Merge pull request #24 from Shopify/ruby-script-support

Add running on a Ruby script

README.md

@@ -9,7 +9,8 @@ This gem provides a sane way to use Valgrind's memcheck on your native extension
     1. [How does it work?](#how-does-it-work)
     1. [Limitations](#limitations)
 1. [Installation](#installation)
-1. [Setup](#setup)
+1. [Running a Ruby script](#running-a-ruby-script)
+1. [Setup for test suites](#setup-for-test-suites)
 1. [Configuration](#configuration)
 1. [Suppression files](#suppression-files)
 1. [License](#license)
@@ -48,7 +49,16 @@ Because of the aggressive heuristics used to filter out false positives, there a
 gem install ruby_memcheck
 ```
 
-## Setup
+## Running a Ruby script
+
+You can run a Ruby script under ruby_memcheck. This will report all memory leaks in all native extensions found in your Ruby script. Simply replace the `ruby` part of your command with `ruby_memcheck`. For example:
+
+```sh
+$ ruby_memcheck -e "puts 'Hello world'"
+Hello world
+```
+
+## Setup for test suites
 
 > **Note**
 > If you encounter errors from Valgrind that looks like this:
@@ -69,7 +79,7 @@ gem install ruby_memcheck
 > sudo make install
 > ```
 
-The easiest way to use this gem is to use it on your test suite (minitest or RSpec) using rake.
+You can use ruby_memcheck on your test suite (Minitest or RSpec) using rake.
 
 0. Install Valgrind.
 1. In your Rakefile, require this gem.

exe/ruby_memcheck

@@ -0,0 +1,9 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+$LOAD_PATH.unshift("#{__dir__}/../lib")
+
+require "ruby_memcheck"
+
+runner = RubyMemcheck::RubyRunner.new
+exit(runner.run(*ARGV))

lib/ruby_memcheck.rb

@@ -1,10 +1,13 @@
 # frozen_string_literal: true
 
+require "English"
+require "shellwords"
 require "tempfile"
 require "rake/testtask"
 
 require "ruby_memcheck/configuration"
 require "ruby_memcheck/frame"
+require "ruby_memcheck/ruby_runner"
 require "ruby_memcheck/stack"
 require "ruby_memcheck/test_task_reporter"
 require "ruby_memcheck/test_task"

lib/ruby_memcheck/ruby_runner.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+module RubyMemcheck
+  class RubyRunner
+    attr_reader :configuration
+    attr_reader :reporter
+
+    def initialize(*args)
+      @configuration =
+        if !args.empty? && args[0].is_a?(Configuration)
+          args.shift
+        else
+          RubyMemcheck.default_configuration
+        end
+    end
+
+    def run(*args, **options)
+      command = configuration.command(args.map { |a| Shellwords.escape(a) })
+
+      @reporter = TestTaskReporter.new(configuration)
+
+      @reporter.setup
+
+      system(command, options)
+      exit_code = $CHILD_STATUS.exitstatus
+
+      @reporter.report_valgrind_errors
+
+      exit_code
+    end
+  end
+end

test/ruby_memcheck/ruby_runner_test.rb

@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require "ruby_memcheck/shared_test_task_reporter_tests"
+
+module RubyMemcheck
+  class RubyRunnerTest < Minitest::Test
+    include SharedTestTaskReporterTests
+
+    def setup
+      @output_io = StringIO.new
+      build_configuration
+    end
+
+    private
+
+    def run_with_memcheck(code, raise_on_failure: true, spawn_opts: {})
+      script = Tempfile.new
+      script.write(<<~RUBY)
+        require "ruby_memcheck_c_test_one"
+        require "ruby_memcheck_c_test_two"
+        #{code}
+      RUBY
+      script.flush
+
+      exit_code = @test_task.run(
+        "-I#{File.join(__dir__, "ext")}",
+        script.path,
+        **spawn_opts,
+      )
+
+      if raise_on_failure && exit_code != 0
+        raise "Command failed with status (#{exit_code})"
+      end
+
+      exit_code == 0
+    end
+
+    def build_test_task
+      @test_task = RubyMemcheck::RubyRunner.new(@configuration)
+    end
+  end
+end