Add a compatibility utility class for TextInfo

This is a groundwork for enabling LocaleSpan support in spell
checker service. TextInfo#getCharSequence is supposed to be
available in API Level 21 and later. We need some abstraction
layer as usual.

BUG: 16029304
Change-Id: Iafbf2877db393dbd040295c21d429334e3a13a5f

1 files changed, 85 insertions, 0 deletions

diff --git a/tests/src/com/android/inputmethod/compat/TextInfoCompatUtilsTests.java b/tests/src/com/android/inputmethod/compat/TextInfoCompatUtilsTests.java
new file mode 100644
index 000000000..e71d77460
--- /dev/null
+++ b/tests/src/com/android/inputmethod/compat/TextInfoCompatUtilsTests.java
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2014 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 com.android.inputmethod.compat;
+
+import android.graphics.Typeface;
+import android.os.Parcel;
+import android.test.AndroidTestCase;
+import android.test.suitebuilder.annotation.SmallTest;
+import android.text.SpannableString;
+import android.text.Spanned;
+import android.text.TextUtils;
+import android.text.style.StyleSpan;
+import android.text.style.URLSpan;
+import android.view.textservice.TextInfo;
+
+import java.util.Arrays;
+
+@SmallTest
+public class TextInfoCompatUtilsTests extends AndroidTestCase {
+    final private static String TEST_TEXT = "0123456789";
+    final private static int TEST_COOKIE = 0x1234;
+    final private static int TEST_SEQUENCE_NUMBER = 0x4321;
+    final private static int TEST_CHAR_SEQUENCE_START = 1;
+    final private static int TEST_CHAR_SEQUENCE_END = 6;
+    final private static StyleSpan TEST_STYLE_SPAN = new StyleSpan(Typeface.BOLD);
+    final private static int TEST_STYLE_SPAN_START = 4;
+    final private static int TEST_STYLE_SPAN_END = 5;
+    final private static int TEST_STYLE_SPAN_FLAGS = Spanned.SPAN_EXCLUSIVE_INCLUSIVE;
+    final private static URLSpan TEST_URL_SPAN_URL = new URLSpan("http://example.com");
+    final private static int TEST_URL_SPAN_START = 3;
+    final private static int TEST_URL_SPAN_END = 7;
+    final private static int TEST_URL_SPAN_FLAGS = Spanned.SPAN_EXCLUSIVE_EXCLUSIVE;
+
+    public void testGetCharSequence() {
+        final SpannableString text = new SpannableString(TEST_TEXT);
+        text.setSpan(TEST_STYLE_SPAN, TEST_STYLE_SPAN_START, TEST_STYLE_SPAN_END,
+                TEST_STYLE_SPAN_FLAGS);
+        text.setSpan(TEST_URL_SPAN_URL, TEST_URL_SPAN_START, TEST_URL_SPAN_END,
+                TEST_URL_SPAN_FLAGS);
+
+        final TextInfo textInfo = TextInfoCompatUtils.newInstance(text,
+                TEST_CHAR_SEQUENCE_START, TEST_CHAR_SEQUENCE_END, TEST_COOKIE,
+                TEST_SEQUENCE_NUMBER);
+        final Spanned expectedSpanned = (Spanned) text.subSequence(TEST_CHAR_SEQUENCE_START,
+                TEST_CHAR_SEQUENCE_END);
+        final CharSequence actualCharSequence = TextInfoCompatUtils.getCharSequence(textInfo, null);
+
+        // This should be valid even if TextInfo#getCharSequence is not supported.
+        assertTrue(TextUtils.equals(expectedSpanned, actualCharSequence));
+
+        if (TextInfoCompatUtils.isCharSequenceSupported()) {
+            // This is valid only if TextInfo#getCharSequence is supported.
+            assertTrue("should be Spanned", actualCharSequence instanceof Spanned);
+            assertTrue(Arrays.equals(marshall(expectedSpanned), marshall(actualCharSequence)));
+        }
+    }
+
+    private static byte[] marshall(final CharSequence cahrSequence) {
+        Parcel parcel = null;
+        try {
+            parcel = Parcel.obtain();
+            TextUtils.writeToParcel(cahrSequence, parcel, 0);
+            return parcel.marshall();
+        } finally {
+            if (parcel != null) {
+                parcel.recycle();
+                parcel = null;
+            }
+        }
+    }
+}