skimage: report failure if expectation not found.

tools/skimage_main.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm_expectations.h"
 #include "SkBitmap.h"
 #include "SkBitmapHasher.h"
@@ skipping 184 matching lines @@
     if (NULL == filename || ++filename == '\0') {
         filename = fullPath;
     }
     return filename;
 }
 
 /**
  *  Compare against an expectation for this filename, if there is one.
  *  @param bitmap SkBitmap to compare to the expected value.
  *  @param filename String used to find the expected value.
- *  @return bool True if the bitmap matched the expectation, or if there was no expectation. False
- *      if there was an expecation that the bitmap did not match, or if an expectation could not be
- *      computed from an expectation.
+ *  @return bool True in any of these cases:
+ *                  - the bitmap matches the expectation.
+ *                  - there is no expectations file.
+ *               False in any of these cases:
+ *                  - there is an expectations file, but no expectation for this bitmap.
+ *                  - there is an expectation for this bitmap, but it did not match.
+ *                  - expectation could not be computed from the bitmap.
  */
 static bool compare_to_expectations_if_necessary(const SkBitmap& bitmap, const char* filename,
                                                  SkTArray<SkString, false>* failureArray) {
     if (NULL == gJsonExpectations.get()) {
         return true;
     }
 
     skiagm::Expectations jsExpectation = gJsonExpectations->get(filename);
     if (jsExpectation.empty()) {
-        return true;
+        if (failureArray != NULL) {
+            failureArray->push_back().printf("decoded %s, but could not find expectation.",
+                                             filename);
+        }
+        return false;
     }
 
     SkHashDigest checksum;
     if (!SkBitmapHasher::ComputeDigest(bitmap, &checksum)) {
         if (failureArray != NULL) {
             failureArray->push_back().printf("decoded %s, but could not create a checksum.",
                                              filename);
         }
         return false;
     }
@@ skipping 277 matching lines @@
     }
 
     return failed ? -1 : 0;
 }
 
 #if !defined SK_BUILD_FOR_IOS
 int main(int argc, char * const argv[]) {
     return tool_main(argc, (char**) argv);
 }
 #endif