config: learn the "onbranch:" includeIf condition

Currently, if a user wishes to have individual settings per branch, they
are required to manually keep track of the settings in their head and
manually set the options on the command-line or change the config at
each branch.

Teach config the "onbranch:" includeIf condition so that it can
conditionally include configuration files if the branch that is checked
out in the current worktree matches the pattern given.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 7e2a6f61f593921450c311b05269a3555baa97ad..e3f5bc3396d0c7502f16eed989220c8e2010bcc1 100644 (file)
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -144,6 +144,20 @@ refer to linkgit:gitignore[5] for details. For convenience:
        This is the same as `gitdir` except that matching is done
        case-insensitively (e.g. on case-insensitive file sytems)
 
+`onbranch`::
+       The data that follows the keyword `onbranch:` is taken to be a
+       pattern with standard globbing wildcards and two additional
+       ones, `**/` and `/**`, that can match multiple path components.
+       If we are in a worktree where the name of the branch that is
+       currently checked out matches the pattern, the include condition
+       is met.
++
+If the pattern ends with `/`, `**` will be automatically added. For
+example, the pattern `foo/` becomes `foo/**`. In other words, it matches
+all branches that begin with `foo/`. This is useful if your branches are
+organized hierarchically and you would like to apply a configuration to
+all the branches in that hierarchy.
+
 A few more notes on matching via `gitdir` and `gitdir/i`:
 
  * Symlinks in `$GIT_DIR` are not resolved before matching.
@@ -206,6 +220,11 @@ Example
        [includeIf "gitdir:/path/to/group/"]
                path = foo.inc
 
+       ; include only if we are in a worktree where foo-branch is
+       ; currently checked out
+       [includeIf "onbranch:foo-branch"]
+               path = foo.inc
+
 Values
 ~~~~~~
 

diff --git a/config.c b/config.c
index 296a6d9cc4110bd7fcef542ac9cc9cfe04d4f4d4..ad4166e24312b869f1add698b100d3991e42859d 100644 (file)
--- a/config.c
+++ b/config.c
@@ -19,6 +19,7 @@
 #include "utf8.h"
 #include "dir.h"
 #include "color.h"
+#include "refs.h"
 
 struct config_source {
        struct config_source *prev;
@@ -170,6 +171,12 @@ static int handle_path_include(const char *path, struct config_include_data *inc
        return ret;
 }
 
+static void add_trailing_starstar_for_dir(struct strbuf *pat)
+{
+       if (pat->len && is_dir_sep(pat->buf[pat->len - 1]))
+               strbuf_addstr(pat, "**");
+}
+
 static int prepare_include_condition_pattern(struct strbuf *pat)
 {
        struct strbuf path = STRBUF_INIT;
@@ -199,8 +206,7 @@ static int prepare_include_condition_pattern(struct strbuf *pat)
        } else if (!is_absolute_path(pat->buf))
                strbuf_insert(pat, 0, "**/", 3);
 
-       if (pat->len && is_dir_sep(pat->buf[pat->len - 1]))
-               strbuf_addstr(pat, "**");
+       add_trailing_starstar_for_dir(pat);
 
        strbuf_release(&path);
        return prefix;
@@ -264,6 +270,25 @@ static int include_by_gitdir(const struct config_options *opts,
        return ret;
 }
 
+static int include_by_branch(const char *cond, size_t cond_len)
+{
+       int flags;
+       int ret;
+       struct strbuf pattern = STRBUF_INIT;
+       const char *refname = resolve_ref_unsafe("HEAD", 0, NULL, &flags);
+       const char *shortname;
+
+       if (!refname || !(flags & REF_ISSYMREF) ||
+                       !skip_prefix(refname, "refs/heads/", &shortname))
+               return 0;
+
+       strbuf_add(&pattern, cond, cond_len);
+       add_trailing_starstar_for_dir(&pattern);
+       ret = !wildmatch(pattern.buf, shortname, WM_PATHNAME);
+       strbuf_release(&pattern);
+       return ret;
+}
+
 static int include_condition_is_true(const struct config_options *opts,
                                     const char *cond, size_t cond_len)
 {
@@ -272,6 +297,8 @@ static int include_condition_is_true(const struct config_options *opts,
                return include_by_gitdir(opts, cond, cond_len, 0);
        else if (skip_prefix_mem(cond, cond_len, "gitdir/i:", &cond, &cond_len))
                return include_by_gitdir(opts, cond, cond_len, 1);
+       else if (skip_prefix_mem(cond, cond_len, "onbranch:", &cond, &cond_len))
+               return include_by_branch(cond, cond_len);
 
        /* unknown conditionals are always false */
        return 0;

diff --git a/t/t1305-config-include.sh b/t/t1305-config-include.sh
index 579a86b7f8f6f876434bc1107e051304bc45afc6..9571e366f801ea347845eef9736c92197fbdba08 100755 (executable)
--- a/t/t1305-config-include.sh
+++ b/t/t1305-config-include.sh
@@ -309,6 +309,45 @@ test_expect_success SYMLINKS 'conditional include, gitdir matching symlink, icas
        )
 '
 
+test_expect_success 'conditional include, onbranch' '
+       echo "[includeIf \"onbranch:foo-branch\"]path=bar9" >>.git/config &&
+       echo "[test]nine=9" >.git/bar9 &&
+       git checkout -b master &&
+       test_must_fail git config test.nine &&
+       git checkout -b foo-branch &&
+       echo 9 >expect &&
+       git config test.nine >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'conditional include, onbranch, wildcard' '
+       echo "[includeIf \"onbranch:?oo-*/**\"]path=bar10" >>.git/config &&
+       echo "[test]ten=10" >.git/bar10 &&
+       git checkout -b not-foo-branch/a &&
+       test_must_fail git config test.ten &&
+
+       echo 10 >expect &&
+       git checkout -b foo-branch/a/b/c &&
+       git config test.ten >actual &&
+       test_cmp expect actual &&
+
+       git checkout -b moo-bar/a &&
+       git config test.ten >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'conditional include, onbranch, implicit /** for /' '
+       echo "[includeIf \"onbranch:foo-dir/\"]path=bar11" >>.git/config &&
+       echo "[test]eleven=11" >.git/bar11 &&
+       git checkout -b not-foo-dir/a &&
+       test_must_fail git config test.eleven &&
+
+       echo 11 >expect &&
+       git checkout -b foo-dir/a/b/c &&
+       git config test.eleven >actual &&
+       test_cmp expect actual
+'
+
 test_expect_success 'include cycles are detected' '
        cat >.gitconfig <<-\EOF &&
        [test]value = gitconfig