  5 +++-
>  builtin/log.c                | 16 ++++++++++-
>  log-tree.c                   |  6 ++++-
>  log-tree.h                   |  4 ++-
>  refs.c                       | 15 +++++++++--
>  refs.h                       | 15 ++++++++---
>  t/t4202-log.sh               | 51 +++++++++++++++++++++++++++++++++++-
>  8 files changed, 106 insertions(+), 11 deletions(-)
>
> diff --git a/Documentation/config/log.txt b/Documentation/config/log.txt
> index e9e1e397f3f..1a158324f79 100644
> --- a/Documentation/config/log.txt
> +++ b/Documentation/config/log.txt
> @@ -18,6 +18,11 @@ log.decorate::
>  	names are shown. This is the same as the `--decorate` option
>  	of the `git log`.
>
> +log.excludeDecoration::
> +	Exclude the specified patterns from the log decorations. This multi-
> +	valued config option is the same as the `--decorate-refs-exclude`
> +	option of `git log`.
> +

>  log.follow::
>  	If `true`, `git log` will act as if the `--follow` option was used when
>  	a single <path> is given.  This has the same limitations as `--follow`,
> diff --git a/Documentation/git-log.txt b/Documentation/git-log.txt
> index bed09bb09e5..17592234ba4 100644
> --- a/Documentation/git-log.txt
> +++ b/Documentation/git-log.txt
> @@ -43,7 +43,10 @@ OPTIONS
>  	If no `--decorate-refs` is given, pretend as if all refs were
>  	included.  For each candidate, do not use it for decoration if it
>  	matches any patterns given to `--decorate-refs-exclude` or if it
> -	doesn't match any of the patterns given to `--decorate-refs`.
> +	doesn't match any of the patterns given to `--decorate-refs`. The
> +	`log.excludeDecoration` config option allows excluding refs from
> +	the decorations, but an explicit `--decorate-refs` pattern will
> +	override a match in `log.excludeDecoration`.
>
>  --source::
>  	Print out the ref name given on the command line by which each
> diff --git a/builtin/log.c b/builtin/log.c
> index 83a4a6188e2..72192710dcd 100644
> --- a/builtin/log.c
> +++ b/builtin/log.c
> @@ -164,9 +164,11 @@ static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
>  	int quiet = 0, source = 0, mailmap;
>  	static struct line_opt_callback_data line_cb = {NULL, NULL, STRING_LIST_INIT_DUP};
>  	static struct string_list decorate_refs_exclude = STRING_LIST_INIT_NODUP;
> +	static struct string_list decorate_refs_exclude_config = STRING_LIST_INIT_NODUP;
>  	static struct string_list decorate_refs_include = STRING_LIST_INIT_NODUP;
>  	struct decoration_filter decoration_filter = {&decorate_refs_include,
> -						      &decorate_refs_exclude};
> +						      &decorate_refs_exclude,
> +						      &decorate_refs_exclude_config};
>  	static struct revision_sources revision_sources;
>
>  	const struct option builtin_log_options[] = {
> @@ -236,7 +238,19 @@ static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
>  	}
>
>  	if (decoration_style) {
> +		const struct string_list *config_exclude =
> +			repo_config_get_value_multi(the_repository,
> +						    "log.excludeDecoration");
> +
> +		if (config_exclude) {
> +			struct string_list_item *item;
> +			for_each_string_list_item(item, config_exclude)
> +				string_list_append(&decorate_refs_exclude_config,
> +						   item->string);
> +		}
> +
>  		rev->show_decorations = 1;
> +
>  		load_ref_decorations(&decoration_filter, decoration_style);
>  	}
>
> diff --git a/log-tree.c b/log-tree.c
> index 52127427ffe..bd8d4c07bb8 100644
> --- a/log-tree.c
> +++ b/log-tree.c
> @@ -90,7 +90,8 @@ static int add_ref_decoration(const char *refname, const struct object_id *oid,
>
>  	if (filter && !ref_filter_match(refname,
>  			      filter->include_ref_pattern,
> -			      filter->exclude_ref_pattern))
> +			      filter->exclude_ref_pattern,
> +			      filter->exclude_ref_config_pattern))
>  		return 0;
>
>  	if (starts_with(refname, git_replace_ref_base)) {
> @@ -155,6 +156,9 @@ void load_ref_decorations(struct decoration_filter *filter, int flags)
>  			for_each_string_list_item(item, filter->include_ref_pattern) {
>  				normalize_glob_ref(item, NULL, item->string);
>  			}
> +			for_each_string_list_item(item, filter->exclude_ref_config_pattern) {
> +				normalize_glob_ref(item, NULL, item->string);
> +			}
>  		}
>  		decoration_loaded = 1;
>  		decoration_flags = flags;
> diff --git a/log-tree.h b/log-tree.h
> index e6686280746..8fa79289ec6 100644
> --- a/log-tree.h
> +++ b/log-tree.h
> @@ -8,7 +8,9 @@ struct log_info {
>  };
>
>  struct decoration_filter {
> -	struct string_list *include_ref_pattern, *exclude_ref_pattern;
> +	struct string_list *include_ref_pattern;
> +	struct string_list *exclude_ref_pattern;
> +	struct string_list *exclude_ref_config_pattern;
>  };
>
>  int parse_decorate_color_config(const char *var, const char *slot_name, const char *value);
> diff --git a/refs.c b/refs.c
> index 1ab0bb54d3d..63d8b569333 100644
> --- a/refs.c
> +++ b/refs.c
> @@ -339,9 +339,11 @@ static int match_ref_pattern(const char *refname,
>
>  int ref_filter_match(const char *refname,
>  		     const struct string_list *include_patterns,
> -		     const struct string_list *exclude_patterns)
> +		     const struct string_list *exclude_patterns,
> +		     const struct string_list *exclude_patterns_config)
>  {
>  	struct string_list_item *item;
> +	int found = 0;
>
>  	if (exclude_patterns && exclude_patterns->nr) {
>  		for_each_string_list_item(item, exclude_patterns) {
> @@ -351,7 +353,6 @@ int ref_filter_match(const char *refname,
>  	}
>
>  	if (include_patterns && include_patterns->nr) {
> -		int found = 0;
>  		for_each_string_list_item(item, include_patterns) {
>  			if (match_ref_pattern(refname, item)) {
>  				found = 1;
> @@ -362,6 +363,16 @@ int ref_filter_match(const char *refname,
>  		if (!found)
>  			return 0;
>  	}
> +
> +	if (!found &&
> +	    exclude_patterns_config &&
> +	    exclude_patterns_config->nr) {
> +		for_each_string_list_item(item, exclude_patterns_config) {
> +			if (match_ref_pattern(refname, item))
> +				return 0;
> +		}
> +	}
> +
>  	return 1;
>  }
>
> diff --git a/refs.h b/refs.h
> index 545029c6d80..7cec33303d7 100644
> --- a/refs.h
> +++ b/refs.h
> @@ -362,16 +362,23 @@ void normalize_glob_ref(struct string_list_item *item, const char *prefix,
>  			const char *pattern);
>
>  /*
> - * Returns 0 if refname matches any of the exclude_patterns, or if it doesn't
> - * match any of the include_patterns. Returns 1 otherwise.
> + * Returns 0 if the refname matches any of the exclude_patterns.
> + *
> + * Returns 0 if include_patterns is non-empty but refname does not match
> + * any of those patterns.
> + *
> + * Returns 0 if refname matches a pattern in exclude_patterns_config but
> + * does not match any pattern in inclue_patterns.
> + *
> + * Otherwise, returns 1.
>   *
> - * If pattern list is NULL or empty, matching against that list is skipped.
>   * This has the effect of matching everything by default, unless the user
>   * specifies rules otherwise.
>   */
>  int ref_filter_match(const char *refname,
>  		     const struct string_list *include_patterns,
> -		     const struct string_list *exclude_patterns);
> +		     const struct string_list *exclude_patterns,
> +		     const struct string_list *exclude_patterns_config);
>
>  static inline const char *has_glob_specials(const char *pattern)
>  {
> diff --git a/t/t4202-log.sh b/t/t4202-log.sh
> index 0f766ba65f5..78f9ade6870 100755
> --- a/t/t4202-log.sh
> +++ b/t/t4202-log.sh
> @@ -742,7 +742,23 @@ test_expect_success 'decorate-refs with glob' '
>  	octopus-a (octopus-a)
>  	reach
>  	EOF
> +	cat >expect.no-decorate <<-\EOF &&
> +	Merge-tag-reach
> +	Merge-tags-octopus-a-and-octopus-b
> +	seventh
> +	octopus-b
> +	octopus-a
> +	reach
> +	EOF
> +	git log -n6 --decorate=short --pretty="tformat:%f%d" \
> +		--decorate-refs="heads/octopus*" >actual &&
> +	test_cmp expect.decorate actual &&
>  	git log -n6 --decorate=short --pretty="tformat:%f%d" \
> +		--decorate-refs-exclude="heads/octopus*" \
> +		--decorate-refs="heads/octopus*" >actual &&
> +	test_cmp expect.no-decorate actual &&
> +	git -c log.excludeDecoration="heads/octopus*" log \
> +		-n6 --decorate=short --pretty="tformat:%f%d" \
>  		--decorate-refs="heads/octopus*" >actual &&
>  	test_cmp expect.decorate actual
>  '
> @@ -787,6 +803,9 @@ test_expect_success 'decorate-refs-exclude with glob' '
>  	EOF
>  	git log -n6 --decorate=short --pretty="tformat:%f%d" \
>  		--decorate-refs-exclude="heads/octopus*" >actual &&
> +	test_cmp expect.decorate actual &&
> +	git -c log.excludeDecoration="heads/octopus*" log \
> +		-n6 --decorate=short --pretty="tformat:%f%d" >actual &&
>  	test_cmp expect.decorate actual
>  '
>
> @@ -801,6 +820,9 @@ test_expect_success 'decorate-refs-exclude without globs' '
>  	EOF
>  	git log -n6 --decorate=short --pretty="tformat:%f%d" \
>  		--decorate-refs-exclude="tags/reach" >actual &&
> +	test_cmp expect.decorate actual &&
> +	git -c log.excludeDecoration="tags/reach" log \
> +		-n6 --decorate=short --pretty="tformat:%f%d" >actual &&
>  	test_cmp expect.decorate actual
>  '
>
> @@ -816,11 +838,19 @@ test_expect_success 'multiple decorate-refs-exclude' '
>  	git log -n6 --decorate=short --pretty="tformat:%f%d" \
>  		--decorate-refs-exclude="heads/octopus*" \
>  		--decorate-refs-exclude="tags/reach" >actual &&
> +	test_cmp expect.decorate actual &&
> +	git -c log.excludeDecoration="heads/octopus*" \
> +		-c log.excludeDecoration="tags/reach" log \
> +		-n6 --decorate=short --pretty="tformat:%f%d" >actual &&
> +	test_cmp expect.decorate actual &&
> +	git -c log.excludeDecoration="heads/octopus*" log \
> +		--decorate-refs-exclude="tags/reach" \
> +		-n6 --decorate=short --pretty="tformat:%f%d" >actual &&
>  	test_cmp expect.decorate actual
>  '
>
>  test_expect_success 'decorate-refs and decorate-refs-exclude' '
> -	cat >expect.decorate <<-\EOF &&
> +	cat >expect.no-decorate <<-\EOF &&
>  	Merge-tag-reach (master)
>  	Merge-tags-octopus-a-and-octopus-b
>  	seventh
> @@ -831,6 +861,21 @@ test_expect_success 'decorate-refs and decorate-refs-exclude' '
>  	git log -n6 --decorate=short --pretty="tformat:%f%d" \
>  		--decorate-refs="heads/*" \
>  		--decorate-refs-exclude="heads/oc*" >actual &&
> +	test_cmp expect.no-decorate actual
> +'
> +
> +test_expect_success 'deocrate-refs and log.excludeDecoration' '
> +	cat >expect.decorate <<-\EOF &&
> +	Merge-tag-reach (master)
> +	Merge-tags-octopus-a-and-octopus-b
> +	seventh
> +	octopus-b (octopus-b)
> +	octopus-a (octopus-a)
> +	reach (reach)
> +	EOF
> +	git -c log.excludeDecoration="heads/oc*" log \
> +		--decorate-refs="heads/*" \
> +		-n6 --decorate=short --pretty="tformat:%f%d" >actual &&
>  	test_cmp expect.decorate actual
>  '
>
> @@ -846,6 +891,10 @@ test_expect_success 'decorate-refs-exclude and simplify-by-decoration' '
>  	git log -n6 --decorate=short --pretty="tformat:%f%d" \
>  		--decorate-refs-exclude="*octopus*" \
>  		--simplify-by-decoration >actual &&
> +	test_cmp expect.decorate actual &&
> +	git -c log.excludeDecoration="*octopus*" log \
> +		-n6 --decorate=short --pretty="tformat:%f%d" \
> +		--simplify-by-decoration >actual &&
>  	test_cmp expect.decorate actual
>  '
>
>
> base-commit: 274b9cc25322d9ee79aa8e6d4e86f0ffe5ced925
> --