submodule--helper: add gitdir migration command

Manually running
"git config submodule.<name>.gitdir .git/modules/<name>"
for each submodule can be impractical, so add a migration command to
submodule--helper to automatically create configs for all submodules
as required by extensions.submodulePathConfig.

The command calls create_default_gitdir_config() which validates the
gitdir paths before adding the configs.

Suggested-by: Junio C Hamano <gitster@pobox.com>
Suggested-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/config/extensions.adoc b/Documentation/config/extensions.adoc
index e8d9d9a19a5fb62cc7b9ee15a9878e636016380b..2aef3315b1d2757084f4caa2dee4de460e37c751 100644 (file)
--- a/Documentation/config/extensions.adoc
+++ b/Documentation/config/extensions.adoc
@@ -93,8 +93,10 @@ Git will error out if a module does not have a corresponding
 `submodule.<name>.gitdir` set.
 +
 Existing (pre-extension) submodules need to be migrated by adding the missing
-config entries. This is done manually for now, e.g. for each submodule:
-`git config submodule.<name>.gitdir .git/modules/<name>`.
+config entries. This can be done manually, e.g. for each submodule:
+`git config submodule.<name>.gitdir .git/modules/<name>`, or via the
+`git submodule--helper migrate-gitdir-configs` command which iterates over all
+submodules and attempts to migrate them.
 +
 The extension can be enabled automatically for new repositories by setting
 `init.defaultSubmodulePathConfig` to `true`, for example by running

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index ef373525349c2a21ec945095747eda9ed9a30065..fa4f5cc15919f3c47f43b38c4f45d75ebfe94401 100644 (file)
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -1270,6 +1270,66 @@ static int module_gitdir(int argc, const char **argv, const char *prefix UNUSED,
        return 0;
 }
 
+static int module_migrate(int argc UNUSED, const char **argv UNUSED,
+                         const char *prefix UNUSED, struct repository *repo)
+{
+       struct strbuf module_dir = STRBUF_INIT;
+       DIR *dir;
+       struct dirent *de;
+       int repo_version = 0;
+
+       repo_git_path_append(repo, &module_dir, "modules/");
+
+       dir = opendir(module_dir.buf);
+       if (!dir)
+               die(_("could not open '%s'"), module_dir.buf);
+
+       while ((de = readdir(dir))) {
+               struct strbuf gitdir_path = STRBUF_INIT;
+               char *key;
+               const char *value;
+
+               if (is_dot_or_dotdot(de->d_name))
+                       continue;
+
+               strbuf_addf(&gitdir_path, "%s/%s", module_dir.buf, de->d_name);
+               if (!is_git_directory(gitdir_path.buf)) {
+                       strbuf_release(&gitdir_path);
+                       continue;
+               }
+               strbuf_release(&gitdir_path);
+
+               key = xstrfmt("submodule.%s.gitdir", de->d_name);
+               if (!repo_config_get_string_tmp(repo, key, &value)) {
+                       /* Already has a gitdir config, nothing to do. */
+                       free(key);
+                       continue;
+               }
+               free(key);
+
+               create_default_gitdir_config(de->d_name);
+       }
+
+       closedir(dir);
+       strbuf_release(&module_dir);
+
+       repo_config_get_int(the_repository, "core.repositoryformatversion", &repo_version);
+       if (repo_version == 0 &&
+           repo_config_set_gently(repo, "core.repositoryformatversion", "1"))
+               die(_("could not set core.repositoryformatversion to 1.\n"
+                     "Please set it for migration to work, for example:\n"
+                     "git config core.repositoryformatversion 1"));
+
+       if (repo_config_set_gently(repo, "extensions.submodulePathConfig", "true"))
+               die(_("could not enable submodulePathConfig extension. It is required\n"
+                     "for migration to work. Please enable it in the root repo:\n"
+                     "git config extensions.submodulePathConfig true"));
+
+       repo->repository_format_submodule_path_cfg = 1;
+
+       return 0;
+}
+
 struct sync_cb {
        const char *prefix;
        const char *super_prefix;
@@ -3653,6 +3713,7 @@ int cmd_submodule__helper(int argc,
                NULL
        };
        struct option options[] = {
+               OPT_SUBCOMMAND("migrate-gitdir-configs", &fn, module_migrate),
                OPT_SUBCOMMAND("gitdir", &fn, module_gitdir),
                OPT_SUBCOMMAND("clone", &fn, module_clone),
                OPT_SUBCOMMAND("add", &fn, module_add),

diff --git a/t/t7425-submodule-gitdir-path-extension.sh b/t/t7425-submodule-gitdir-path-extension.sh
index 03ac165de96477f96e4a91989f9a7bf48d95cc0d..89e2feab8b7c4bea9a3bccc127f0956a251bb52e 100755 (executable)
--- a/t/t7425-submodule-gitdir-path-extension.sh
+++ b/t/t7425-submodule-gitdir-path-extension.sh
@@ -279,4 +279,71 @@ test_expect_success '`git clone --recurse-submodules` respects init.defaultSubmo
        )
 '
 
+test_expect_success 'submodule--helper migrates legacy modules' '
+       (
+               cd upstream &&
+
+               # previous submodules exist and were not migrated yet
+               test_must_fail git config submodule.sub1.gitdir &&
+               test_must_fail git config submodule.sub2.gitdir &&
+               test_path_is_dir .git/modules/sub1 &&
+               test_path_is_dir .git/modules/sub2 &&
+
+               # run migration
+               git submodule--helper migrate-gitdir-configs &&
+
+               # test that migration worked
+               git config submodule.sub1.gitdir >actual &&
+               echo ".git/modules/sub1" >expect &&
+               test_cmp expect actual &&
+               git config submodule.sub2.gitdir >actual &&
+               echo ".git/modules/sub2" >expect &&
+               test_cmp expect actual &&
+
+               # repository extension is enabled after migration
+               git config extensions.submodulePathConfig >actual &&
+               echo "true" >expect &&
+               test_cmp expect actual
+       )
+'
+
+test_expect_success '`git clone --recurse-submodules` works after migration' '
+       test_when_finished "rm -rf repo-clone-recursive" &&
+
+       # test with extension disabled after the upstream repo was migrated
+       git clone --recurse-submodules upstream repo-clone-recursive &&
+       (
+               cd repo-clone-recursive &&
+
+               # init.defaultSubmodulePathConfig was disabled before clone, so
+               # the repo extension config should also be off, the migration ignored
+               test_must_fail git config extensions.submodulePathConfig &&
+
+               # modules should look like there was no migration done
+               test_must_fail git config submodule.sub1.gitdir &&
+               test_must_fail git config submodule.sub2.gitdir &&
+               test_path_is_dir .git/modules/sub1 &&
+               test_path_is_dir .git/modules/sub2
+       ) &&
+       rm -rf repo-clone-recursive &&
+
+       # enable the extension, then retry the clone
+       test_config_global init.defaultSubmodulePathConfig true &&
+       git clone --recurse-submodules upstream repo-clone-recursive &&
+       (
+               cd repo-clone-recursive &&
+
+               # repository extension is enabled
+               git config extensions.submodulePathConfig >actual &&
+               echo "true" >expect &&
+               test_cmp expect actual &&
+
+               # gitdir configs exist for submodules
+               git config submodule.sub1.gitdir &&
+               git config submodule.sub2.gitdir &&
+               test_path_is_dir .git/modules/sub1 &&
+               test_path_is_dir .git/modules/sub2
+       )
+'
+
 test_done