Add dartanalyzer pre-commit hook (sds#739)

* Add dartanalyzer pre-commit hook

* Fix lint issues

* Add lint message type categorization for DartAnalyzer

Author: esensar

README.md

@@ -498,6 +498,7 @@ issue](https://github.com/sds/overcommit/issues/238) for more details.
 * [CoffeeLint](lib/overcommit/hook/pre_commit/coffee_lint.rb)
 * [Credo](lib/overcommit/hook/pre_commit/credo.rb)
 * [CssLint](lib/overcommit/hook/pre_commit/css_lint.rb)
+* [DartAnalyzer](lib/overcommit/hook/pre_commit/dart_analyzer.rb)
 * [Dogma](lib/overcommit/hook/pre_commit/dogma.rb)
 * [ErbLint](lib/overcommit/hook/pre_commit/erb_lint.rb)
 * [EsLint](lib/overcommit/hook/pre_commit/es_lint.rb)

config/default.yml

@@ -266,6 +266,14 @@ PreCommit:
     install_command: 'npm install -g csslint'
     include: '**/*.css'
 
+  DartAnalyzer:
+    enabled: false
+    description: 'Analyze with dartanalyzer'
+    required_executable: 'dartanalyzer'
+    flags: []
+    include:
+      - '**/*.dart'
+
   Dogma:
     enabled: false
     description: 'Analyze with dogma'

lib/overcommit/hook/pre_commit/dart_analyzer.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module Overcommit::Hook::PreCommit
+  # Runs `dartanalyzer` against modified Dart files.
+  # @see https://dart.dev/tools/dartanalyzer
+  class DartAnalyzer < Base
+    MESSAGE_REGEX = /(?<type>.*)•\ (?<message>[^•]+)•\ (?<file>[^:]+):(?<line>\d+):(\d+)\.*/
+
+    def run
+      result = execute(command, args: applicable_files)
+      return :pass if result.success?
+
+      extract_messages(
+        result.stdout.split("\n").grep(MESSAGE_REGEX),
+        MESSAGE_REGEX,
+        lambda do |type|
+          type.include?('error') ? :error : :warning
+        end
+      )
+    end
+  end
+end

spec/overcommit/hook/pre_commit/dart_analyzer_spec.rb

@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Overcommit::Hook::PreCommit::DartAnalyzer do
+  let(:config)  { Overcommit::ConfigurationLoader.default_configuration }
+  let(:context) { double('context') }
+  subject { described_class.new(config, context) }
+
+  before do
+    subject.stub(:applicable_files).and_return(%w[file1.dart file2.dart])
+  end
+
+  context 'when dartanalyzer exits successfully' do
+    before do
+      result = double('result')
+      result.stub(:success?).and_return(true)
+      subject.stub(:execute).and_return(result)
+    end
+
+    it { should pass }
+  end
+
+  context 'when dartanalyzer exits unsucessfully' do
+    let(:result) { double('result') }
+
+    before do
+      result.stub(:success?).and_return(false)
+      subject.stub(:execute).and_return(result)
+    end
+
+    context 'and it reports an error' do
+      before do
+        result.stub(:stdout).and_return([
+          'Analyzing file1.dart...',
+          'error • message_ommitted • lib/file1.dart:35:3 • rule',
+          'Analyzing file2.dart...',
+          'hint • message_ommitted • lib/file2.dart:100:13 • rule',
+          'info • message_ommitted • lib/file2.dart:113:16 • rule',
+          '3 lints found.'
+        ].join("\n"))
+      end
+
+      it { should fail_hook }
+    end
+  end
+end