Normalizer emulation (#9970)

Adds emulation for `java.text.Normalizer` using the native `normalize`
method on JavaScript's String.

user/super/com/google/gwt/emul/java/text/Normalizer.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2024 GWT Project Authors
+ *
+ * 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 java.text;
+
+import javaemul.internal.JsUtils;
+import jsinterop.annotations.JsType;
+
+/**
+ * Emulation of <a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/text/Normalizer.html">java.text.Normalizer</a>.
+ */
+public final class Normalizer {
+
+  public enum Form {
+    /** Canonical decomposition. */
+    NFD,
+    /** Canonical decomposition followed by composition. */
+    NFC,
+    /** Compatibility decomposition. */
+    NFKD,
+    /** Compatibility decomposition followed by composition. */
+    NFKC
+  }
+
+  public static String normalize(CharSequence input, Form form) {
+    return JsUtils.<NativeString>uncheckedCast(input.toString()).normalize(form.name());
+  }
+
+  public static boolean isNormalized(CharSequence input, Form form) {
+    String str = input.toString();
+    return str.equals(normalize(str, form));
+  }
+
+  @JsType(isNative = true, name = "String", namespace = "<window>")
+  private static class NativeString {
+    public native String normalize(String form);
+  }
+}
+

user/test/com/google/gwt/emultest/EmulSuite.java

@@ -58,6 +58,7 @@
 import com.google.gwt.emultest.java.sql.SqlDateTest;
 import com.google.gwt.emultest.java.sql.SqlTimeTest;
 import com.google.gwt.emultest.java.sql.SqlTimestampTest;
+import com.google.gwt.emultest.java.text.NormalizerTest;
 import com.google.gwt.emultest.java.util.ComparatorTest;
 import com.google.gwt.emultest.java.util.DateTest;
 import com.google.gwt.emultest.java.util.ObjectsTest;
@@ -135,6 +136,9 @@
   ObjectsTest.class,
   RandomTest.class,
 
+  // -- java.text
+  NormalizerTest.class,
+
   // Put last to reduce number of times the test framework switches modules
   MathContextWithObfuscatedEnumsTest.class,
 })

user/test/com/google/gwt/emultest/java/text/NormalizerTest.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2024 GWT Project Authors
+ *
+ * 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.google.gwt.emultest.java.text;
+
+import com.google.gwt.junit.client.GWTTestCase;
+
+import java.text.Normalizer;
+
+public class NormalizerTest extends GWTTestCase {
+
+  private String hangul = "\uD55C\uAE00";
+  private String hangulDecomposed = "\u1112\u1161\u11AB\u1100\u1173\u11AF";
+  private String ligatureFF = "\uFB00";
+
+  public void testNormalizeHangul() {
+    assertEquals(hangul, Normalizer.normalize(hangul, Normalizer.Form.NFC));
+    assertEquals(hangulDecomposed, Normalizer.normalize(hangul, Normalizer.Form.NFD));
+    assertEquals(hangul, Normalizer.normalize(hangul, Normalizer.Form.NFKC));
+    assertEquals(hangulDecomposed, Normalizer.normalize(hangul, Normalizer.Form.NFKD));
+    assertEquals(hangul, Normalizer.normalize(hangulDecomposed, Normalizer.Form.NFC));
+  }
+
+  public void testNormalizeLigature() {
+    assertEquals(ligatureFF, Normalizer.normalize(ligatureFF, Normalizer.Form.NFC));
+    assertEquals(ligatureFF, Normalizer.normalize(ligatureFF, Normalizer.Form.NFD));
+    assertEquals("ff", Normalizer.normalize(ligatureFF, Normalizer.Form.NFKC));
+    assertEquals("ff", Normalizer.normalize(ligatureFF, Normalizer.Form.NFKD));
+  }
+
+  public void testIsNormalizedHangul() {
+    assertTrue(Normalizer.isNormalized(hangul, Normalizer.Form.NFC));
+    assertFalse(Normalizer.isNormalized(hangul, Normalizer.Form.NFD));
+    assertTrue(Normalizer.isNormalized(hangul, Normalizer.Form.NFKC));
+    assertFalse(Normalizer.isNormalized(hangul, Normalizer.Form.NFKD));
+    assertFalse(Normalizer.isNormalized(hangulDecomposed, Normalizer.Form.NFC));
+  }
+
+  public void testIsNormalizedLigature() {
+    assertTrue(Normalizer.isNormalized(ligatureFF, Normalizer.Form.NFC));
+    assertTrue(Normalizer.isNormalized(ligatureFF, Normalizer.Form.NFD));
+    assertFalse(Normalizer.isNormalized(ligatureFF, Normalizer.Form.NFKC));
+    assertFalse(Normalizer.isNormalized(ligatureFF, Normalizer.Form.NFKD));
+  }
+
+  @Override
+  public String getModuleName() {
+    return "com.google.gwt.emultest.EmulSuite";
+  }
+}