Fix moving issues API failing when text includes commit URLs

When a issue is moved from one project to another, all associated
Markdown text is rewritten in the context of the new project. If the
note contained a link to a commit URL, `CommitRewriter#rewrite` would
fail because `Commit#link_reference_pattern` would match `nil` `commit`
values in the HTML generated from the Markdown. These `nil` values were
passed along to `Project#commits_by` because `Commit#reference_valid?`
was always returning `true`.

To prevent this issue from happening, we tighten up the check for
`Commit#reference_valid?` to look for valid SHA values.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/66666

1 files changed, 18 insertions, 0 deletions

diff --git a/spec/models/commit_spec.rb b/spec/models/commit_spec.rb
index 7b35c2ffd36..5ef824b9950 100644
--- a/spec/models/commit_spec.rb
+++ b/spec/models/commit_spec.rb
@@ -192,6 +192,24 @@ describe Commit do
     end
   end
 
+  describe '.reference_valid?' do
+    using RSpec::Parameterized::TableSyntax
+
+    where(:ref, :result) do
+      '1234567' | true
+      '123456' | false
+      '1' | false
+      '0' * 40 | true
+      'c1acaa58bbcbc3eafe538cb8274ba387047b69f8' | true
+      'H1acaa58bbcbc3eafe538cb8274ba387047b69f8' | false
+      nil | false
+    end
+
+    with_them do
+      it { expect(described_class.reference_valid?(ref)).to eq(result) }
+    end
+  end
+
   describe '#reference_link_text' do
     let(:project) { create(:project, :repository, path: 'sample-project') }