cmd/godoc: delete -path flag

Fixes #3453.

R=golang-dev, gri, jeff, bradfitz
CC=golang-dev
https://golang.org/cl/6350086

src/cmd/godoc/doc.go

@@ -67,8 +67,6 @@ The flags are:
 	-maxresults=10000
 		maximum number of full text search results shown
 		(no full text index is built if maxresults <= 0)
-	-path=""
-		additional package directories (colon-separated)
 	-html
 		print HTML in command-line mode
 	-goroot=$GOROOT
@@ -88,20 +86,8 @@ The flags are:
 		zip file providing the file system to serve; disabled if empty
 
 By default, godoc looks at the packages it finds via $GOROOT and $GOPATH (if set).
-Additional directories may be specified via the -path flag which accepts a list
-of colon-separated paths; unrooted paths are relative to the current working
-directory. Each path is considered as an additional root for packages in order
-of appearance. The last (absolute) path element is the prefix for the package
-path. For instance, given the flag value:
-
-	path=".:/home/bar:/public"
-
-for a godoc started in /home/user/godoc, absolute paths are mapped to package paths
-as follows:
-
-	/home/user/godoc/x -> godoc/x
-	/home/bar/x        -> bar/x
-	/public/x          -> public/x
+This behavior can be altered by providing an alternative $GOROOT with the -goroot
+flag.
 
 When godoc runs as a web server and -index is set, a search index is maintained.
 The index is created at startup.

src/cmd/godoc/godoc.go

@@ -57,7 +57,6 @@ var (
 	// TODO(gri) consider the invariant that goroot always end in '/'
 	goroot  = flag.String("goroot", runtime.GOROOT(), "Go root directory")
 	testDir = flag.String("testdir", "", "Go root subdirectory - for testing only (faster startups)")
-	pkgPath = flag.String("path", "", "additional package directories (colon-separated)")
 
 	// layout control
 	tabwidth       = flag.Int("tabwidth", 4, "tab width")
@@ -83,16 +82,6 @@ var (
 )
 
 func initHandlers() {
-	// Add named directories in -path argument as
-	// subdirectories of src/pkg.
-	for _, p := range filepath.SplitList(*pkgPath) {
-		_, elem := filepath.Split(p)
-		if elem == "" {
-			log.Fatalf("invalid -path argument: %q has no final element", p)
-		}
-		fs.Bind("/src/pkg/"+elem, OS(p), "/", bindReplace)
-	}
-
 	fileServer = http.FileServer(&httpFS{fs})
 	cmdHandler = docServer{"/cmd/", "/src/cmd", false}
 	pkgHandler = docServer{"/pkg/", "/src/pkg", true}