Add command config option to hooks

One feature Overcommit is missing is the ability to execute a command
within a particular environment (e.g. `bundle exec` in Ruby or
`virtualenv` in Python).

In order to support this, add a `command` option which can be configured
in `.overcommit.yml`, and update all existing hooks to respect this
option. If not specified, it defaults to the required executable for the
hook.

Change-Id: Id705739021139babf963ba11a47691acb74e4804
Reviewed-on: http://gerrit.causes.com/46312
Tested-by: jenkins <jenkins@brigade.com>
Reviewed-by: Shane da Silva <shane.dasilva@brigade.com>

Author: sds

.overcommit.yml

@@ -5,3 +5,9 @@ CommitMsg:
 PreCommit:
   Reek:
     enabled: false
+
+  Rubocop:
+    command: ['bundle', 'exec', 'rubocop']
+
+  Travis:
+    command: ['bundle', 'exec', 'travis']

CHANGELOG.md

@@ -4,6 +4,8 @@
 
 * Disable `Reek` pre-commit hook by default
 * Allow `required_executable` to include paths that are in the repo root
+* Add `command` hook option allowing the actual command that is executed
+  to be configured (useful to invoke command via `bundle exec` or similar)
 
 ## 0.21.0
 

README.md

@@ -189,6 +189,11 @@ Within a configuration file, the following high-level concepts exist:
     a warning to either `pass` or `fail`
   * `required_executable`: Name of an executable that needs to exist in order
     for the hook to run
+  * `command`: Array of command line arguments to use as the command. How each
+    hook uses this is different, but it ultimately allows hooks to customize
+    how they are run so they can be invoked in a different context, for example
+    running `bundle exec rubocop` instead of just `rubocop` so you can use gem
+    versions specified in your local `Gemfile.lock`
   * `install_command`: Command the user can run to install the
     `required_executable`
 

lib/overcommit/hook/base.rb

@@ -111,10 +111,20 @@ def execute(cmd)
       Overcommit::Utils.execute(cmd)
     end
 
-    def executable
+    def required_executable
       @config['required_executable']
     end
 
+    # Return command to execute for this hook.
+    #
+    # This is intended to be configurable so hooks can prefix their commands
+    # with `bundle exec` or similar.
+    #
+    # @return [Array<String>]
+    def command
+      Array(@config['command'] || required_executable)
+    end
+
     # Gets a list of staged files that apply to this hook based on its
     # configured `include` and `exclude` lists.
     def applicable_files
@@ -146,9 +156,9 @@ def applicable_file?(file)
     # If the hook defines a required executable, check if it's in the path and
     # display the install command if one exists.
     def check_for_executable
-      return unless executable && !in_path?(executable)
+      return unless required_executable && !in_path?(required_executable)
 
-      output = "'#{executable}' is not installed (or is not in your PATH)"
+      output = "'#{required_executable}' is not installed (or is not in your PATH)"
 
       if install_command = @config['install_command']
         output += "\nInstall it by running: #{install_command}"

lib/overcommit/hook/pre_commit/berksfile_check.rb

@@ -9,7 +9,7 @@ def run
       ignored_files = execute(%w[git ls-files -o -i --exclude-standard]).stdout.split("\n")
       return :pass if ignored_files.include?(LOCK_FILE)
 
-      result = execute(%W[#{executable} list --quiet])
+      result = execute(command + %w[list --quiet])
       unless result.success?
         return :fail, result.stderr
       end

lib/overcommit/hook/pre_commit/brakeman.rb

@@ -2,8 +2,9 @@ module Overcommit::Hook::PreCommit
   # Runs `brakeman` against any modified Ruby/Rails files.
   class Brakeman < Base
     def run
-      result = execute(%W[#{executable} --exit-on-warn --quiet --summary --only-files] <<
-                       applicable_files.join(','))
+      result = execute(command +
+                       %w[--exit-on-warn --quiet --summary --only-files] +
+                       [applicable_files.join(',')])
       return :pass if result.success?
 
       [:fail, result.stdout]

lib/overcommit/hook/pre_commit/bundle_check.rb

@@ -9,14 +9,14 @@ def run
       ignored_files = execute(%w[git ls-files -o -i --exclude-standard]).stdout.split("\n")
       return :pass if ignored_files.include?(LOCK_FILE)
 
-      result = execute(%W[#{executable} check])
+      result = execute(command + ['check'])
       unless result.success?
         return :fail, result.stdout
       end
 
       result = execute(%w[git diff --quiet --] + [LOCK_FILE])
       unless result.success?
-        return :fail, "#{LOCK_FILE} is not up-to-date -- run `#{executable} check`"
+        return :fail, "#{LOCK_FILE} is not up-to-date -- run `#{command.join(' ')} check`"
       end
 
       :pass

lib/overcommit/hook/pre_commit/chamber_security.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `chamber secure` against any modified Chamber settings files
   class ChamberSecurity < Base
     def run
-      result = execute(%W[#{executable} secure --files] + applicable_files)
+      result = execute(command + %w[secure --files] + applicable_files)
 
       return :pass if result.stdout.empty?
       [:fail, "These settings appear to need to be secured but were not: #{result.stdout}"]

lib/overcommit/hook/pre_commit/coffee_lint.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `coffeelint` against any modified CoffeeScript files.
   class CoffeeLint < Base
     def run
-      result = execute(%W[#{executable} --quiet] + applicable_files)
+      result = execute(command + %w[--quiet] + applicable_files)
       return :pass if result.success?
 
       [:fail, result.stdout]

lib/overcommit/hook/pre_commit/css_lint.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `csslint` against any modified CSS files.
   class CssLint < Base
     def run
-      result = execute(%W[#{executable} --quiet --format=compact] + applicable_files)
+      result = execute(command + %w[--quiet --format=compact] + applicable_files)
       return :pass if result.stdout !~ /Error - (?!Unknown @ rule)/
 
       [:fail, result.stdout]

lib/overcommit/hook/pre_commit/go_lint.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `golint` against any modified Golang files.
   class GoLint < Base
     def run
-      result = execute([executable] + applicable_files)
+      result = execute(command + applicable_files)
       # Unfortunately the exit code is always 0
       return :pass if result.stdout.empty?
 

lib/overcommit/hook/pre_commit/haml_lint.rb

@@ -6,7 +6,7 @@ class HamlLint < Base
     end
 
     def run
-      result = execute([executable] + applicable_files)
+      result = execute(command + applicable_files)
       return :pass if result.success?
 
       extract_messages(

lib/overcommit/hook/pre_commit/js_hint.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `jshint` against any modified JavaScript files.
   class JsHint < Base
     def run
-      result = execute([executable] + applicable_files)
+      result = execute(command + applicable_files)
       output = result.stdout
 
       return :pass if output.empty?

lib/overcommit/hook/pre_commit/jscs.rb

@@ -3,7 +3,7 @@ module Overcommit::Hook::PreCommit
   # files.
   class Jscs < Base
     def run
-      result = execute(%W[#{executable} --reporter=inline --verbose] + applicable_files)
+      result = execute(command + %w[--reporter=inline --verbose] + applicable_files)
       return :pass if result.success?
 
       if result.status == 1

lib/overcommit/hook/pre_commit/jsx_hint.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `jsxhint` against any modified JSX files.
   class JsxHint < Base
     def run
-      result = execute([executable] + applicable_files)
+      result = execute(command + applicable_files)
       output = result.stdout
 
       return :pass if output.empty?

lib/overcommit/hook/pre_commit/jsxcs.rb

@@ -3,7 +3,7 @@ module Overcommit::Hook::PreCommit
   # against any modified JavaScript files.
   class Jsxcs < Base
     def run
-      result = execute(%W[#{executable} --reporter=inline] + applicable_files)
+      result = execute(command + %w[--reporter=inline] + applicable_files)
       return :pass if result.success?
 
       if result.status == 1

lib/overcommit/hook/pre_commit/python_flake8.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `flake8` against any modified Python files.
   class PythonFlake8 < Base
     def run
-      result = execute([executable] + applicable_files)
+      result = execute(command + applicable_files)
       return :pass if result.success?
 
       [:fail, result.stdout]

lib/overcommit/hook/pre_commit/reek.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `reek` against any modified Ruby files.
   class Reek < Base
     def run
-      result = execute(%W[#{executable} --single-line --no-color] + applicable_files)
+      result = execute(command + %w[--single-line --no-color] + applicable_files)
       return :pass if result.success?
 
       output = scrub_output(result.stdout + result.stderr)

lib/overcommit/hook/pre_commit/rubocop.rb

@@ -6,7 +6,7 @@ class Rubocop < Base
     end
 
     def run
-      result = execute(%W[#{executable} --format=emacs --force-exclusion] + applicable_files)
+      result = execute(command + %w[--format=emacs --force-exclusion] + applicable_files)
       return :pass if result.success?
 
       extract_messages(

lib/overcommit/hook/pre_commit/scss_lint.rb

@@ -6,7 +6,7 @@ class ScssLint < Base
     end
 
     def run
-      result = execute([executable] + applicable_files)
+      result = execute(command + applicable_files)
       return :pass if result.success?
 
       extract_messages(

lib/overcommit/hook/pre_commit/shell_check.rb

@@ -6,7 +6,7 @@ class ShellCheck < Base
     end
 
     def run
-      result = execute(%W[#{executable} --format=gcc] + applicable_files)
+      result = execute(command + %w[--format=gcc] + applicable_files)
       return :pass if result.success?
 
       extract_messages(

lib/overcommit/hook/pre_commit/travis_lint.rb

@@ -2,7 +2,7 @@ module Overcommit::Hook::PreCommit
   # Runs `travis-lint` against any modified Travis CI files.
   class TravisLint < Base
     def run
-      result = execute([executable, 'lint'] + applicable_files)
+      result = execute(command + %w[lint] + applicable_files)
       return :pass if result.success?
 
       [:fail, (result.stdout + result.stderr).strip]