diff --git a/tests/WArrayTest.cpp b/tests/WArrayTest.cpp
new file mode 100644
index 0000000..428ca5f
--- /dev/null
+++ b/tests/WArrayTest.cpp
@@ -0,0 +1,219 @@
+/*
+ * 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 "Test.h"
+
+// Include the implementation so we can make an appropriate template instance.
+#include "SkAdvancedTypefaceMetrics.cpp"
+
+using namespace skia_advanced_typeface_metrics_utils;
+
+namespace {
+
+// Negative values and zeros in a range plus trailing zeros.
+//                        0  1   2  3  4  5  6  7  8  9 10 11 12 13 14
+const int16_t data1[] = {-1, 0, -3, 4, 5, 6, 7, 0, 0, 0, 8, 0, 0, 0, 0};
+const char* expected1 = "0[-1 0 -3 4 5 6 7 0 0 0 8]";
+
+// Run with leading and trailing zeros.
+// Test rules: d         0  1  2    3    4    5    6    7    8    9 10 11
+const int16_t data2[] = {0, 0, 0, 100, 100, 100, 100, 100, 100, 100, 0, 0};
+const char* expected2 = "3 9 100";
+
+// Removing 0's from a range.
+// Test rules: a         0  1  2  3  4  5  6  7  8  9 10 11
+const int16_t data3[] = {1, 2, 0, 0, 0, 3, 4, 0, 0, 0, 0, 5};
+const char* expected3 = "0[1 2 0 0 0 3 4] 11[5]";
+
+// Removing 0's from a run/range and between runs.
+// Test rules: a, b      0  1  2  3  4  5  6  7  8  9 10 11 12 14 15
+const int16_t data4[] = {1, 0, 0, 0, 1, 2, 2, 2, 3, 0, 0, 0, 0, 3, 4};
+const char* expected4 = "0[1 0 0 0 1] 5 7 2 8[3] 13[3 4]";
+
+// Runs that starts outside a range.
+// Test rules: a, e      0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17
+const int16_t data5[] = {1, 1, 2, 3, 0, 0, 0, 0, 5, 5, 6, 7, 0, 0, 0, 0, 8, 0};
+const char* expected5 = "0 1 1 2[2 3] 8 9 5 10[6 7] 16[8]";
+
+// Zeros and runs that should be broken out.
+// Test rules: a, b, e   0  1  2  3  4  5  6  7  8  9 10 11 12 13
+const int16_t data6[] = {1, 0, 0, 0, 0, 1, 2, 3, 3, 4, 5, 5, 5, 6};
+const char* expected6 = "0[1] 5[1 2 3 3 4] 10 12 5 13[6]";
+
+// Don't cares that aren't enough to break out a run.
+// Test rules: c         0  1   2   3  4  5
+const int16_t data7[] = {1, 2, 10, 11, 2, 3};
+const char* expected7 = "0[1 2 10 11 2 3]";
+const uint32_t subset7[] = {0, 1, 4, 5};
+const char* expectedSubset7 = "0[1 2 0 0 2 3]";
+
+// Don't cares that are enough to break out a run.
+// Test rules: c         0  1   2   3  4   5  6
+const int16_t data8[] = {1, 2, 10, 11, 12, 2, 3};
+const char* expected8 = "0[1 2 10 11 12 2 3]";
+const uint32_t subset8[] = {0, 1, 5, 6};
+const char* expectedSubset8 = "0[1] 1 5 2 6[3]";
+
+// Leading don't cares.
+// Test rules: d         0  1   2  3  4
+const int16_t data9[] = {1, 1, 10, 2, 3};
+const char* expected9 = "0 1 1 2[10 2 3]";
+const uint32_t subset9[] = {0, 1, 3, 4};
+const char* expectedSubset9 = "0 1 1 3[2 3]";
+
+// Almost run of don't cares inside a range.
+// Test rules: c          0  1   2   3   4  5
+const int16_t data10[] = {1, 2, 10, 11, 12, 3};
+const char* expected10 = "0[1 2 10 11 12 3]";
+const uint32_t subset10[] = {0, 1, 5};
+const char* expectedSubset10 = "0[1 2 0 0 0 3]";
+
+// Run of don't cares inside a range.
+// Test rules: c          0  1   2   3   4   5  6
+const int16_t data11[] = {1, 2, 10, 11, 12, 13, 3};
+const char* expected11 = "0[1 2 10 11 12 13 3]";
+const uint32_t subset11[] = {0, 1, 6};
+const char* expectedSubset11 = "0[1 2] 6[3]";
+
+// Almost run within a range with leading don't cares.
+// Test rules: c          0   1   2  3   4   5  6
+const int16_t data12[] = {1, 10, 11, 2, 12, 13, 3};
+const char* expected12 = "0[1 10 11 2 12 13 3]";
+const uint32_t subset12[] = {0, 3, 6};
+const char* expectedSubset12 = "0[1 0 0 2 0 0 3]";
+
+// Run within a range with leading don't cares.
+// Test rules: c          0   1   2  3  4   5   6  7
+const int16_t data13[] = {1, 10, 11, 2, 2, 12, 13, 3};
+const char* expected13 = "0[1 10 11 2 2 12 13 3]";
+const uint32_t subset13[] = {0, 3, 4, 7};
+const char* expectedSubset13 = "0[1] 1 6 2 7[3]";
+
+// Enough don't cares to breakup something.
+// Test rules: a          0  1  2  3  4  5
+const int16_t data14[] = {1, 0, 0, 0, 0, 2};
+const char* expected14 = "0[1] 5[2]";
+const uint32_t subset14[] = {0, 5};
+const char* expectedSubset14 = "0[1] 5[2]";
+
+}
+
+static SkString stringify_advance_data(
+        SkAdvancedTypefaceMetrics::AdvanceMetric<int16_t>* data) {
+    SkString result;
+    bool leadingSpace = false;
+    while (data != NULL) {
+      if (leadingSpace) {
+        result.appendf(" ");
+      } else {
+        leadingSpace = true;
+      }
+      switch(data->fType) {
+        case SkAdvancedTypefaceMetrics::AdvanceMetric<int16_t>::kRun:
+          result.appendf("%d %d %d", data->fStartId, data->fEndId,
+              data->fAdvance[0]);
+          break;
+        case SkAdvancedTypefaceMetrics::AdvanceMetric<int16_t>::kRange:
+          result.appendf("%d[", data->fStartId);
+          for (int i = 0; i < data->fAdvance.count(); ++i) {
+            if (i > 0) {
+              result.appendf(" ");
+            }
+            result.appendf("%d", data->fAdvance[i]);
+          }
+          result.appendf("]");
+          break;
+        case SkAdvancedTypefaceMetrics::AdvanceMetric<int16_t>::kDefault:
+          result.appendf("<Default=%d>", data->fAdvance[0]);
+          break;
+      }
+      data = data->fNext.get();
+    }
+    return result;
+}
+
+class TestWData {
+  public:
+    TestWData(skiatest::Reporter* reporter,
+              const int16_t advances[],
+              int advanceLen,
+              const uint32_t subset[],
+              int subsetLen,
+              const char* expected)
+            : fAdvances(advances)
+            , fAdvancesLen(advanceLen)
+            , fSubset(subset)
+            , fSubsetLen(subsetLen)
+            , fExpected(expected) {
+        REPORTER_ASSERT(reporter, RunTest());
+    }
+
+  private:
+    const int16_t* fAdvances;
+    const int fAdvancesLen;
+    const uint32_t* fSubset;
+    const int fSubsetLen;
+    const char* fExpected;
+
+    static bool getAdvance(TestWData* testCase, int gId, int16_t* advance) {
+        if (gId >= 0 && gId < testCase->fAdvancesLen) {
+            *advance = testCase->fAdvances[gId];
+            return true;
+        }
+        return false;
+    }
+
+    bool RunTest() {
+        SkTScopedPtr<SkAdvancedTypefaceMetrics::AdvanceMetric<int16_t> > result;
+        result.reset(getAdvanceData(this, fAdvancesLen, fSubset, fSubsetLen,
+                                    getAdvance));
+
+        SkString stringResult = stringify_advance_data(result.get());
+        if (!stringResult.equals(fExpected)) {
+            printf("Expected: %s\n  Result: %s\n", fExpected,
+                   stringResult.c_str());
+            return false;
+        }
+        return true;
+    }
+};
+
+static void TestWArray(skiatest::Reporter* reporter) {
+    TestWData(reporter, data1, SK_ARRAY_COUNT(data1), NULL, 0, expected1);
+    TestWData(reporter, data2, SK_ARRAY_COUNT(data2), NULL, 0, expected2);
+    TestWData(reporter, data3, SK_ARRAY_COUNT(data3), NULL, 0, expected3);
+    TestWData(reporter, data4, SK_ARRAY_COUNT(data4), NULL, 0, expected4);
+    TestWData(reporter, data5, SK_ARRAY_COUNT(data5), NULL, 0, expected5);
+    TestWData(reporter, data6, SK_ARRAY_COUNT(data6), NULL, 0, expected6);
+    TestWData(reporter, data7, SK_ARRAY_COUNT(data7), NULL, 0, expected7);
+    TestWData(reporter, data7, SK_ARRAY_COUNT(data7), subset7,
+              SK_ARRAY_COUNT(subset7), expectedSubset7);
+    TestWData(reporter, data8, SK_ARRAY_COUNT(data8), NULL, 0, expected8);
+    TestWData(reporter, data8, SK_ARRAY_COUNT(data8), subset8,
+              SK_ARRAY_COUNT(subset8), expectedSubset8);
+    TestWData(reporter, data9, SK_ARRAY_COUNT(data9), NULL, 0, expected9);
+    TestWData(reporter, data9, SK_ARRAY_COUNT(data9), subset9,
+              SK_ARRAY_COUNT(subset9), expectedSubset9);
+    TestWData(reporter, data10, SK_ARRAY_COUNT(data10), NULL, 0, expected10);
+    TestWData(reporter, data10, SK_ARRAY_COUNT(data10), subset10,
+              SK_ARRAY_COUNT(subset10), expectedSubset10);
+    TestWData(reporter, data11, SK_ARRAY_COUNT(data11), NULL, 0, expected11);
+    TestWData(reporter, data11, SK_ARRAY_COUNT(data11), subset11,
+              SK_ARRAY_COUNT(subset11), expectedSubset11);
+    TestWData(reporter, data12, SK_ARRAY_COUNT(data12), NULL, 0, expected12);
+    TestWData(reporter, data12, SK_ARRAY_COUNT(data12), subset12,
+              SK_ARRAY_COUNT(subset12), expectedSubset12);
+    TestWData(reporter, data13, SK_ARRAY_COUNT(data13), NULL, 0, expected13);
+    TestWData(reporter, data13, SK_ARRAY_COUNT(data13), subset13,
+              SK_ARRAY_COUNT(subset13), expectedSubset13);
+    TestWData(reporter, data14, SK_ARRAY_COUNT(data14), NULL, 0, expected14);
+    TestWData(reporter, data14, SK_ARRAY_COUNT(data14), subset14,
+              SK_ARRAY_COUNT(subset14), expectedSubset14);
+}
+
+#include "TestClassDef.h"
+DEFINE_TESTCLASS("WArray", WArrayTest, TestWArray)