Merge branch 'disable-ref-generation-in-code-blocks' into 'master'

Disable reference generation in preformatted/code blocks

### Summary

If a user adds text in code or preformatted text via Markdown or HTML that contains `#XXX`, the system adds a note that issue `XXX` was mentioned. This is particularly annoying because we often list gdb backtrace dumps into our issues, and many issues get mentioned as a result. For example:

```
(gdb) bt
#0  0x00000000004004c4 in second () at main.cc:6
#1  0x00000000004004d2 in first () at main.cc:11
#2  0x00000000004004dd in main () at main.cc:17
(gdb)
```

### Steps to reproduce

1. In an issue, write the above text using Markdown or HTML tags (e.g. `<code>`, `<pre>`).
2. Observe that [issue 1](https://gitlab.com/gitlab-org/gitlab-ce/issues/1) and [issue 2](https://gitlab.com/gitlab-org/gitlab-ce/issues/2) have a note that says they were mentioned.

### Expected behavior

Everything enclosed in the code blocks should be ignored as references.

### Observed behavior

Issues get referenced unnecessarily.

### Fix

I've made `reference_extractor.rb` strip out HTML and Markdown blocks before processing. I considered running the raw text through the entire Markdown processor, but this seems overkill and perhaps could lead to some unintended side effects.

See merge request !365

1 files changed, 20 insertions, 0 deletions

diff --git a/spec/lib/gitlab/reference_extractor_spec.rb b/spec/lib/gitlab/reference_extractor_spec.rb
index 5ebe44f6fb7..b3f4bb5aeda 100644
--- a/spec/lib/gitlab/reference_extractor_spec.rb
+++ b/spec/lib/gitlab/reference_extractor_spec.rb
@@ -50,6 +50,26 @@ describe Gitlab::ReferenceExtractor do
     expect(text).to eq('issue #123 is just the worst, @user')
   end
 
+  it 'extracts no references for <pre>..</pre> blocks' do
+    subject.analyze("<pre>def puts '#1 issue'\nend\n</pre>```", nil)
+    expect(subject.issues).to be_blank
+  end
+
+  it 'extracts no references for <code>..</code> blocks' do
+    subject.analyze("<code>def puts '!1 request'\nend\n</code>```", nil)
+    expect(subject.merge_requests).to be_blank
+  end
+
+  it 'extracts no references for code blocks with language' do
+    subject.analyze("this code:\n```ruby\ndef puts '#1 issue'\nend\n```", nil)
+    expect(subject.issues).to be_blank
+  end
+
+  it 'extracts issue references for invalid code blocks' do
+    subject.analyze('test: ```this one talks about issue #1234```', nil)
+    expect(subject.issues).to eq([{ project: nil, id: '1234' }])
+  end
+
   it 'handles all possible kinds of references' do
     accessors = Gitlab::Markdown::TYPES.map { |t| "#{t}s".to_sym }
     expect(subject).to respond_to(*accessors)