Merge "Extract getSuitableLocalesForSpellChecker()"

5 files changed, 287 insertions, 227 deletions

diff --git a/core/java/com/android/internal/inputmethod/InputMethodUtils.java b/core/java/com/android/internal/inputmethod/InputMethodUtils.java
index 1e5b5c80f31b..fe6706590abb 100644
--- a/core/java/com/android/internal/inputmethod/InputMethodUtils.java
+++ b/core/java/com/android/internal/inputmethod/InputMethodUtils.java
@@ -1320,133 +1320,6 @@ public class InputMethodUtils {
         }
     }
 
-    // For spell checker service manager.
-    // TODO: Should we have TextServicesUtils.java?
-    private static final Locale LOCALE_EN_US = new Locale("en", "US");
-    private static final Locale LOCALE_EN_GB = new Locale("en", "GB");
-
-    /**
-     * Returns a list of {@link Locale} in the order of appropriateness for the default spell
-     * checker service.
-     *
-     * <p>If the system language is English, and the region is also explicitly specified in the
-     * system locale, the following fallback order will be applied.</p>
-     * <ul>
-     * <li>(system-locale-language, system-locale-region, system-locale-variant) (if exists)</li>
-     * <li>(system-locale-language, system-locale-region)</li>
-     * <li>("en", "US")</li>
-     * <li>("en", "GB")</li>
-     * <li>("en")</li>
-     * </ul>
-     *
-     * <p>If the system language is English, but no region is specified in the system locale,
-     * the following fallback order will be applied.</p>
-     * <ul>
-     * <li>("en")</li>
-     * <li>("en", "US")</li>
-     * <li>("en", "GB")</li>
-     * </ul>
-     *
-     * <p>If the system language is not English, the following fallback order will be applied.</p>
-     * <ul>
-     * <li>(system-locale-language, system-locale-region, system-locale-variant) (if exists)</li>
-     * <li>(system-locale-language, system-locale-region) (if exists)</li>
-     * <li>(system-locale-language) (if exists)</li>
-     * <li>("en", "US")</li>
-     * <li>("en", "GB")</li>
-     * <li>("en")</li>
-     * </ul>
-     *
-     * @param systemLocale the current system locale to be taken into consideration.
-     * @return a list of {@link Locale}. The first one is considered to be most appropriate.
-     */
-    @VisibleForTesting
-    public static ArrayList<Locale> getSuitableLocalesForSpellChecker(
-            @Nullable final Locale systemLocale) {
-        final Locale systemLocaleLanguageCountryVariant;
-        final Locale systemLocaleLanguageCountry;
-        final Locale systemLocaleLanguage;
-        if (systemLocale != null) {
-            final String language = systemLocale.getLanguage();
-            final boolean hasLanguage = !TextUtils.isEmpty(language);
-            final String country = systemLocale.getCountry();
-            final boolean hasCountry = !TextUtils.isEmpty(country);
-            final String variant = systemLocale.getVariant();
-            final boolean hasVariant = !TextUtils.isEmpty(variant);
-            if (hasLanguage && hasCountry && hasVariant) {
-                systemLocaleLanguageCountryVariant = new Locale(language, country, variant);
-            } else {
-                systemLocaleLanguageCountryVariant = null;
-            }
-            if (hasLanguage && hasCountry) {
-                systemLocaleLanguageCountry = new Locale(language, country);
-            } else {
-                systemLocaleLanguageCountry = null;
-            }
-            if (hasLanguage) {
-                systemLocaleLanguage = new Locale(language);
-            } else {
-                systemLocaleLanguage = null;
-            }
-        } else {
-            systemLocaleLanguageCountryVariant = null;
-            systemLocaleLanguageCountry = null;
-            systemLocaleLanguage = null;
-        }
-
-        final ArrayList<Locale> locales = new ArrayList<>();
-        if (systemLocaleLanguageCountryVariant != null) {
-            locales.add(systemLocaleLanguageCountryVariant);
-        }
-
-        if (Locale.ENGLISH.equals(systemLocaleLanguage)) {
-            if (systemLocaleLanguageCountry != null) {
-                // If the system language is English, and the region is also explicitly specified,
-                // following fallback order will be applied.
-                // - systemLocaleLanguageCountry [if systemLocaleLanguageCountry is non-null]
-                // - en_US [if systemLocaleLanguageCountry is non-null and not en_US]
-                // - en_GB [if systemLocaleLanguageCountry is non-null and not en_GB]
-                // - en
-                if (systemLocaleLanguageCountry != null) {
-                    locales.add(systemLocaleLanguageCountry);
-                }
-                if (!LOCALE_EN_US.equals(systemLocaleLanguageCountry)) {
-                    locales.add(LOCALE_EN_US);
-                }
-                if (!LOCALE_EN_GB.equals(systemLocaleLanguageCountry)) {
-                    locales.add(LOCALE_EN_GB);
-                }
-                locales.add(Locale.ENGLISH);
-            } else {
-                // If the system language is English, but no region is specified, following
-                // fallback order will be applied.
-                // - en
-                // - en_US
-                // - en_GB
-                locales.add(Locale.ENGLISH);
-                locales.add(LOCALE_EN_US);
-                locales.add(LOCALE_EN_GB);
-            }
-        } else {
-            // If the system language is not English, the fallback order will be
-            // - systemLocaleLanguageCountry  [if non-null]
-            // - systemLocaleLanguage  [if non-null]
-            // - en_US
-            // - en_GB
-            // - en
-            if (systemLocaleLanguageCountry != null) {
-                locales.add(systemLocaleLanguageCountry);
-            }
-            if (systemLocaleLanguage != null) {
-                locales.add(systemLocaleLanguage);
-            }
-            locales.add(LOCALE_EN_US);
-            locales.add(LOCALE_EN_GB);
-            locales.add(Locale.ENGLISH);
-        }
-        return locales;
-    }
-
     public static boolean isSoftInputModeStateVisibleAllowed(
             int targetSdkVersion, int controlFlags) {
         if (targetSdkVersion < Build.VERSION_CODES.P) {
diff --git a/core/tests/coretests/src/com/android/internal/inputmethod/InputMethodUtilsTest.java b/core/tests/coretests/src/com/android/internal/inputmethod/InputMethodUtilsTest.java
index 3064afaeaab1..4dd5fcb5d2cc 100644
--- a/core/tests/coretests/src/com/android/internal/inputmethod/InputMethodUtilsTest.java
+++ b/core/tests/coretests/src/com/android/internal/inputmethod/InputMethodUtilsTest.java
@@ -71,15 +71,11 @@ public class InputMethodUtilsTest {
     private static final Locale LOCALE_FR = new Locale("fr");
     private static final Locale LOCALE_FR_CA = new Locale("fr", "CA");
     private static final Locale LOCALE_HI = new Locale("hi");
-    private static final Locale LOCALE_JA = new Locale("ja");
     private static final Locale LOCALE_JA_JP = new Locale("ja", "JP");
     private static final Locale LOCALE_ZH_CN = new Locale("zh", "CN");
     private static final Locale LOCALE_ZH_TW = new Locale("zh", "TW");
     private static final Locale LOCALE_IN = new Locale("in");
     private static final Locale LOCALE_ID = new Locale("id");
-    private static final Locale LOCALE_TH = new Locale("ht");
-    private static final Locale LOCALE_TH_TH = new Locale("ht", "TH");
-    private static final Locale LOCALE_TH_TH_TH = new Locale("ht", "TH", "TH");
     private static final String SUBTYPE_MODE_KEYBOARD = "keyboard";
     private static final String SUBTYPE_MODE_VOICE = "voice";
     private static final String SUBTYPE_MODE_HANDWRITING = "handwriting";
@@ -1087,101 +1083,6 @@ public class InputMethodUtilsTest {
     }
 
     @Test
-    public void testGetSuitableLocalesForSpellChecker() throws Exception {
-        {
-            final ArrayList<Locale> locales =
-                    InputMethodUtils.getSuitableLocalesForSpellChecker(LOCALE_EN_US);
-            assertEquals(3, locales.size());
-            assertEquals(LOCALE_EN_US, locales.get(0));
-            assertEquals(LOCALE_EN_GB, locales.get(1));
-            assertEquals(LOCALE_EN, locales.get(2));
-        }
-
-        {
-            final ArrayList<Locale> locales =
-                    InputMethodUtils.getSuitableLocalesForSpellChecker(LOCALE_EN_GB);
-            assertEquals(3, locales.size());
-            assertEquals(LOCALE_EN_GB, locales.get(0));
-            assertEquals(LOCALE_EN_US, locales.get(1));
-            assertEquals(LOCALE_EN, locales.get(2));
-        }
-
-        {
-            final ArrayList<Locale> locales =
-                    InputMethodUtils.getSuitableLocalesForSpellChecker(LOCALE_EN);
-            assertEquals(3, locales.size());
-            assertEquals(LOCALE_EN, locales.get(0));
-            assertEquals(LOCALE_EN_US, locales.get(1));
-            assertEquals(LOCALE_EN_GB, locales.get(2));
-        }
-
-        {
-            final ArrayList<Locale> locales =
-                    InputMethodUtils.getSuitableLocalesForSpellChecker(LOCALE_EN_IN);
-            assertEquals(4, locales.size());
-            assertEquals(LOCALE_EN_IN, locales.get(0));
-            assertEquals(LOCALE_EN_US, locales.get(1));
-            assertEquals(LOCALE_EN_GB, locales.get(2));
-            assertEquals(LOCALE_EN, locales.get(3));
-        }
-
-        {
-            final ArrayList<Locale> locales =
-                    InputMethodUtils.getSuitableLocalesForSpellChecker(LOCALE_JA_JP);
-            assertEquals(5, locales.size());
-            assertEquals(LOCALE_JA_JP, locales.get(0));
-            assertEquals(LOCALE_JA, locales.get(1));
-            assertEquals(LOCALE_EN_US, locales.get(2));
-            assertEquals(LOCALE_EN_GB, locales.get(3));
-            assertEquals(Locale.ENGLISH, locales.get(4));
-        }
-
-        // Test 3-letter language code.
-        {
-            final ArrayList<Locale> locales =
-                    InputMethodUtils.getSuitableLocalesForSpellChecker(LOCALE_FIL_PH);
-            assertEquals(5, locales.size());
-            assertEquals(LOCALE_FIL_PH, locales.get(0));
-            assertEquals(LOCALE_FIL, locales.get(1));
-            assertEquals(LOCALE_EN_US, locales.get(2));
-            assertEquals(LOCALE_EN_GB, locales.get(3));
-            assertEquals(Locale.ENGLISH, locales.get(4));
-        }
-
-        // Test variant.
-        {
-            final ArrayList<Locale> locales =
-                    InputMethodUtils.getSuitableLocalesForSpellChecker(LOCALE_TH_TH_TH);
-            assertEquals(6, locales.size());
-            assertEquals(LOCALE_TH_TH_TH, locales.get(0));
-            assertEquals(LOCALE_TH_TH, locales.get(1));
-            assertEquals(LOCALE_TH, locales.get(2));
-            assertEquals(LOCALE_EN_US, locales.get(3));
-            assertEquals(LOCALE_EN_GB, locales.get(4));
-            assertEquals(Locale.ENGLISH, locales.get(5));
-        }
-
-        // Test Locale extension.
-        {
-            final Locale localeWithoutVariant = LOCALE_JA_JP;
-            final Locale localeWithVariant = new Locale.Builder()
-                    .setLocale(LOCALE_JA_JP)
-                    .setExtension('x', "android")
-                    .build();
-            assertFalse(localeWithoutVariant.equals(localeWithVariant));
-
-            final ArrayList<Locale> locales =
-                    InputMethodUtils.getSuitableLocalesForSpellChecker(localeWithVariant);
-            assertEquals(5, locales.size());
-            assertEquals(LOCALE_JA_JP, locales.get(0));
-            assertEquals(LOCALE_JA, locales.get(1));
-            assertEquals(LOCALE_EN_US, locales.get(2));
-            assertEquals(LOCALE_EN_GB, locales.get(3));
-            assertEquals(Locale.ENGLISH, locales.get(4));
-        }
-    }
-
-    @Test
     public void testConstructLocaleFromString() throws Exception {
         assertEquals(new Locale("en"), InputMethodUtils.constructLocaleFromString("en"));
         assertEquals(new Locale("en", "US"), InputMethodUtils.constructLocaleFromString("en_US"));
diff --git a/services/core/java/com/android/server/textservices/LocaleUtils.java b/services/core/java/com/android/server/textservices/LocaleUtils.java
new file mode 100644
index 000000000000..89d8c1e96614
--- /dev/null
+++ b/services/core/java/com/android/server/textservices/LocaleUtils.java
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2018 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.server.textservices;
+
+import android.annotation.Nullable;
+import android.text.TextUtils;
+
+import java.util.ArrayList;
+import java.util.Locale;
+
+/**
+ * Provides {@code Locale} related utility methods for {@link TextServicesManagerService}.
+ * <p>This class is intentionally package-private.  Utility methods here are tightly coupled with
+ * implementation details in {@link TextServicesManagerService}.  Hence this class is not suitable
+ * for other components to directly use.</p>
+ */
+final class LocaleUtils {
+    /**
+     * Returns a list of {@link Locale} in the order of appropriateness for the default spell
+     * checker service.
+     *
+     * <p>If the system language is English, and the region is also explicitly specified in the
+     * system locale, the following fallback order will be applied.</p>
+     * <ul>
+     * <li>(system-locale-language, system-locale-region, system-locale-variant) (if exists)</li>
+     * <li>(system-locale-language, system-locale-region)</li>
+     * <li>("en", "US")</li>
+     * <li>("en", "GB")</li>
+     * <li>("en")</li>
+     * </ul>
+     *
+     * <p>If the system language is English, but no region is specified in the system locale,
+     * the following fallback order will be applied.</p>
+     * <ul>
+     * <li>("en")</li>
+     * <li>("en", "US")</li>
+     * <li>("en", "GB")</li>
+     * </ul>
+     *
+     * <p>If the system language is not English, the following fallback order will be applied.</p>
+     * <ul>
+     * <li>(system-locale-language, system-locale-region, system-locale-variant) (if exists)</li>
+     * <li>(system-locale-language, system-locale-region) (if exists)</li>
+     * <li>(system-locale-language) (if exists)</li>
+     * <li>("en", "US")</li>
+     * <li>("en", "GB")</li>
+     * <li>("en")</li>
+     * </ul>
+     *
+     * @param systemLocale the current system locale to be taken into consideration.
+     * @return a list of {@link Locale}. The first one is considered to be most appropriate.
+     */
+    public static ArrayList<Locale> getSuitableLocalesForSpellChecker(
+            @Nullable final Locale systemLocale) {
+        final Locale systemLocaleLanguageCountryVariant;
+        final Locale systemLocaleLanguageCountry;
+        final Locale systemLocaleLanguage;
+        if (systemLocale != null) {
+            final String language = systemLocale.getLanguage();
+            final boolean hasLanguage = !TextUtils.isEmpty(language);
+            final String country = systemLocale.getCountry();
+            final boolean hasCountry = !TextUtils.isEmpty(country);
+            final String variant = systemLocale.getVariant();
+            final boolean hasVariant = !TextUtils.isEmpty(variant);
+            if (hasLanguage && hasCountry && hasVariant) {
+                systemLocaleLanguageCountryVariant = new Locale(language, country, variant);
+            } else {
+                systemLocaleLanguageCountryVariant = null;
+            }
+            if (hasLanguage && hasCountry) {
+                systemLocaleLanguageCountry = new Locale(language, country);
+            } else {
+                systemLocaleLanguageCountry = null;
+            }
+            if (hasLanguage) {
+                systemLocaleLanguage = new Locale(language);
+            } else {
+                systemLocaleLanguage = null;
+            }
+        } else {
+            systemLocaleLanguageCountryVariant = null;
+            systemLocaleLanguageCountry = null;
+            systemLocaleLanguage = null;
+        }
+
+        final ArrayList<Locale> locales = new ArrayList<>();
+        if (systemLocaleLanguageCountryVariant != null) {
+            locales.add(systemLocaleLanguageCountryVariant);
+        }
+
+        if (Locale.ENGLISH.equals(systemLocaleLanguage)) {
+            if (systemLocaleLanguageCountry != null) {
+                // If the system language is English, and the region is also explicitly specified,
+                // following fallback order will be applied.
+                // - systemLocaleLanguageCountry [if systemLocaleLanguageCountry is non-null]
+                // - en_US [if systemLocaleLanguageCountry is non-null and not en_US]
+                // - en_GB [if systemLocaleLanguageCountry is non-null and not en_GB]
+                // - en
+                if (systemLocaleLanguageCountry != null) {
+                    locales.add(systemLocaleLanguageCountry);
+                }
+                if (!Locale.US.equals(systemLocaleLanguageCountry)) {
+                    locales.add(Locale.US);
+                }
+                if (!Locale.UK.equals(systemLocaleLanguageCountry)) {
+                    locales.add(Locale.UK);
+                }
+                locales.add(Locale.ENGLISH);
+            } else {
+                // If the system language is English, but no region is specified, following
+                // fallback order will be applied.
+                // - en
+                // - en_US
+                // - en_GB
+                locales.add(Locale.ENGLISH);
+                locales.add(Locale.US);
+                locales.add(Locale.UK);
+            }
+        } else {
+            // If the system language is not English, the fallback order will be
+            // - systemLocaleLanguageCountry  [if non-null]
+            // - systemLocaleLanguage  [if non-null]
+            // - en_US
+            // - en_GB
+            // - en
+            if (systemLocaleLanguageCountry != null) {
+                locales.add(systemLocaleLanguageCountry);
+            }
+            if (systemLocaleLanguage != null) {
+                locales.add(systemLocaleLanguage);
+            }
+            locales.add(Locale.US);
+            locales.add(Locale.UK);
+            locales.add(Locale.ENGLISH);
+        }
+        return locales;
+    }
+}
diff --git a/services/core/java/com/android/server/textservices/TextServicesManagerService.java b/services/core/java/com/android/server/textservices/TextServicesManagerService.java
index 5c420ea13601..e5166655d18c 100644
--- a/services/core/java/com/android/server/textservices/TextServicesManagerService.java
+++ b/services/core/java/com/android/server/textservices/TextServicesManagerService.java
@@ -461,7 +461,7 @@ public class TextServicesManagerService extends ITextServicesManager.Stub {
         // is pre-installed or not.
         final Locale systemLocal = mContext.getResources().getConfiguration().locale;
         final ArrayList<Locale> suitableLocales =
-                InputMethodUtils.getSuitableLocalesForSpellChecker(systemLocal);
+                LocaleUtils.getSuitableLocalesForSpellChecker(systemLocal);
         if (DBG) {
             Slog.w(TAG, "findAvailSystemSpellCheckerLocked suitableLocales="
                     + Arrays.toString(suitableLocales.toArray(new Locale[suitableLocales.size()])));
diff --git a/services/tests/servicestests/src/com/android/server/textservices/LocaleUtilsTest.java b/services/tests/servicestests/src/com/android/server/textservices/LocaleUtilsTest.java
new file mode 100644
index 000000000000..3766d24b93d0
--- /dev/null
+++ b/services/tests/servicestests/src/com/android/server/textservices/LocaleUtilsTest.java
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2018 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.server.textservices;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.Locale;
+
+public class LocaleUtilsTest {
+    private static final Locale LOCALE_EN = new Locale("en");
+    private static final Locale LOCALE_EN_US = new Locale("en", "US");
+    private static final Locale LOCALE_EN_GB = new Locale("en", "GB");
+    private static final Locale LOCALE_EN_IN = new Locale("en", "IN");
+    private static final Locale LOCALE_FIL = new Locale("fil");
+    private static final Locale LOCALE_FIL_PH = new Locale("fil", "PH");
+    private static final Locale LOCALE_JA = new Locale("ja");
+    private static final Locale LOCALE_JA_JP = new Locale("ja", "JP");
+    private static final Locale LOCALE_TH = new Locale("ht");
+    private static final Locale LOCALE_TH_TH = new Locale("ht", "TH");
+    private static final Locale LOCALE_TH_TH_TH = new Locale("ht", "TH", "TH");
+
+    @Test
+    public void testGetSuitableLocalesForSpellChecker() throws Exception {
+        {
+            final ArrayList<Locale> locales =
+                    LocaleUtils.getSuitableLocalesForSpellChecker(LOCALE_EN_US);
+            assertEquals(3, locales.size());
+            assertEquals(LOCALE_EN_US, locales.get(0));
+            assertEquals(LOCALE_EN_GB, locales.get(1));
+            assertEquals(LOCALE_EN, locales.get(2));
+        }
+
+        {
+            final ArrayList<Locale> locales =
+                    LocaleUtils.getSuitableLocalesForSpellChecker(LOCALE_EN_GB);
+            assertEquals(3, locales.size());
+            assertEquals(LOCALE_EN_GB, locales.get(0));
+            assertEquals(LOCALE_EN_US, locales.get(1));
+            assertEquals(LOCALE_EN, locales.get(2));
+        }
+
+        {
+            final ArrayList<Locale> locales =
+                    LocaleUtils.getSuitableLocalesForSpellChecker(LOCALE_EN);
+            assertEquals(3, locales.size());
+            assertEquals(LOCALE_EN, locales.get(0));
+            assertEquals(LOCALE_EN_US, locales.get(1));
+            assertEquals(LOCALE_EN_GB, locales.get(2));
+        }
+
+        {
+            final ArrayList<Locale> locales =
+                    LocaleUtils.getSuitableLocalesForSpellChecker(LOCALE_EN_IN);
+            assertEquals(4, locales.size());
+            assertEquals(LOCALE_EN_IN, locales.get(0));
+            assertEquals(LOCALE_EN_US, locales.get(1));
+            assertEquals(LOCALE_EN_GB, locales.get(2));
+            assertEquals(LOCALE_EN, locales.get(3));
+        }
+
+        {
+            final ArrayList<Locale> locales =
+                    LocaleUtils.getSuitableLocalesForSpellChecker(LOCALE_JA_JP);
+            assertEquals(5, locales.size());
+            assertEquals(LOCALE_JA_JP, locales.get(0));
+            assertEquals(LOCALE_JA, locales.get(1));
+            assertEquals(LOCALE_EN_US, locales.get(2));
+            assertEquals(LOCALE_EN_GB, locales.get(3));
+            assertEquals(Locale.ENGLISH, locales.get(4));
+        }
+
+        // Test 3-letter language code.
+        {
+            final ArrayList<Locale> locales =
+                    LocaleUtils.getSuitableLocalesForSpellChecker(LOCALE_FIL_PH);
+            assertEquals(5, locales.size());
+            assertEquals(LOCALE_FIL_PH, locales.get(0));
+            assertEquals(LOCALE_FIL, locales.get(1));
+            assertEquals(LOCALE_EN_US, locales.get(2));
+            assertEquals(LOCALE_EN_GB, locales.get(3));
+            assertEquals(Locale.ENGLISH, locales.get(4));
+        }
+
+        // Test variant.
+        {
+            final ArrayList<Locale> locales =
+                    LocaleUtils.getSuitableLocalesForSpellChecker(LOCALE_TH_TH_TH);
+            assertEquals(6, locales.size());
+            assertEquals(LOCALE_TH_TH_TH, locales.get(0));
+            assertEquals(LOCALE_TH_TH, locales.get(1));
+            assertEquals(LOCALE_TH, locales.get(2));
+            assertEquals(LOCALE_EN_US, locales.get(3));
+            assertEquals(LOCALE_EN_GB, locales.get(4));
+            assertEquals(Locale.ENGLISH, locales.get(5));
+        }
+
+        // Test Locale extension.
+        {
+            final Locale localeWithoutVariant = LOCALE_JA_JP;
+            final Locale localeWithVariant = new Locale.Builder()
+                    .setLocale(LOCALE_JA_JP)
+                    .setExtension('x', "android")
+                    .build();
+            assertFalse(localeWithoutVariant.equals(localeWithVariant));
+
+            final ArrayList<Locale> locales =
+                    LocaleUtils.getSuitableLocalesForSpellChecker(localeWithVariant);
+            assertEquals(5, locales.size());
+            assertEquals(LOCALE_JA_JP, locales.get(0));
+            assertEquals(LOCALE_JA, locales.get(1));
+            assertEquals(LOCALE_EN_US, locales.get(2));
+            assertEquals(LOCALE_EN_GB, locales.get(3));
+            assertEquals(Locale.ENGLISH, locales.get(4));
+        }
+    }
+}