test_download_strategies: add git tests

Library/Homebrew/test/test_download_strategies.rb

@@ -60,6 +60,69 @@ class VCSDownloadStrategyTests < Homebrew::TestCase
   end
 end
 
+class GitDownloadStrategyTests < Homebrew::TestCase
+  include FileUtils
+
+  def setup
+    resource = ResourceDouble.new("https://github.com/homebrew/foo")
+    @commit_id = 1
+    @strategy = GitDownloadStrategy.new("baz", resource)
+    @cached_location = @strategy.cached_location
+    mkpath @cached_location
+    touch @cached_location/"README"
+  end
+
+  def teardown
+    rmtree @cached_location
+  end
+
+  def git_commit_all
+    shutup do
+      system "git", "add", "--all"
+      system "git", "commit", "-m", "commit number #{@commit_id}"
+      @commit_id += 1
+    end
+  end
+
+  def inside_repo_using_git_env
+    initial_env = ENV.to_hash
+    %w[AUTHOR COMMITTER].each do |role|
+      ENV["GIT_#{role}_NAME"] = "brew tests"
+      ENV["GIT_#{role}_EMAIL"] = "brew-tests@localhost"
+      ENV["GIT_#{role}_DATE"] = "Thu May 21 00:04:11 2009 +0100"
+    end
+    @cached_location.cd do
+      yield
+    end
+  ensure
+    ENV.replace(initial_env)
+  end
+
+  def setup_git_repo
+    inside_repo_using_git_env do
+      shutup do
+        system "git", "init"
+        system "git", "remote", "add", "origin", "https://github.com/Homebrew/homebrew-foo"
+      end
+      git_commit_all
+    end
+  end
+
+  def test_source_modified_time
+    setup_git_repo
+    assert_equal 1242860651, @strategy.source_modified_time.to_i
+  end
+
+  def test_last_commit
+    setup_git_repo
+    inside_repo_using_git_env do
+      touch "LICENSE"
+      git_commit_all
+    end
+    assert_equal "c50c79b", @strategy.last_commit
+  end
+end
+
 class DownloadStrategyDetectorTests < Homebrew::TestCase
   def setup
     @d = DownloadStrategyDetector.new