code review 101410046: gofmt/main: Added removal of empty declaration groups

src/cmd/gofmt/simplify.go

Index: src/cmd/gofmt/simplify.go 
=================================================================== 
--- a/src/cmd/gofmt/simplify.go 
+++ b/src/cmd/gofmt/simplify.go 
@@ -117,5 +117,34 @@ 
	} 
	} 
 
+	// remove empty declarations such as "const ()", etc 
+	removeEmptyDeclGroups(f) 
+ 
	ast.Walk(&s, f) 
 } 
+ 
+func removeEmptyDeclGroups(f *ast.File) { 
+	i := 0 
+	for _, d := range f.Decls { 
+	if g, ok := d.(*ast.GenDecl); !ok || !isEmpty(f, g) { 
+	f.Decls[i] = d 
+	i++ 
+	} 
+	} 
+	f.Decls = f.Decls[:i] 
+} 
+ 
+func isEmpty(f *ast.File, g *ast.GenDecl) bool { 
+	if g.Doc != nil || g.Specs != nil { 
+	return false 
+	} 
+ 
+	for _, c := range f.Comments { 
+	// if there is a comment in the declaration, it is not considered empty 
+	if g.Pos() <= c.Pos() && c.End() <= g.End() { 
+	return false 
+	} 
+	} 
+ 
+	return true 
+}