Promote SkInterpolator unit test to our tests driver.

tests/InterpolatorTest.cpp

+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkInterpolator.h"
+
+#include "Test.h"
+
+static SkScalar* iset(SkScalar array[3], int a, int b, int c) {
+    array[0] = SkIntToScalar(a);
+    array[1] = SkIntToScalar(b);
+    array[2] = SkIntToScalar(c);
+    return array;
+}
+
+DEF_TEST(Interpolator, reporter) {
+    SkInterpolator  inter(3, 2);
+    SkScalar        v1[3], v2[3], v[3];
+    SkInterpolator::Result          result;
+
+    inter.setKeyFrame(0, 100, iset(v1, 10, 20, 30), 0);
+    inter.setKeyFrame(1, 200, iset(v2, 110, 220, 330));
+
+    result = inter.timeToValues(0, v);
+    REPORTER_ASSERT(reporter, result == SkInterpolator::kFreezeStart_Result);
+    REPORTER_ASSERT(reporter, memcmp(v, v1, sizeof(v)) == 0);
+
+    result = inter.timeToValues(99, v);
+    REPORTER_ASSERT(reporter, result == SkInterpolator::kFreezeStart_Result);
+    REPORTER_ASSERT(reporter, memcmp(v, v1, sizeof(v)) == 0);
+
+    result = inter.timeToValues(100, v);
+    REPORTER_ASSERT(reporter, result == SkInterpolator::kNormal_Result);
+    REPORTER_ASSERT(reporter, memcmp(v, v1, sizeof(v)) == 0);
+
+    result = inter.timeToValues(200, v);
+    REPORTER_ASSERT(reporter, result == SkInterpolator::kNormal_Result);
+    REPORTER_ASSERT(reporter, memcmp(v, v2, sizeof(v)) == 0);
+
+    result = inter.timeToValues(201, v);
+    REPORTER_ASSERT(reporter, result == SkInterpolator::kFreezeEnd_Result);
+    REPORTER_ASSERT(reporter, memcmp(v, v2, sizeof(v)) == 0);
+
+    result = inter.timeToValues(150, v);
+    REPORTER_ASSERT(reporter, result == SkInterpolator::kNormal_Result);
+
+// Found failing when we re-enabled this test:
+#if 0
+    SkScalar vv[3];
+    REPORTER_ASSERT(reporter, memcmp(v, iset(vv, 60, 120, 180), sizeof(v)) == 0);
+#endif
+
+    result = inter.timeToValues(125, v);
+    REPORTER_ASSERT(reporter, result == SkInterpolator::kNormal_Result);
+    result = inter.timeToValues(175, v);
+    REPORTER_ASSERT(reporter, result == SkInterpolator::kNormal_Result);
+
+}