Prepare for initial J2KT support in common.hash.

android/guava-tests/test/com/google/common/hash/AbstractByteHasherTest.java

@@ -18,6 +18,7 @@
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertThrows;
 
+import com.google.common.annotations.J2ktIncompatible;
 import java.io.ByteArrayOutputStream;
 import java.util.Random;
 import junit.framework.TestCase;
@@ -66,6 +67,7 @@ public void testChar() {
     hasher.assertBytes(new byte[] {1, 2});
   }
 
+  @J2ktIncompatible // no UTF_16LE support
   public void testString() {
     Random random = new Random();
     for (int i = 0; i < 100; i++) {

android/guava-tests/test/com/google/common/hash/AbstractNonStreamingHashFunctionTest.java

@@ -16,6 +16,7 @@
 
 package com.google.common.hash;
 
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.collect.ImmutableList;
 import com.google.common.hash.HashTestUtils.RandomHasherAction;
 import java.io.ByteArrayOutputStream;
@@ -34,6 +35,7 @@ public class AbstractNonStreamingHashFunctionTest extends TestCase {
    * and checks that their results are identical, no matter which newHasher version we used.
    */
   public void testExhaustive() {
+    // TODO: b/484953702 - Split test so we can avoid StreamingVersion under J2KT.
     List<Hasher> hashers =
         ImmutableList.of(
             new StreamingVersion().newHasher(),
@@ -93,6 +95,7 @@ private static void assertPutString(char[] chars) {
     assertEquals(h1.hash(), h2.hash());
   }
 
+  @J2ktIncompatible // AbstractStreamingHasher
   static class StreamingVersion extends AbstractHashFunction {
     @Override
     public int bits() {

android/guava-tests/test/com/google/common/hash/AbstractStreamingHasherTest.java

@@ -21,6 +21,7 @@
 import static java.util.Collections.singleton;
 import static org.junit.Assert.assertThrows;
 
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.collect.Iterables;
 import com.google.common.hash.HashTestUtils.RandomHasherAction;
 import java.io.ByteArrayOutputStream;
@@ -38,6 +39,9 @@
  *
  * @author Dimitris Andreou
  */
+// All tests use Sink, which uses the currently J2KT-incompatible AbstractStreamingHasher
+// (Plus, testString in particular requires UTF_16LE support.)
+@J2ktIncompatible
 @NullUnmarked
 public class AbstractStreamingHasherTest extends TestCase {
   public void testBytes() {

android/guava-tests/test/com/google/common/hash/BloomFilterTest.java

@@ -29,6 +29,7 @@
 import static java.util.concurrent.TimeUnit.SECONDS;
 import static org.junit.Assert.assertThrows;
 
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.base.Stopwatch;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.hash.BloomFilterStrategies.LockFreeBitArray;
@@ -54,6 +55,7 @@
  * @author Dimitris Andreou
  */
 @NullUnmarked
+@J2ktIncompatible
 public class BloomFilterTest extends TestCase {
   private static final int NUM_PUTS = 100_000;
   private static final ThreadLocal<Random> random =

android/guava-tests/test/com/google/common/hash/ChecksumHashFunctionTest.java

@@ -18,6 +18,7 @@
 import static com.google.common.hash.Hashing.ChecksumType.CRC_32;
 import static com.google.common.truth.Truth.assertThat;
 
+import com.google.common.annotations.J2ktIncompatible;
 import java.util.zip.Checksum;
 import junit.framework.TestCase;
 import org.jspecify.annotations.NullUnmarked;
@@ -28,6 +29,7 @@
  * @author Colin Decker
  */
 @NullUnmarked
+@J2ktIncompatible
 public class ChecksumHashFunctionTest extends TestCase {
 
   public void testCrc32_equalsChecksumValue() throws Exception {

android/guava-tests/test/com/google/common/hash/Crc32cHashFunctionTest.java

@@ -17,6 +17,7 @@
 import static com.google.common.hash.Hashing.crc32c;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
+import com.google.common.annotations.J2ktIncompatible;
 import java.util.Arrays;
 import java.util.Random;
 import junit.framework.TestCase;
@@ -29,6 +30,7 @@
  * @author Kurt Alfred Kluever
  */
 @NullUnmarked
+@J2ktIncompatible
 public class Crc32cHashFunctionTest extends TestCase {
   public void testEmpty() {
     assertCrc(0, new byte[0]);

android/guava-tests/test/com/google/common/hash/Fingerprint2011Test.java

@@ -8,6 +8,7 @@
 import static java.nio.charset.StandardCharsets.UTF_8;
 import static java.util.Arrays.asList;
 
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableSortedMap;
 import com.google.common.collect.Ordering;
@@ -21,6 +22,7 @@
  * @author kylemaddison@google.com (Kyle Maddison)
  */
 @NullUnmarked
+@J2ktIncompatible
 public class Fingerprint2011Test extends TestCase {
 
   // Length of the sample string to produce

android/guava-tests/test/com/google/common/hash/FunnelsTest.java

@@ -32,6 +32,7 @@
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
 
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.testing.EqualsTester;
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
@@ -45,6 +46,7 @@
  *
  * @author Dimitris Andreou
  */
+@J2ktIncompatible
 @NullUnmarked
 public class FunnelsTest extends TestCase {
   public void testForBytes() {

android/guava-tests/test/com/google/common/hash/HashCodeTest.java

@@ -16,12 +16,13 @@
 
 package com.google.common.hash;
 
-import static com.google.common.hash.Hashing.sha1;
+import static com.google.common.hash.Hashing.farmHashFingerprint64;
 import static com.google.common.io.BaseEncoding.base16;
 import static com.google.common.truth.Truth.assertThat;
 import static java.nio.charset.StandardCharsets.US_ASCII;
 import static org.junit.Assert.assertThrows;
 
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.collect.ImmutableList;
 import com.google.common.io.BaseEncoding;
 import com.google.common.testing.ClassSanityTester;
@@ -178,16 +179,18 @@ public void testToString() {
     assertThat(base16().lowerCase().encode(data)).isEqualTo("7f8005ff0e");
   }
 
+  @J2ktIncompatible // ClassSanityTester
   public void testHashCode_nulls() throws Exception {
     sanityTester().testNulls();
   }
 
+  @J2ktIncompatible // ClassSanityTester
   public void testHashCode_equalsAndSerializable() throws Exception {
     sanityTester().testEqualsAndSerializable();
   }
 
   public void testRoundTripHashCodeUsingBaseEncoding() {
-    HashCode hash1 = sha1().hashString("foo", US_ASCII);
+    HashCode hash1 = farmHashFingerprint64().hashString("foo", US_ASCII);
     HashCode hash2 = HashCode.fromBytes(BaseEncoding.base16().lowerCase().decode(hash1.toString()));
     assertEquals(hash1, hash2);
   }
@@ -219,7 +222,7 @@ public void testObjectHashCodeWithSameLowOrderBytes() {
   }
 
   public void testRoundTripHashCodeUsingFromString() {
-    HashCode hash1 = sha1().hashString("foo", US_ASCII);
+    HashCode hash1 = farmHashFingerprint64().hashString("foo", US_ASCII);
     HashCode hash2 = HashCode.fromString(hash1.toString());
     assertEquals(hash1, hash2);
   }
@@ -238,7 +241,7 @@ public void testFromStringFailsWithInvalidHexChar() {
   }
 
   public void testFromStringFailsWithUpperCaseString() {
-    String string = sha1().hashString("foo", US_ASCII).toString().toUpperCase();
+    String string = farmHashFingerprint64().hashString("foo", US_ASCII).toString().toUpperCase();
     assertThrows(IllegalArgumentException.class, () -> HashCode.fromString(string));
   }
 
@@ -310,6 +313,7 @@ public void testWriteBytesToUndersizedArrayShortMaxLength() {
     assertThat(dest).isEqualTo(new byte[] {(byte) 0xaa, (byte) 0xbb, (byte) 0x00});
   }
 
+  @J2ktIncompatible // ClassSanityTester
   private static ClassSanityTester.FactoryMethodReturnValueTester sanityTester() {
     return new ClassSanityTester()
         .setDefault(byte[].class, new byte[] {1, 2, 3, 4})
@@ -357,7 +361,7 @@ private static void assertReadableBytes(HashCode hashCode) {
   private static class ExpectedHashCode {
     final byte[] bytes;
     final int asInt;
-    final Long asLong; // null means that asLong should throw an exception
+    final @Nullable Long asLong; // null means that asLong should throw an exception
     final String toString;
 
     ExpectedHashCode(byte[] bytes, int asInt, @Nullable Long asLong, String toString) {

android/guava-tests/test/com/google/common/hash/HashFunctionEnum.java

@@ -30,6 +30,7 @@
 import static com.google.common.hash.Hashing.sha512;
 import static com.google.common.hash.Hashing.sipHash24;
 
+import com.google.common.annotations.J2ktIncompatible;
 import org.jspecify.annotations.NullUnmarked;
 
 /**
@@ -39,6 +40,7 @@
  */
 @SuppressWarnings("deprecation") // We still need to test our deprecated APIs.
 @NullUnmarked
+@J2ktIncompatible
 enum HashFunctionEnum {
   ADLER32(adler32()),
   CRC32(crc32()),

android/guava-tests/test/com/google/common/hash/HashTestUtils.java

@@ -636,6 +636,7 @@ private static void assertHashLongEquivalence(HashFunction hashFunction, Random
     assertEquals(hashFunction.hashLong(l), hashFunction.newHasher().putLong(l).hash());
   }
 
+  // TODO: b/484953702 - Put a list in TestPlatform so that J2KT can omit some of these.
   private static final ImmutableSet<Charset> CHARSETS =
       ImmutableSet.of(ISO_8859_1, US_ASCII, UTF_16, UTF_16BE, UTF_16LE, UTF_8);
 

android/guava-tests/test/com/google/common/hash/HashingInputStreamTest.java

@@ -21,6 +21,7 @@
 import static org.mockito.Mockito.verifyNoMoreInteractions;
 import static org.mockito.Mockito.when;
 
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.testing.NullPointerTester;
 import java.io.ByteArrayInputStream;
 import java.util.Arrays;
@@ -33,6 +34,7 @@
  * @author Qian Huang
  */
 @NullUnmarked
+@J2ktIncompatible
 public class HashingInputStreamTest extends TestCase {
   private Hasher hasher;
   private HashFunction hashFunction;

android/guava-tests/test/com/google/common/hash/HashingOutputStreamTest.java

@@ -20,6 +20,7 @@
 import static org.mockito.Mockito.verifyNoMoreInteractions;
 import static org.mockito.Mockito.when;
 
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.testing.NullPointerTester;
 import java.io.ByteArrayOutputStream;
 import junit.framework.TestCase;
@@ -31,6 +32,7 @@
  * @author Zoe Piepmeier
  */
 @NullUnmarked
+@J2ktIncompatible
 public class HashingOutputStreamTest extends TestCase {
   private Hasher hasher;
   private HashFunction hashFunction;