Convert brew pin and brew unpin test to spec.

Library/Homebrew/test/cmd/pin_spec.rb

@@ -0,0 +1,13 @@
+describe "brew pin", :integration_test do
+  it "pins a Formula's version" do
+    setup_test_formula "testball"
+    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
+
+    shutup do
+      expect { brew "pin", "testball" }.to be_a_success
+      expect { brew "upgrade" }.to be_a_success
+    end
+
+    expect(HOMEBREW_CELLAR/"testball/0.1").not_to be_a_directory
+  end
+end

Library/Homebrew/test/cmd/unpin_spec.rb

@@ -0,0 +1,14 @@
+describe "brew unpin", :integration_test do
+  it "unpins a Formula's version" do
+    setup_test_formula "testball"
+    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
+
+    shutup do
+      expect { brew "pin", "testball" }.to be_a_success
+      expect { brew "unpin", "testball" }.to be_a_success
+      expect { brew "upgrade" }.to be_a_success
+    end
+
+    expect(HOMEBREW_CELLAR/"testball/0.1").to be_a_directory
+  end
+end

Library/Homebrew/test/pin_unpin_test.rb

@@ -1,18 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestPinUnpin < IntegrationCommandTestCase
-  def test_pin_unpin
-    setup_test_formula "testball"
-    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
-
-    cmd("pin", "testball")
-    cmd("upgrade")
-    refute((HOMEBREW_CELLAR/"testball/0.1").directory?,
-      "The latest version directory should NOT be created")
-
-    cmd("unpin", "testball")
-    cmd("upgrade")
-    assert((HOMEBREW_CELLAR/"testball/0.1").directory?,
-      "The latest version directory should be created")
-  end
-end