go 1.2rc2 (devel)

Update documentation and don't check with go vet. That is now in
go.tools starting in go 1.2. Make a check that go is working by using
`go fmt` and running a smal go program.

Closes Homebrew/homebrew#23359.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Formula/go.rb

@@ -18,9 +18,9 @@ class Go < Formula
   option 'without-cgo', "Build without cgo"
 
   devel do
-    url 'https://go.googlecode.com/files/go1.2rc1.src.tar.gz'
-    version '1.2rc1'
-    sha1 '9f39106e06f552e9bf6d15d201c4663c051d4f89'
+    url 'https://go.googlecode.com/files/go1.2rc2.src.tar.gz'
+    version '1.2rc2'
+    sha1 '1fc3b39431551ffa69035ccffea18f4328dc2e8c'
   end
 
   if build.with? 'cgo' and not build.devel?
@@ -87,7 +87,8 @@ class Go < Formula
     bin.install_symlink Dir["#{libexec}/bin/*"]
   end
 
-  def caveats; <<-EOS.undent
+  def caveats
+    changelog = <<-EOS.undent
     The go get command no longer allows $GOROOT as
     the default destination in Go 1.1 when downloading package source.
     To use the go get command, a valid $GOPATH is now required.
@@ -97,6 +98,19 @@ class Go < Formula
 
     More information here: http://golang.org/doc/code.html#GOPATH
     EOS
+
+    if build.devel?
+      changelog += <<-EOS.undent
+
+      In go 1.2 go vet and go doc are now part of the go.tools sub repo.
+      see: http://tip.golang.org/doc/go1.2#go_tools_godoc
+
+      To get go vet and go doc run:
+        $ go get code.google.com/p/go.tools/cmd/godoc
+        $ go get code.google.com/p/go.tools/cmd/vet
+      EOS
+    end
+    return changelog
   end
 
   test do
@@ -109,9 +123,9 @@ class Go < Formula
         fmt.Println("Hello World")
     }
     EOS
-    # Run go vet check for no errors then run the program.
-    # This is a a bare minimum of go working as it uses vet, build, and run.
-    system "#{bin}/go", "vet", "hello.go"
+    # Run go fmt check for no errors then run the program.
+    # This is a a bare minimum of go working as it uses fmt, build, and run.
+    system "#{bin}/go", "fmt", "hello.go"
     assert_equal "Hello World\n", `#{bin}/go run hello.go`
   end
 end