SkTextBlob: Begin implementing Extended TextBlob API

tests/ExtendedTextBlob.cpp

+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "Test.h"
+#include "SkTextBlob.h"
+
+#include "SkTextBlobRunIterator.h"
+
+DEF_TEST(ExtendedTextBlob, reporter) {

[f(malita), 2016/06/27 20:21:56]

This could be added to TextBlobTest.cpp instead of new file.

[hal.canary, 2016/06/28 15:39:13]

Done.

+    SkTextBlobBuilder textBlobBuilder;
+    SkPaint paint;
+    const char text1[] = "Foo";
+    const char text2[] = "Bar";
+
+    int glyphCount = paint.textToGlyphs(text1, strlen(text1), nullptr);
+    SkAutoTMalloc<uint16_t> glyphs(glyphCount);
+    (void)paint.textToGlyphs(text1, strlen(text1), glyphs.get());
+    paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
+
+    auto run = textBlobBuilder.allocRunText(
+            paint, glyphCount, 0, 0, strlen(text2), SkString(), nullptr);
+    memcpy(run.glyphs, glyphs.get(), sizeof(uint16_t) * glyphCount);
+    memcpy(run.utf8text, text2, strlen(text2));
+    for (int i = 0; i < glyphCount; ++i) {
+        run.clusters[i] = SkTMin<uint32_t>(i, strlen(text2));
+    }
+    sk_sp<const SkTextBlob> blob(textBlobBuilder.build());
+    REPORTER_ASSERT(reporter, blob);
+
+    for (SkTextBlobRunIterator it(blob.get()); !it.done(); it.next()) {
+        REPORTER_ASSERT(reporter, it.glyphCount() == (uint32_t)glyphCount);
+        for (uint32_t i = 0; i < it.glyphCount(); ++i) {
+            REPORTER_ASSERT(reporter, it.glyphs()[i] == glyphs[i]);
+        }
+        REPORTER_ASSERT(reporter, SkTextBlob::kDefault_Positioning == it.positioning());
+        REPORTER_ASSERT(reporter, (SkPoint{0.0f, 0.0f}) == it.offset());
+        REPORTER_ASSERT(reporter, it.isExtended());
+        REPORTER_ASSERT(reporter, it.clusterBuffer());
+        for (uint32_t i = 0; i < it.glyphCount(); ++i) {
+            REPORTER_ASSERT(reporter, i == it.clusterBuffer()[i]);
+        }
+        REPORTER_ASSERT(reporter, 0 == strncmp(text2, it.textBuffer(), it.textSize()));
+    }
+}