The merge request widget has a section that includes which issues may be
closed or mentioned based on the merge request description. The problem
is that rendering and redacting Markdown can be expensive, especially
since the browser polls for the data every 10 seconds.

Since these links don't change much and are just nice to have, we only
load them on first page load. The frontend will use the existing data if
the data doesn't appear on subsequent requests.

This saves about 30% of the rendering time of this endpoint, which adds
up to significant savings considering that
`MergeRequestsController#show.json` is called over a million times a day
on GitLab.com.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/63546

We have one auto merge strategy today - Merge When Pipeline
Succeeds.

In order to add more strategies for Merge Train feature,
we abstract the architecture to be more extensible.

Removed arguments

Fix spec

Thong Kuah authored 5 years ago and James Lopez committed 5 years ago

- rewords examples starting with 'should'
- rewords examples starting with 'it'

Note: I had to manually fixup "onlies" to "only"

This is for merge request pipelines

Allow incomplete commit records to load their full data from gitaly.

Commits can be based on a Hash of data retrieved from PostgreSQL, and
this data can be intentionally incomplete in order to save space.

A new method #gitaly? has been added to Gitlab::Git::Commit, which
returns true if the underlying data source of the Commit is a
Gitaly::GitCommit.

CommitCollection now has a method #enrich which replaces non-gitaly
commits in place with commits from gitaly.

CommitCollection#without_merge_commits has been updated to call this
method, as in order to determine a merge commit we need to have parent
data.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/58805

Revert "Merge branch '58805-allow-incomplete-commit-data-to-be-fetched-from-collection' into 'master'"

This reverts merge request !26144

Allow incomplete commit records to load their full data from gitaly.

Commits can be based on a Hash of data retrieved from PostgreSQL, and
this data can be intentionally incomplete in order to save space.

A new method #gitaly? has been added to Gitlab::Git::Commit, which
returns true if the underlying data source of the Commit is a
Gitaly::GitCommit.

CommitCollection now has a method #enrich which replaces non-gitaly
commits in place with commits from gitaly.

CommitCollection#without_merge_commits has been updated to call this
method, as in order to determine a merge commit we need to have parent
data.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/58805

This removes the `ForkedProjectLink` model that has been replaced by
the `ForkNetworkMember` and `ForkNetwork` combination. All existing
relations have been adjusted to use these new models.

The `forked_project_link` table has been dropped.

The "Forks" count on the admin dashboard has been updated to count all
`ForkNetworkMember` rows and deduct the number of `ForkNetwork`
rows. This is because now the "root-project" of a fork network also
has a `ForkNetworkMember` row. This count could become inaccurate when
the root of a fork network is deleted.

Closes #47460

The MergeRequestWidgetEntity is used a lot in AJAX requests, and shaving
that git operation will hopefully translate in a performance improvement

When a project uses fast-forward merging strategy user has
to rebase MRs to target branch before it can be merged.
Now user can do rebase in UI by clicking 'Rebase' button
instead of doing rebase locally.

This feature was already present in EE, this is only backport
of the feature to CE. Couple of changes:
* removed rebase license check
* renamed migration (changed timestamp)

Closes #40301

requests