Fix closing issue default pattern

* (Suf)fix #51085 :-)
Signed-off-by: Samuele Kaplun <kaplun@protonmail.com>

changelogs/unreleased/fix-closing-issues.yml

+---
+title: Fix closing issue default pattern
+merge_request: 21531
+author: Samuele Kaplun
+type: fixed

config/gitlab.yml.example

@@ -94,7 +94,7 @@ production: &base
     # This happens when the commit is pushed or merged into the default branch of a project.
     # When not specified the default issue_closing_pattern as specified below will be used.
     # Tip: you can test your closing pattern at http://rubular.com.
-    # issue_closing_pattern: '((?:[Cc]los(?:e[sd]?|ing)|[Ff]ix(?:e[sd]|ing)?|[Rr]esolv(?:e[sd]?|ing)|[Ii]mplement(?:s|ed|ing)?)(:?) +(?:(?:issues? +)?%{issue_ref}(?:(?:, *| +and +)?)|([A-Z][A-Z0-9_]+-\d+))+)'
+    # issue_closing_pattern: '\b((?:[Cc]los(?:e[sd]?|ing)|\b[Ff]ix(?:e[sd]|ing)?|\b[Rr]esolv(?:e[sd]?|ing)|\b[Ii]mplement(?:s|ed|ing)?)(:?) +(?:(?:issues? +)?%{issue_ref}(?:(?:, *| +and +)?)|([A-Z][A-Z0-9_]+-\d+))+)'
 
     ## Default project features settings
     default_projects_features:

config/initializers/1_settings.rb

@@ -136,7 +136,7 @@ Settings.gitlab['signup_enabled'] ||= true if Settings.gitlab['signup_enabled'].
 Settings.gitlab['signin_enabled'] ||= true if Settings.gitlab['signin_enabled'].nil?
 Settings.gitlab['restricted_visibility_levels'] = Settings.__send__(:verify_constant_array, Gitlab::VisibilityLevel, Settings.gitlab['restricted_visibility_levels'], [])
 Settings.gitlab['username_changing_enabled'] = true if Settings.gitlab['username_changing_enabled'].nil?
-Settings.gitlab['issue_closing_pattern'] = '((?:[Cc]los(?:e[sd]?|ing)|[Ff]ix(?:e[sd]|ing)?|[Rr]esolv(?:e[sd]?|ing)|[Ii]mplement(?:s|ed|ing)?)(:?) +(?:(?:issues? +)?%{issue_ref}(?:(?: *,? +and +| *,? *)?)|([A-Z][A-Z0-9_]+-\d+))+)' if Settings.gitlab['issue_closing_pattern'].nil?
+Settings.gitlab['issue_closing_pattern'] = '\b((?:[Cc]los(?:e[sd]?|ing)|\b[Ff]ix(?:e[sd]|ing)?|\b[Rr]esolv(?:e[sd]?|ing)|\b[Ii]mplement(?:s|ed|ing)?)(:?) +(?:(?:issues? +)?%{issue_ref}(?:(?: *,? +and +| *,? *)?)|([A-Z][A-Z0-9_]+-\d+))+)' if Settings.gitlab['issue_closing_pattern'].nil?
 Settings.gitlab['default_projects_features'] ||= {}
 Settings.gitlab['webhook_timeout'] ||= 10
 Settings.gitlab['max_attachment_size'] ||= 10

doc/administration/issue_closing_pattern.md

@@ -28,7 +28,7 @@ Because Rubular doesn't understand `%{issue_ref}`, you can replace this by
    expression of your liking:
 
     ```ruby
-    gitlab_rails['gitlab_issue_closing_pattern'] = "((?:[Cc]los(?:e[sd]|ing)|[Ff]ix(?:e[sd]|ing)?) +(?:(?:issues? +)?%{issue_ref}(?:(?:, *| +and +)?))+)"
+    gitlab_rails['gitlab_issue_closing_pattern'] = "\b((?:[Cc]los(?:e[sd]|ing)|\b[Ff]ix(?:e[sd]|ing)?) +(?:(?:issues? +)?%{issue_ref}(?:(?:, *| +and +)?))+)"
     ```
 1. [Reconfigure] GitLab for the changes to take effect.
 
@@ -38,7 +38,7 @@ Because Rubular doesn't understand `%{issue_ref}`, you can replace this by
 1. Change the value of `issue_closing_pattern`:
 
     ```yaml
-    issue_closing_pattern: "((?:[Cc]los(?:e[sd]|ing)|[Ff]ix(?:e[sd]|ing)?) +(?:(?:issues? +)?%{issue_ref}(?:(?:, *| +and +)?))+)"
+    issue_closing_pattern: "\b((?:[Cc]los(?:e[sd]|ing)|\b[Ff]ix(?:e[sd]|ing)?) +(?:(?:issues? +)?%{issue_ref}(?:(?:, *| +and +)?))+)"
     ```
 
 1. [Restart] GitLab for the changes to take effect.

spec/lib/gitlab/closing_issue_extractor_spec.rb

@@ -338,6 +338,13 @@ describe Gitlab::ClosingIssueExtractor do
       end
     end
 
+    context "with an invalid keyword such as suffix insted of fix" do
+      it do
+        message = "suffix #{reference}"
+        expect(subject.closed_by_message(message)).to eq([])
+      end
+    end
+
     context 'with multiple references' do
       let(:other_issue) { create(:issue, project: project) }
       let(:third_issue) { create(:issue, project: project) }