[annotee] add SOURCE_MANIFEST annotation.

logdog/client/annotee/annotation/annotation_test.go

 // Copyright 2015 The LUCI Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //      http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 127 matching lines @@
         path := filepath.Join(testDataDir, fmt.Sprintf("%s.annotations.txt", normalize(name)))
         f, err := os.Open(path)
         if err != nil {
                 t.Errorf("Failed to open annotations source [%s]: %v", path, err)
                 return "", err
         }
         defer f.Close()
 
         scanner := bufio.NewScanner(f)
         var nextErr string
-        for scanner.Scan() {
+        for lineNo := 1; scanner.Scan(); lineNo++ {
                 // Trim, discard empty lines and comment lines.
                 line := strings.TrimLeftFunc(scanner.Text(), unicode.IsSpace)
                 if len(line) == 0 || strings.HasPrefix(line, "#") {
                         continue
                 }
 
                 switch {
                 case line == "+time":
                         tc.Add(1 * time.Second)
 
                 case strings.HasPrefix(line, "+error"):
                         nextErr = strings.SplitN(line, " ", 2)[1]
 
                 default:
                         // Annotation.
                         err := st.Append(line)
                         if nextErr != "" {
                                 expectedErr := nextErr
                                 nextErr = ""
 
                                 if err == nil {
-                                        return "", fmt.Errorf("expected error, but didn't encounter it: %q", expectedErr)
+                                        return "", fmt.Errorf("line %d: expected error, but didn't encounter it: %q", lineNo, expectedErr)
                                 }
                                 if !strings.Contains(err.Error(), expectedErr) {
-                                        return "", fmt.Errorf("expected error %q, but got: %v", expectedErr, err)
+                                        return "", fmt.Errorf("line %d: expected error %q, but got: %v", lineNo, expectedErr, err)
                                 }
                         } else if err != nil {
                                 return "", err
                         }
                 }
         }
 
         return path, nil
 }
 
@@ skipping 164 matching lines @@
 
                 Convey(`Append to a closed State is a no-op.`, func() {
                         st := testCases[0].state(startTime)
                         st.Finish()
                         sclone := st
                         So(st.Append("asdf"), ShouldBeNil)
                         So(st, ShouldResemble, sclone)
                 })
         })
 }