Sometimes people want to specify additional configuration data
as "best effort" basis. Maybe commit.template configuration file points
at somewhere in ~/template/ but on a particular system, the file may not
exist and the user may be OK without using the template in such a case.
When the value given to a configuration variable whose type is
pathname wants to signal such an optional file, it can be marked by
prepending ":(optional)" in front of it. Such a setting that is
marked optional would avoid getting the command barf for a missing
file, as an optional configuration setting that names a missing or
an empty file is not even seen.
cf. <xmqq5ywehb69.fsf@gitster.g>
Signed-off-by: Junio C Hamano <gitster@xxxxxxxxx>
---
Documentation/config.txt | 5 ++++-
config.c | 16 ++++++++++++++--
t/t7500-commit-template-squash-signoff.sh | 9 +++++++++
3 files changed, 27 insertions(+), 3 deletions(-)
diff --git a/Documentation/config.txt b/Documentation/config.txt
index 8c0b3ed807..199e29ccea 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -358,7 +358,10 @@ compiled without runtime prefix support, the compiled-in prefix will be
substituted instead. In the unlikely event that a literal path needs to
be specified that should _not_ be expanded, it needs to be prefixed by
`./`, like so: `./%(prefix)/bin`.
-
++
+If prefixed with `:(optional)`, the configuration variable is treated
+as if it does not exist, if the named path does not exist or names an
+empty file.
Variables
~~~~~~~~~
diff --git a/config.c b/config.c
index a11bb85da3..4a060f1d82 100644
--- a/config.c
+++ b/config.c
@@ -1364,11 +1364,23 @@ int git_config_string(char **dest, const char *var, const char *value)
int git_config_pathname(char **dest, const char *var, const char *value)
{
+ int is_optional;
+ char *path;
+
if (!value)
return config_error_nonbool(var);
- *dest = interpolate_path(value, 0);
- if (!*dest)
+
+ is_optional = skip_prefix(value, ":(optional)", &value);
+ path = interpolate_path(value, 0);
+ if (!path)
die(_("failed to expand user dir in: '%s'"), value);
+
+ if (is_optional && is_empty_or_missing_file(path)) {
+ free(path);
+ return 0;
+ }
+
+ *dest = path;
return 0;
}
diff --git a/t/t7500-commit-template-squash-signoff.sh b/t/t7500-commit-template-squash-signoff.sh
index 4927b7260d..e28a79987d 100755
--- a/t/t7500-commit-template-squash-signoff.sh
+++ b/t/t7500-commit-template-squash-signoff.sh
@@ -46,6 +46,15 @@ test_expect_success 'nonexistent template file in config should return error' '
)
'
+test_expect_success 'nonexistent optional template file in config' '
+ test_config commit.template ":(optional)$PWD"/notexist &&
+ (
+ GIT_EDITOR="echo hello >\"\$1\"" &&
+ export GIT_EDITOR &&
+ git commit --allow-empty
+ )
+'
+
# From now on we'll use a template file that exists.
TEMPLATE="$PWD"/template
--
2.47.0-148-g19c85929c5
