Rename MsgPattern hook to MessageFormat

A bit nit-picky, but we've already established a convention of using
"Message" instead of the "Msg" short form (CommitMsg doesn't count as it
is a separate naming scheme brought over from Git). Also, I personally
find "Format" a better descriptor than "Pattern", as the later implies
some sort of repetition, where the former is simply "the way in which
something is arranged or set out." (definition)

I updated the implementation to not use instance variables (since there
was no need).

Author: sds

CHANGELOG.md

@@ -9,6 +9,8 @@
 * Improve error message output when there is a problem processing messages
   via `extract_messages` pre-commit hook helper
 * Fix `Minitest` pre-push hook to include all test files
+* Add `MessageFormat` commit-msg hook to validate commit messages against
+  a regex pattern
 
 ## 0.32.0.rc1
 

README.md

@@ -378,12 +378,12 @@ follow [proper formatting guidelines](http://tbaggery.com/2008/04/19/a-note-abou
 * [`*`EmptyMessage](lib/overcommit/hook/commit_msg/empty_message.rb)
 * [GerritChangeId](lib/overcommit/hook/commit_msg/gerrit_change_id.rb)
 * [HardTabs](lib/overcommit/hook/commit_msg/hard_tabs.rb)
+* [MessageFormat](lib/overcommit/hook/commit_msg/message_format.rb)
 * [RussianNovel](lib/overcommit/hook/commit_msg/russian_novel.rb)
 * [`*`SingleLineSubject](lib/overcommit/hook/commit_msg/single_line_subject.rb)
 * [SpellCheck](lib/overcommit/hook/commit_msg/spell_check.rb)
 * [`*`TextWidth](lib/overcommit/hook/commit_msg/text_width.rb)
 * [`*`TrailingPeriod](lib/overcommit/hook/commit_msg/trailing_period.rb)
-* [`*`MsgPattern](lib/overcommit/hook/commit_msg/msg_pattern.rb)
 
 ### PostCheckout
 

config/default.yml

@@ -78,6 +78,13 @@ CommitMsg:
     enabled: false
     description: 'Checking for hard tabs'
 
+  MessageFormat:
+    enabled: false
+    description: 'Checking commit message matches expected pattern'
+    pattern: '(.+)[|](.+)[|](.+)'
+    expected_pattern_message: '<Issue Id> | <Commit Message Description> | <Developer(s)>'
+    sample_message: 'DEFECT-1234 | Refactored Onboarding flow | John Doe'
+
   RussianNovel:
     enabled: false
     description: 'Checking length of commit message'
@@ -103,13 +110,6 @@ CommitMsg:
     enabled: true
     description: 'Checking for trailing periods in subject'
 
-  MsgPattern:
-    enabled: false
-    description: 'Checking for message pattern'
-    pattern: '(.+)[|](.+)[|](.+)'
-    expected_pattern_message: '<Issue Id> | <Commit Message Description> | <Developer(s)>'
-    sample_message: 'DEFECT-1234 | Refactored Onboarding flow | John Doe'
-
 # Hooks that are run after `git commit` is executed, before the commit message
 # editor is displayed. These hooks are ideal for syntax checkers, linters, and
 # other checks that you want to run before you allow a commit object to be

lib/overcommit/hook/commit_msg/msg_pattern.rb lib/overcommit/hook/commit_msg/message_format.rb

@@ -1,12 +1,11 @@
 module Overcommit::Hook::CommitMsg
-  # Ensures the commit message follows a specific pattern for analytical purposes
-  class MsgPattern < Base
+  # Ensures the commit message follows a specific format.
+  class MessageFormat < Base
     def run
-      return :fail, "Empty Message not allowed." if empty_message?
+      return :fail, "Empty message not allowed." if empty_message?
 
-      @errors = []
-      validate_pattern(commit_message_lines.join("\n"))
-      return :fail, @errors.join("\n") if @errors.any?
+      error_msg = validate_pattern(commit_message_lines.join("\n"))
+      return :fail, error_msg if error_msg
 
       :pass
     end
@@ -15,10 +14,12 @@ def run
 
     def validate_pattern(message)
       pattern = config['pattern']
-      expected_pattern_message = config['expected_pattern_message'] || ''
-      sample_message = config['sample_message'] || ''
       return if pattern.empty?
-      @errors << [
+
+      expected_pattern_message = config['expected_pattern_message']
+      sample_message = config['sample_message']
+
+      [
         'Commit message pattern mismatch.',
         "Expected : #{expected_pattern_message}",
         "Sample : #{sample_message}"

spec/overcommit/hook/commit_msg/msg_pattern_spec.rb spec/overcommit/hook/commit_msg/message_format_spec.rb

@@ -1,6 +1,6 @@
 require 'spec_helper'
 
-describe Overcommit::Hook::CommitMsg::MsgPattern do
+describe Overcommit::Hook::CommitMsg::MessageFormat do
   let(:config)  { Overcommit::ConfigurationLoader.default_configuration }
   let(:context) { double('context') }
   subject { described_class.new(config, context) }
@@ -20,23 +20,27 @@
     let(:config) do
       super().merge(Overcommit::Configuration.new(
         'CommitMsg' => {
-          'MsgPattern' => {
+          'MessageFormat' => {
             'pattern' => nil
           }
         }
       ))
     end
+
     let(:commit_msg) { 'Some Message' }
+
     it { should pass }
   end
 
   context 'when message does not match the pattern' do
     let(:commit_msg) { 'Some Message' }
+
     expected_message = [
       'Commit message pattern mismatch.',
       'Expected : <Issue Id> | <Commit Message Description> | <Developer(s)>',
       'Sample : DEFECT-1234 | Refactored Onboarding flow | John Doe'
     ].join("\n")
+
     it { should fail_hook expected_message }
   end
 end