git/submodule.c, branch v2.36.2

Merge branch 'jt/reset-grafts-when-resetting-shallow'

2022-03-29T19:22:03Z

When "shallow" information is updated, we forgot to update the in-core equivalent, which has been corrected. * jt/reset-grafts-when-resetting-shallow: shallow: reset commit grafts when shallow is reset

shallow: reset commit grafts when shallow is reset

2022-03-18T00:44:38Z

When reset_repository_shallow() is called, Git clears its cache of shallow information, so that if shallow information is re-requested, Git will read fresh data from disk instead of reusing its stale cached data. However, the cache of commit grafts is not likewise cleared, even though there are commit grafts created from shallow information. This means that if on-disk shallow information were to be updated and then a commit-graft-using codepath were run (for example, a revision walk), Git would be using stale commit graft information. This can be seen from the test in this patch, in which Git performs a revision walk (to check for changed submodules) after a fetch with --update-shallow. Therefore, clear the cache of commit grafts whenever reset_repository_shallow() is called. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

submodule: fix latent check_has_commit() bug

2022-03-16T23:08:59Z

When check_has_commit() is called on a missing submodule, initialization of the struct repository fails, but it attempts to clear the struct anyway (which is a fatal error). This bug is masked by its only caller, submodule_has_commits(), first calling add_submodule_odb(). The latter fails if the submodule does not exist, making submodule_has_commits() exit early and not invoke check_has_commit(). Fix this bug, and because calling add_submodule_odb() is no longer necessary as of 13a2f620b2 (submodule: pass repo to check_has_commit(), 2021-10-08), remove that call too. This is the last caller of add_submodule_odb(), so remove that function. (Submodule ODBs are still added as alternates via add_submodule_odb_by_path().) Signed-off-by: Glen Choo Signed-off-by: Junio C Hamano

fetch: fetch unpopulated, changed submodules

2022-03-16T23:08:59Z

"git fetch --recurse-submodules" only considers populated submodules (i.e. submodules that can be found by iterating the index), which makes "git fetch" behave differently based on which commit is checked out. As a result, even if the user has initialized all submodules correctly, they may not fetch the necessary submodule commits, and commands like "git checkout --recurse-submodules" might fail. Teach "git fetch" to fetch cloned, changed submodules regardless of whether they are populated. This is in addition to the current behavior of fetching populated submodules (which is always attempted regardless of what was fetched in the superproject, or even if nothing was fetched in the superproject). A submodule may be encountered multiple times (via the list of populated submodules or via the list of changed submodules). When this happens, "git fetch" only reads the 'populated copy' and ignores the 'changed copy'. Amend the verify_fetch_result() test helper so that we can assert on which 'copy' is being read. Signed-off-by: Glen Choo Signed-off-by: Junio C Hamano

submodule: move logic into fetch_task_create()

2022-03-08T00:51:03Z

get_fetch_task() gets a fetch task by iterating the index; a future commit will introduce a similar function, get_fetch_task_from_changed(), that gets a fetch task from the list of changed submodules. Both functions are similar in that they need to: * create a fetch task * initialize the submodule repo for the fetch task * determine the default recursion mode Move all of this logic into fetch_task_create() so that it is no longer split between fetch_task_create() and get_fetch_task(). This will make it easier to share code with get_fetch_task_from_changed(). Signed-off-by: Glen Choo Signed-off-by: Junio C Hamano

submodule: extract get_fetch_task()

2022-03-08T00:51:03Z

get_next_submodule() configures the parallel submodule fetch by performing two functions: * iterate the index to find submodules * configure the child processes to fetch the submodules found in the previous step Extract the index iterating code into an iterator function, get_fetch_task(), so that get_next_submodule() is agnostic of how to find submodules. This prepares for a subsequent commit will teach the fetch machinery to also iterate through the list of changed submodules (in addition to the index). Signed-off-by: Glen Choo Signed-off-by: Junio C Hamano

submodule: store new submodule commits oid_array in a struct

2022-03-08T00:51:03Z

This commit prepares for a future commit that will teach `git fetch --recurse-submodules` how to fetch submodules that are present in /modules, but are not populated. To do this, we need to store more information about the changed submodule so that we can read the submodule configuration from the superproject commit instead of the filesystem. Refactor the changed submodules string_list.util to hold a struct instead of an oid_array. This struct only holds the new_commits oid_array for now; more information will be added later. Signed-off-by: Glen Choo Signed-off-by: Junio C Hamano

submodule: inline submodule_commits() into caller

2022-03-08T00:51:03Z

When collecting the string_list of changed submodule names, the new submodules commits are stored in the string_list_item.util as an oid_array. A subsequent commit will replace the oid_array with a struct that has more information. Prepare for this change by inlining submodule_commits() (which inserts into the string_list and initializes the string_list_item.util) into its only caller so that the code is easier to refactor later. Signed-off-by: Glen Choo Signed-off-by: Junio C Hamano

submodule: make static functions read submodules from commits

2022-03-08T00:51:03Z

A future commit will teach "fetch --recurse-submodules" to fetch unpopulated submodules. To prepare for this, teach the necessary static functions how to read submodules from superproject commits using a "treeish_name" argument (instead of always reading from the index and filesystem) but do not actually change where submodules are read from. Submodules will be read from commits when we fetch unpopulated submodules. Signed-off-by: Glen Choo Signed-off-by: Junio C Hamano

branch: add --recurse-submodules option for branch creation

2022-02-04T16:16:39Z

To improve the submodules UX, we would like to teach Git to handle branches in submodules. Start this process by teaching "git branch" the --recurse-submodules option so that "git branch --recurse-submodules topic" will create the `topic` branch in the superproject and its submodules. Although this commit does not introduce breaking changes, it does not work well with existing --recurse-submodules commands because "git branch --recurse-submodules" writes to the submodule ref store, but most commands only consider the superproject gitlink and ignore the submodule ref store. For example, "git checkout --recurse-submodules" will check out the commits in the superproject gitlinks (and put the submodules in detached HEAD) instead of checking out the submodule branches. Because of this, this commit introduces a new configuration value, `submodule.propagateBranches`. The plan is for Git commands to prioritize submodule ref store information over superproject gitlinks if this value is true. Because "git branch --recurse-submodules" writes to submodule ref stores, for the sake of clarity, it will not function unless this configuration value is set. This commit also includes changes that support working with submodules from a superproject commit because "branch --recurse-submodules" (and future commands) need to read .gitmodules and gitlinks from the superproject commit, but submodules are typically read from the filesystem's .gitmodules and the index's gitlinks. These changes are: * add a submodules_of_tree() helper that gives the relevant information of an in-tree submodule (e.g. path and oid) and initializes the repository * add is_tree_submodule_active() by adding a treeish_name parameter to is_submodule_active() * add the "submoduleNotUpdated" advice to advise users to update the submodules in their trees Incidentally, fix an incorrect usage string that combined the 'list' usage of git branch (-l) with the 'create' usage; this string has been incorrect since its inception, a8dfd5eac4 (Make builtin-branch.c use parse_options., 2007-10-07). Helped-by: Jonathan Tan Signed-off-by: Glen Choo Reviewed-by: Jonathan Tan Signed-off-by: Junio C Hamano