tree 7f1f0792f9435263a4e85a7effd97834164de32d
parent e7cac4bca6b8e4276a5a64287653b5c56555d6f4
author Gavin Mak <gavinmak@google.com> 1781565784 +0000
committer gerrit-scoped@luci-project-accounts.iam.gserviceaccount.com <gerrit-scoped@luci-project-accounts.iam.gserviceaccount.com> 1782850815 -0700

sync: Implement fetchcmd for standard Git layouts

Introduce support for `repo.fetchcmd` configuration, allowing users to
specify a custom command to fetch project data instead of
`_RemoteFetch`.

When `repo.fetchcmd` is specified, `repo` will execute it instead of
`_RemoteFetch` during the network half of sync. Note that
`repo.fetchcmd` requires `repo.uselocalgitdirs` to be enabled.

The command is executed in a subshell with project-context environment
variables, including the new `REPO_TREV` (target revision resolved to a
commit hash) and `REPO_PROJECT_FETCH_URL`.

After execution, `repo` verifies that the target commit is available and
that the tracking ref and FETCH_HEAD are correctly updated.

Tested with:
```
> ~/git-repo/repo init -u https://android-review.googlesource.com/platform/manifest \
    --repo-url file:///usr/local/google/home/gavinmak/git-repo \
    --groups developers \
    --no-repo-verify \
    --use-local-gitdirs
...

> git config --file .repo/manifests.git/config repo.fetchcmd 'mkdir -p $REPO_PATH && cd $REPO_PATH && if [ ! -d .git ]; then git init && git remote add aosp $REPO_PROJECT_FETCH_URL; fi && git fetch aosp $REPO_TREV && git reset --hard $REPO_TREV && mkdir -p .git/refs/remotes/aosp && echo $REPO_TREV > .git/refs/remotes/aosp/main && echo $REPO_TREV > .git/FETCH_HEAD'

> ~/git-repo/repo sync -j32
warning: repo is not tracking a remote branch, so it will not receive updates; run `repo init --repo-rev=stable` to fix.
You are currently enrolled in Git submodules experiment (go/android-submodules-quickstart).  Use --no-use-superproject to override.

Syncing: 100% (4/4), done in 1m15.686s
Finalizing sync state...
repo sync has finished successfully.
```

Bug: 513329573
Change-Id: I754d3f3c78e86fdeee1a72115297a75b571bc497
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/583883
Reviewed-by: Becky Siegel <beckysiegel@google.com>
Tested-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Gavin Mak <gavinmak@google.com>