godoc: changes to support aliases

Fixes golang.org/go#17763

Change-Id: I18012dcfd878db916cbb940c3a361a89341b9209
Reviewed-on: https://go-review.googlesource.com/32711
Reviewed-by: Robert Griesemer <gri@golang.org>

cmd/godoc/godoc_test.go

@@ -259,7 +259,7 @@ func testWeb(t *testing.T, withIndex bool) {
 			},
 		},
 		{
-			path: "/search?q=notwithstanding",
+			path: "/search?q=ListenAndServe",
 			match: []string{
 				"/src",
 			},

godoc/index18.go

@@ -542,6 +542,10 @@ func (x *Indexer) visitSpec(kind SpotKind, spec ast.Spec) {
 			}
 		}
 
+	case *ast.AliasSpec:
+		x.visitIdent(kind, n.Name)
+		ast.Walk(x, n.Orig)
+
 	case *ast.ValueSpec:
 		for _, n := range n.Names {
 			x.visitIdent(kind, n)

godoc/linkify18.go

@@ -158,6 +158,8 @@ func identModesFor(node ast.Node) map[*ast.Ident]identMode {
 			if name := n.Name; name != nil {
 				m[name] = identDef
 			}
+		case *ast.AliasSpec:
+			m[n.Name] = identVal
 		case *ast.ValueSpec:
 			for _, n := range n.Names {
 				m[n] = identVal

godoc/server18.go

@@ -427,6 +427,8 @@ func addNames(names map[string]bool, decl ast.Decl) {
 			switch s := spec.(type) {
 			case *ast.TypeSpec:
 				names[s.Name.Name] = true
+			case *ast.AliasSpec:
+				names[s.Name.Name] = true
 			case *ast.ValueSpec:
 				for _, id := range s.Names {
 					names[id.Name] = true

godoc/snippet18.go

@@ -42,6 +42,10 @@ func findSpec(list []ast.Spec, id *ast.Ident) ast.Spec {
 			if s.Name == id {
 				return s
 			}
+		case *ast.AliasSpec:
+			if s.Name == id {
+				return s
+			}
 		case *ast.ValueSpec:
 			for _, n := range s.Names {
 				if n == id {