gm: change ErrorBitfield to ErrorType/ErrorCombination
This will enable future GM changes to report errors more completely/consistently, like skdiff.
Review URL: https://codereview.chromium.org/12992003
git-svn-id: http://skia.googlecode.com/svn/trunk@8344 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gm/gm_error.h b/gm/gm_error.h
new file mode 100644
index 0000000..e0dbf1c
--- /dev/null
+++ b/gm/gm_error.h
@@ -0,0 +1,89 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/*
+ * Error codes used by gmmain.cpp.
+ */
+
+namespace skiagm {
+
+ /**
+ * The complete list of error types we might encounter in GM.
+ */
+ enum ErrorType {
+#if SK_SUPPORT_GPU
+ kNoGpuContext_ErrorType,
+#endif
+ kImageMismatch_ErrorType,
+ kMissingExpectations_ErrorType,
+ kWritingReferenceImage_ErrorType,
+ kLast_ErrorType = kWritingReferenceImage_ErrorType
+ };
+
+ /**
+ * A combination of 0 or more ErrorTypes.
+ */
+ class ErrorCombination {
+ public:
+ ErrorCombination() : fBitfield(0) {}
+ ErrorCombination(const ErrorType type) : fBitfield(1 << type) {}
+
+ /**
+ * Returns true iff there are NO errors.
+ */
+ bool isEmpty() const {
+ return (0 == this->fBitfield);
+ }
+
+ /**
+ * Adds this ErrorType to this ErrorCombination.
+ */
+ void add(const ErrorType type) {
+ this->fBitfield |= (1 << type);
+ }
+
+ /**
+ * Adds all ErrorTypes in "other" to this ErrorCombination.
+ */
+ void add(const ErrorCombination other) {
+ this->fBitfield |= other.fBitfield;
+ }
+
+ /**
+ * Returns true iff this ErrorCombination includes this ErrorType.
+ */
+ bool includes(const ErrorType type) const {
+ return !(0 == (this->fBitfield & (1 << type)));
+ }
+
+ /**
+ * Returns a new ErrorCombination, which includes the union of all
+ * ErrorTypes in two ErrorCombination objects (this and other).
+ */
+ ErrorCombination plus(const ErrorCombination& other) const {
+ ErrorCombination retval;
+ retval.fBitfield = this->fBitfield | other.fBitfield;
+ return retval;
+ }
+
+ /**
+ * Returns a new ErrorCombination, which is a copy of "this"
+ * but with all ErrorTypes in "other" removed.
+ */
+ ErrorCombination minus(const ErrorCombination& other) const {
+ ErrorCombination retval;
+ retval.fBitfield = this->fBitfield & ~(other.fBitfield);
+ return retval;
+ }
+
+ private:
+ int fBitfield;
+ };
+
+ // No errors at all.
+ const static ErrorCombination kEmpty_ErrorCombination;
+}