From: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
To prevent long blocking time during a 'git fetch' call, a user
may want to set up a schedule for background 'git fetch' processes.
However, these runs will update the refs/remotes branches due to
the default refspec set in the config when Git adds a remote.
Hence the user will not notice when remote refs are updated during
their foreground fetches. In fact, they may _want_ those refs to
stay put so they can work with the refs from their last foreground
fetch call.
This can be accomplished by overriding the configured refspec using
'--refmap=' along with a custom refspec:
git fetch <remote> --refmap= +refs/heads/*:refs/hidden/<remote>/*
to populate a custom ref space and download a pack of the new
reachable objects. This kind of call allows a few things to happen:
1. We download a new pack if refs have updated.
2. Since the refs/hidden branches exist, GC will not remove the
newly-downloaded data.
3. With fetch.writeCommitGraph enabled, the refs/hidden refs are
used to update the commit-graph file.
To avoid the refs/hidden directory from filling without bound, the
--prune option can be included. When providing a refspec like this,
the --prune option does not delete remote refs and instead only
deletes refs in the target refspace.
Update the documentation to clarify how '--refmap=""' works and
create tests to guarantee this behavior remains in the future.
Signed-off-by: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
---
fetch: document and test '--refmap=""'
Thanks for all the feedback leading to absolutely no code change. It's
good we already have the flexibility for this. I'm a bit embarrassed
that I did not discover this, so perhaps this doc change and new tests
will help clarify the behavior.
Thanks, -Stolee
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-532%2Fderrickstolee%2Ffetch-no-update-remote-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-532/derrickstolee/fetch-no-update-remote-v2
Pull-Request: https://github.com/gitgitgadget/git/pull/532
Range-diff vs v1:
1: 26f13ea5f5 ! 1: 51c6221a31 fetch: add --no-update-remote-refs
@@ -1,20 +1,20 @@
Author: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
- fetch: add --no-update-remote-refs
+ fetch: document and test --refmap=""
To prevent long blocking time during a 'git fetch' call, a user
may want to set up a schedule for background 'git fetch' processes.
- However, these runs will update the refs/remotes branches, and
- hence the user will not notice when remote refs are updated during
+ However, these runs will update the refs/remotes branches due to
+ the default refspec set in the config when Git adds a remote.
+ Hence the user will not notice when remote refs are updated during
their foreground fetches. In fact, they may _want_ those refs to
stay put so they can work with the refs from their last foreground
fetch call.
- Add a --[no-]update-remote-refs option to 'git fetch' which defaults
- to the existing behavior of updating the remote refs. This allows
- a user to run
+ This can be accomplished by overriding the configured refspec using
+ '--refmap=' along with a custom refspec:
- git fetch <remote> --no-update-remote-refs +refs/heads/*:refs/hidden/*
+ git fetch <remote> --refmap= +refs/heads/*:refs/hidden/<remote>/*
to populate a custom ref space and download a pack of the new
reachable objects. This kind of call allows a few things to happen:
@@ -30,9 +30,8 @@
the --prune option does not delete remote refs and instead only
deletes refs in the target refspace.
- Note: with the default refpsec, the --prune option will override
- the --no-update-remote-refs option and will delete the refs that
- do not exist on the remote.
+ Update the documentation to clarify how '--refmap=""' works and
+ create tests to guarantee this behavior remains in the future.
Signed-off-by: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
@@ -40,50 +39,17 @@
--- a/Documentation/fetch-options.txt
+++ b/Documentation/fetch-options.txt
@@
- 'git-pull' the --ff-only option will still check for forced updates
- before attempting a fast-forward update. See linkgit:git-config[1].
+ specified refspec (can be given more than once) to map the
+ refs to remote-tracking branches, instead of the values of
+ `remote.*.fetch` configuration variables for the remote
+- repository. See section on "Configured Remote-tracking
++ repository. Providing an empty `<refspec>` to the
++ `--refmap` option causes Git to ignore the configured
++ refspecs and rely entirely on the refspecs supplied as
++ command-line arguments. See section on "Configured Remote-tracking
+ Branches" for details.
-+--no-update-remote-refs::
-+ By default, git updates the `refs/remotes/` refspace with the refs
-+ advertised by the remotes during a `git fetch` command. With this
-+ option, those refs will be ignored. If the `--prune` option is
-+ specified and the default refpsec is used, then a ref that does not
-+ appear in the remote will still be deleted from refs/remotes.
-+
- -4::
- --ipv4::
- Use IPv4 addresses only, ignoring IPv6 addresses.
-
- diff --git a/builtin/fetch.c b/builtin/fetch.c
- --- a/builtin/fetch.c
- +++ b/builtin/fetch.c
-@@
- static struct string_list server_options = STRING_LIST_INIT_DUP;
- static struct string_list negotiation_tip = STRING_LIST_INIT_NODUP;
- static int fetch_write_commit_graph = -1;
-+static int update_remote_refs = 1;
-
- static int git_fetch_config(const char *k, const char *v, void *cb)
- {
-@@
- N_("check for forced-updates on all updated branches")),
- OPT_BOOL(0, "write-commit-graph", &fetch_write_commit_graph,
- N_("write the commit-graph after fetching")),
-+ OPT_BOOL(0, "update-remote-refs", &update_remote_refs,
-+ N_("update the refs/remotes/ refspace")),
- OPT_END()
- };
-
-@@
- const char *pretty_ref = prettify_refname(ref->name);
- int fast_forward = 0;
-
-+ if (!update_remote_refs && starts_with(ref->name, "refs/remotes/"))
-+ return 0;
-+
- type = oid_object_info(the_repository, &ref->new_oid, NULL);
- if (type < 0)
- die(_("object %s not found"), oid_to_hex(&ref->new_oid));
+ -t::
diff --git a/t/t5510-fetch.sh b/t/t5510-fetch.sh
--- a/t/t5510-fetch.sh
@@ -92,13 +58,13 @@
git rev-parse sometag
'
-+test_expect_success 'fetch --no-update-remote-refs keeps existing refs' '
++test_expect_success '--refmap="" ignores configured refspec' '
+ cd "$TRASH_DIRECTORY" &&
+ git clone "$D" remote-refs &&
+ git -C remote-refs rev-parse remotes/origin/master >old &&
+ git -C remote-refs update-ref refs/remotes/origin/master master~1 &&
+ git -C remote-refs rev-parse remotes/origin/master >new &&
-+ git -C remote-refs fetch --no-update-remote-refs origin &&
++ git -C remote-refs fetch --refmap= origin "+refs/heads/*:refs/hidden/origin/*" &&
+ git -C remote-refs rev-parse remotes/origin/master >actual &&
+ test_cmp new actual &&
+ git -C remote-refs fetch origin &&
@@ -106,13 +72,13 @@
+ test_cmp old actual
+'
+
-+test_expect_success 'fetch --no-update-remote-refs --prune with refspec' '
++test_expect_success '--refmap="" and --prune' '
+ git -C remote-refs update-ref refs/remotes/origin/foo/otherbranch master &&
+ git -C remote-refs update-ref refs/hidden/foo/otherbranch master &&
-+ git -C remote-refs fetch --prune --no-update-remote-refs origin +refs/heads/*:refs/hidden/* &&
++ git -C remote-refs fetch --prune --refmap="" origin +refs/heads/*:refs/hidden/* &&
+ git -C remote-refs rev-parse remotes/origin/foo/otherbranch &&
+ test_must_fail git -C remote-refs rev-parse refs/hidden/foo/otherbranch &&
-+ git -C remote-refs fetch --prune --no-update-remote-refs origin &&
++ git -C remote-refs fetch --prune origin &&
+ test_must_fail git -C remote-refs rev-parse remotes/origin/foo/otherbranch
+'
+
Documentation/fetch-options.txt | 5 ++++-
t/t5510-fetch.sh | 24 ++++++++++++++++++++++++
2 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/Documentation/fetch-options.txt b/Documentation/fetch-options.txt
index a2f78624a2..a115a1ae0e 100644
--- a/Documentation/fetch-options.txt
+++ b/Documentation/fetch-options.txt
@@ -139,7 +139,10 @@ ifndef::git-pull[]
specified refspec (can be given more than once) to map the
refs to remote-tracking branches, instead of the values of
`remote.*.fetch` configuration variables for the remote
- repository. See section on "Configured Remote-tracking
+ repository. Providing an empty `<refspec>` to the
+ `--refmap` option causes Git to ignore the configured
+ refspecs and rely entirely on the refspecs supplied as
+ command-line arguments. See section on "Configured Remote-tracking
Branches" for details.
-t::
diff --git a/t/t5510-fetch.sh b/t/t5510-fetch.sh
index 4b60282689..5f8f1c287f 100755
--- a/t/t5510-fetch.sh
+++ b/t/t5510-fetch.sh
@@ -174,6 +174,30 @@ test_expect_success 'fetch --prune --tags with refspec prunes based on refspec'
git rev-parse sometag
'
+test_expect_success '--refmap="" ignores configured refspec' '
+ cd "$TRASH_DIRECTORY" &&
+ git clone "$D" remote-refs &&
+ git -C remote-refs rev-parse remotes/origin/master >old &&
+ git -C remote-refs update-ref refs/remotes/origin/master master~1 &&
+ git -C remote-refs rev-parse remotes/origin/master >new &&
+ git -C remote-refs fetch --refmap= origin "+refs/heads/*:refs/hidden/origin/*" &&
+ git -C remote-refs rev-parse remotes/origin/master >actual &&
+ test_cmp new actual &&
+ git -C remote-refs fetch origin &&
+ git -C remote-refs rev-parse remotes/origin/master >actual &&
+ test_cmp old actual
+'
+
+test_expect_success '--refmap="" and --prune' '
+ git -C remote-refs update-ref refs/remotes/origin/foo/otherbranch master &&
+ git -C remote-refs update-ref refs/hidden/foo/otherbranch master &&
+ git -C remote-refs fetch --prune --refmap="" origin +refs/heads/*:refs/hidden/* &&
+ git -C remote-refs rev-parse remotes/origin/foo/otherbranch &&
+ test_must_fail git -C remote-refs rev-parse refs/hidden/foo/otherbranch &&
+ git -C remote-refs fetch --prune origin &&
+ test_must_fail git -C remote-refs rev-parse remotes/origin/foo/otherbranch
+'
+
test_expect_success 'fetch tags when there is no tags' '
cd "$D" &&
base-commit: d0654dc308b0ba76dd8ed7bbb33c8d8f7aacd783
--
gitgitgadget
