1 files changed, 57 insertions, 0 deletions
diff --git a/src/pkg/go/doc/example.go b/src/pkg/go/doc/example.go
new file mode 100644
index 000000000..7c59bf9bd
--- /dev/null
+++ b/src/pkg/go/doc/example.go
@@ -0,0 +1,57 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Extract example functions from package ASTs.
+
+package doc
+
+import (
+	"go/ast"
+	"go/printer"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+type Example struct {
+	Name   string                 // name of the item being demonstrated
+	Body   *printer.CommentedNode // code
+	Output string                 // expected output
+}
+
+func Examples(pkg *ast.Package) []*Example {
+	var examples []*Example
+	for _, src := range pkg.Files {
+		for _, decl := range src.Decls {
+			f, ok := decl.(*ast.FuncDecl)
+			if !ok {
+				continue
+			}
+			name := f.Name.Name
+			if !isTest(name, "Example") {
+				continue
+			}
+			examples = append(examples, &Example{
+				Name:   name[len("Example"):],
+				Body:   &printer.CommentedNode{f.Body, src.Comments},
+				Output: f.Doc.Text(),
+			})
+		}
+	}
+	return examples
+}
+
+// isTest tells whether name looks like a test, example, or benchmark.
+// It is a Test (say) if there is a character after Test that is not a
+// lower-case letter. (We don't want Testiness.)
+func isTest(name, prefix string) bool {
+	if !strings.HasPrefix(name, prefix) {
+		return false
+	}
+	if len(name) == len(prefix) { // "Test" is ok
+		return true
+	}
+	rune, _ := utf8.DecodeRuneInString(name[len(prefix):])
+	return !unicode.IsLower(rune)
+}