Tests for getPrimaryHorizontal with grapheme boundaries

Bug: 25375561
Change-Id: I022473627499d7f18105e3a300754fae5be7da8e
diff --git a/core/tests/coretests/src/android/text/StaticLayoutTextMeasuringTest.java b/core/tests/coretests/src/android/text/StaticLayoutTextMeasuringTest.java
new file mode 100644
index 0000000..2e0e6dc
--- /dev/null
+++ b/core/tests/coretests/src/android/text/StaticLayoutTextMeasuringTest.java
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package android.text;
+
+import android.text.Layout.Alignment;
+import junit.framework.TestCase;
+
+/**
+ * Tests for text measuring methods of StaticLayout.
+ */
+public class StaticLayoutTextMeasuringTest extends TestCase {
+    private static final float SPACE_MULTI = 1.0f;
+    private static final float SPACE_ADD = 0.0f;
+    private static final int DEFAULT_OUTER_WIDTH = 150;
+    private static final Alignment DEFAULT_ALIGN = Alignment.ALIGN_LEFT;
+
+    private TextPaint mDefaultPaint;
+
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+        if (mDefaultPaint == null) {
+            mDefaultPaint = new TextPaint();
+        }
+    }
+
+    public void testGetPrimaryHorizontal_zwnbsp() {
+        // a, ZERO WIDTH NO-BREAK SPACE
+        String testString = "a\uFEFF";
+        StaticLayout layout = new StaticLayout(testString, mDefaultPaint,
+                DEFAULT_OUTER_WIDTH, DEFAULT_ALIGN, SPACE_MULTI, SPACE_ADD, true);
+
+        assertEquals(0.0f, layout.getPrimaryHorizontal(0));
+        assertEquals(layout.getPrimaryHorizontal(2), layout.getPrimaryHorizontal(1));
+    }
+
+    public void testGetPrimaryHorizontal_devanagari() {
+        // DEVANAGARI LETTER KA, DEVANAGARI VOWEL SIGN AA
+        String testString = "\u0915\u093E";
+        StaticLayout layout = new StaticLayout(testString, mDefaultPaint,
+                DEFAULT_OUTER_WIDTH, DEFAULT_ALIGN, SPACE_MULTI, SPACE_ADD, true);
+
+        assertEquals(0.0f, layout.getPrimaryHorizontal(0));
+        assertEquals(layout.getPrimaryHorizontal(2), layout.getPrimaryHorizontal(1));
+    }
+
+    public void testGetPrimaryHorizontal_flagEmoji() {
+        // REGIONAL INDICATOR SYMBOL LETTER U, REGIONAL INDICATOR SYMBOL LETTER S, REGIONAL
+        // INDICATOR SYMBOL LETTER Z
+        // First two code points (U and S) forms a US flag.
+        String testString = "\uD83C\uDDFA\uD83C\uDDF8\uD83C\uDDFF";
+        StaticLayout layout = new StaticLayout(testString, mDefaultPaint,
+                DEFAULT_OUTER_WIDTH, DEFAULT_ALIGN, SPACE_MULTI, SPACE_ADD, true);
+
+        assertEquals(0.0f, layout.getPrimaryHorizontal(0));
+        assertEquals(layout.getPrimaryHorizontal(4), layout.getPrimaryHorizontal(1));
+        assertEquals(layout.getPrimaryHorizontal(4), layout.getPrimaryHorizontal(2));
+        assertEquals(layout.getPrimaryHorizontal(4), layout.getPrimaryHorizontal(3));
+
+        assertTrue(layout.getPrimaryHorizontal(6) > layout.getPrimaryHorizontal(4));
+        assertEquals(layout.getPrimaryHorizontal(6), layout.getPrimaryHorizontal(5));
+    }
+}