1 files changed, 61 insertions, 0 deletions
diff --git a/Library/Homebrew/test/test_dependency_expansion.rb b/Library/Homebrew/test/test_dependency_expansion.rb
new file mode 100644
index 000000000..02a05dd1a
--- /dev/null
+++ b/Library/Homebrew/test/test_dependency_expansion.rb
@@ -0,0 +1,61 @@
+require 'testing_env'
+require 'dependency'
+
+class DependencyExpansionTests < Test::Unit::TestCase
+  def build_dep(name, deps=[])
+    dep = Dependency.new(name)
+    dep.stubs(:to_formula).returns(stub(:deps => deps))
+    dep
+  end
+
+  def setup
+    @foo = build_dep(:foo)
+    @bar = build_dep(:bar)
+    @baz = build_dep(:baz)
+    @qux = build_dep(:qux)
+    @deps = [@foo, @bar, @baz, @qux]
+    @f    = stub(:deps => @deps)
+  end
+
+  def test_expand_yields_dependent_and_dep_pairs
+    i = 0
+    Dependency.expand(@f) do |dependent, dep|
+      assert_equal @f, dependent
+      assert_equal dep, @deps[i]
+      i += 1
+    end
+  end
+
+  def test_expand_no_block
+    assert_equal @deps, Dependency.expand(@f)
+  end
+
+  def test_expand_prune_all
+    assert_empty Dependency.expand(@f) { Dependency.prune }
+  end
+
+  def test_expand_selective_pruning
+    deps = Dependency.expand(@f) do |_, dep|
+      Dependency.prune if dep.name == :foo
+    end
+
+    assert_equal [@bar, @baz, @qux], deps
+  end
+
+  def test_expand_preserves_dependency_order
+    @foo.stubs(:to_formula).returns(stub(:deps => [@qux, @baz]))
+    assert_equal [@qux, @baz, @foo, @bar], Dependency.expand(@f)
+  end
+
+  def test_expand_skips_optionals_by_default
+    @foo.expects(:optional?).returns(true)
+    @f = stub(:deps => @deps, :build => stub(:with? => false))
+    assert_equal [@bar, @baz, @qux], Dependency.expand(@f)
+  end
+
+  def test_expand_keeps_recommendeds_by_default
+    @foo.expects(:recommended?).returns(true)
+    @f = stub(:deps => @deps, :build => stub(:with? => true))
+    assert_equal @deps, Dependency.expand(@f)
+  end
+end