Merge pull request #381 from bitglue/master

Don't conflate stdout and stderr; run commands once

Rakefile

@@ -6,16 +6,17 @@ task :spec => 'spec:all'
 
 namespace :spec do
   oses = %w( darwin debian gentoo plamo redhat aix solaris solaris10 solaris11 smartos windows freebsd freebsd10)
+  backends = %w( exec ssh cmd winrm powershell )
 
-  task :all => [ oses.map {|os| "spec:#{os}" }, :exec, :ssh, :cmd, :winrm, :powershell, :helper ].flatten
+  task :all => [ oses.map {|os| "spec:#{os}" }, backends, :helper, :unit ].flatten
 
   oses.each do |os|
     RSpec::Core::RakeTask.new(os.to_sym) do |t|
       t.pattern = "spec/#{os}/*_spec.rb"
     end
   end
 
-  [:exec, :ssh, :cmd, :winrm, :powershell].each do |backend|
+  backends.each do |backend|
     RSpec::Core::RakeTask.new(backend) do |t|
       t.pattern = "spec/backend/#{backend.to_s}/*_spec.rb"
     end
@@ -24,4 +25,8 @@ namespace :spec do
   RSpec::Core::RakeTask.new(:helper) do |t|
     t.pattern = "spec/helper/*_spec.rb"
   end
+
+  RSpec::Core::RakeTask.new(:unit) do |t|
+    t.pattern = "spec/unit/*_spec.rb"
+  end
 end

lib/serverspec/type/command.rb

@@ -1,43 +1,42 @@
 module Serverspec
   module Type
     class Command < Base
-      attr_accessor :result
-
       def return_stdout?(content)
-        ret = backend.run_command(@name)
         if content.instance_of?(Regexp)
-          ret.stdout =~ content
+          stdout =~ content
         else
-          ret.stdout.strip == content
+          stdout.strip == content
         end
       end
 
       def return_stderr?(content)
-        ret = backend.run_command(@name)
         if content.instance_of?(Regexp)
-          ret.stderr =~ content
+          stderr =~ content
         else
-          ret.stderr.strip == content
+          stderr.strip == content
         end
       end
 
       def return_exit_status?(status)
-        ret = backend.run_command(@name)
-        ret.exit_status.to_i == status
+        exit_status == status
       end
 
       def stdout
-        if @result.nil?
-          @result = backend.run_command(@name).stdout
-        end
-        @result
+        command_result.stdout
       end
 
       def stderr
-        if @result.nil?
-          @result = backend.run_command(@name).stderr
-        end
-        @result
+        command_result.stderr
+      end
+
+      def exit_status
+        command_result.exit_status.to_i
+      end
+
+      private
+
+      def command_result()
+	@command_result ||= backend.run_command(@name)
       end
     end
   end

spec/unit/command_spec.rb

@@ -0,0 +1,81 @@
+require 'spec_helper'
+
+describe Serverspec::Type::Command do
+  subject { command('echo banana') }
+
+  before :each do
+    allow(subject.backend).to receive(:run_command).and_return(
+        CommandResult.new({
+          :stdout      => "banana\n",
+          :stderr      => "split\n",
+          :exit_status => "42",         # Command should convert this to an integer
+        })
+    )
+  end
+
+  it 'has stdout' do
+    expect(subject.stdout).to be == "banana\n"
+  end
+
+  it 'has stderr' do
+    expect(subject.stderr).to be == "split\n"
+  end
+
+  it 'has exit_status' do
+    expect(subject.exit_status).to be == 42
+  end
+
+  it 'does not conflate stdout and stderr' do
+    expect(subject.stdout).to eq("banana\n")
+    expect(subject.stderr).to eq("split\n")
+  end
+
+  it 'runs the command lazily' do
+    expect(subject.backend).to receive(:run_command).exactly(0).times
+
+    # Not sending any messages to the subject.
+  end
+
+  it 'does not run the command more than once' do
+    expect(subject.backend).to receive(:run_command).once
+
+    # We can send all these messages, but the command is invoked only once.
+    subject.stdout
+    subject.stderr
+    subject.exit_status
+    subject.return_stdout? 'foo'
+    subject.return_stderr? 'foo'
+    subject.return_exit_status? 0
+  end
+
+  describe '#return_stdout?' do
+    it 'matches against a string, stripping whitespace' do
+      expect(subject.return_stdout? 'banana').to be_true
+      expect(subject.return_stdout? 'pancake').to be_false
+    end
+
+    it 'matches against a regex' do
+      expect(subject.return_stdout? /anan/).to be_true
+      expect(subject.return_stdout? /^anan/).to be_false
+    end
+  end
+
+  describe '#return_stderr?' do
+    it 'matches against a string, stripping whitespace' do
+      expect(subject.return_stderr? 'split').to be_true
+      expect(subject.return_stderr? 'pancake').to be_false
+    end
+
+    it 'matches against a regex' do
+      expect(subject.return_stderr? /pli/).to be_true
+      expect(subject.return_stderr? /^pli/).to be_false
+    end
+  end
+
+  describe '#return_stderr?' do
+    it 'matches against an integer' do
+      expect(subject.return_exit_status? 42).to be_true
+      expect(subject.return_exit_status? 43).to be_false
+    end
+  end
+end