dcapwell commented on code in PR #50: URL: https://github.com/apache/cassandra-accord/pull/50#discussion_r1261739482
########## accord-core/src/test/java/accord/utils/SimpleBitSetTest.java: ########## @@ -0,0 +1,203 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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 accord.utils; + +import java.util.ArrayList; +import java.util.BitSet; +import java.util.List; +import java.util.Random; +import java.util.function.BiConsumer; +import java.util.function.IntConsumer; + +import com.google.common.collect.Lists; +import org.junit.jupiter.api.Test; + +import static org.junit.jupiter.api.Assertions.assertEquals; + +public class SimpleBitSetTest +{ + private static final int NOT_FOUND = Integer.MAX_VALUE; + + private static class Check + { + final SimpleBitSet test; + final BitSet canon; + final int size; + + private Check(SimpleBitSet test, BitSet canon, int size) + { + this.test = test; + this.canon = canon; + this.size = size; + } + + void check(Random random) + { + assertEquals(canon.cardinality(), test.setBitCount()); + assertEquals(canon.nextSetBit(0), test.firstSetBit()); + assertEquals(normaliseNotFound(canon.nextSetBit(0)), test.firstSetBit(NOT_FOUND)); + assertEquals(canon.previousSetBit(size), test.lastSetBit()); + assertEquals(normaliseNotFound(canon.previousSetBit(size)), test.lastSetBit(NOT_FOUND)); + + forIndices(random, i -> assertEquals(canon.nextSetBit(i), test.nextSetBit(i))); + forIndices(random, i -> assertEquals(normaliseBefore(canon.nextSetBit(0), i), test.firstSetBitBefore(i))); + forIndices(random, i -> assertEquals(normaliseNotFoundBefore(canon.nextSetBit(0), i), test.firstSetBitBefore(i, NOT_FOUND))); + forRanges(random, (i, j) -> assertEquals(normaliseBefore(canon.nextSetBit(i), j), test.nextSetBitBefore(i, j))); + forRanges(random, (i, j) -> assertEquals(normaliseNotFoundBefore(canon.nextSetBit(i), j), test.nextSetBitBefore(i, j, NOT_FOUND))); + + forIndices(random, i -> assertEquals(i == 0 ? -1 : canon.previousSetBit(i - 1), test.prevSetBit(i))); + forIndices(random, i -> assertEquals(normaliseNotBefore(size == 0 ? -1 : canon.previousSetBit(size - 1), i), test.lastSetBitNotBefore(i))); + forIndices(random, i -> assertEquals(normaliseNotFoundNotBefore(size == 0 ? -1 : canon.previousSetBit(size - 1), i), test.lastSetBitNotBefore(i, NOT_FOUND))); + forRanges(random, (i, j) -> assertEquals(normaliseNotBefore(j == 0 ? -1 : canon.previousSetBit(j - 1), i), test.prevSetBitNotBefore(j, i))); + forRanges(random, (i, j) -> assertEquals(normaliseNotFoundNotBefore(j == 0 ? -1 : canon.previousSetBit(j - 1), i), test.prevSetBitNotBefore(j, i, NOT_FOUND))); + + List<Integer> canonCollect = new ArrayList<>(), testCollect = new ArrayList<>(); + canon.stream().forEachOrdered(canonCollect::add); + test.forEach(testCollect, List::add); + assertEquals(canonCollect, testCollect); + + canonCollect = Lists.reverse(canonCollect); + testCollect.clear(); + test.reverseForEach(testCollect, List::add); + assertEquals(canonCollect, testCollect); + } + + void forIndices(Random random, IntConsumer consumer) + { + for (int c = 0 ; c < 100 ; ++c) + { + int i = random.nextInt(size + 1); + consumer.accept(i); + } + } + + void forRanges(Random random, BiConsumer<Integer, Integer> consumer) + { + for (int c = 0 ; c < 100 ; ++c) + { + int i = random.nextInt(size + 1); + int j = random.nextInt(size + 1); + if (i > j) { int t = i; i = j; j = t; } + consumer.accept(i, j); + } + } + + static Check generate(Random random, int maxSize, int modCount, int runLength, float runChance, float clearChance) + { + int size = random.nextInt(maxSize); + runLength = Math.min(size, runLength); + BitSet canon = new BitSet(size); + SimpleBitSet test = new SimpleBitSet(size); + if (size > 0) + { + while (modCount-- > 0) + { + boolean set = random.nextFloat() >= clearChance; + boolean run = runLength > 1 && random.nextFloat() < runChance; + if (run) + { + int i = random.nextInt(size); + int j = random.nextInt(size); + if (j < i) { int t = i; i = j; j = t; } + j = Math.min(i + 1 + random.nextInt(runLength - 1), j); + + if (set) + { + canon.set(i, j); + test.setRange(i, j); + } + else + { + canon.clear(i, j); + while (i < j) + test.unset(i++); + } + } + else + { + int i = random.nextInt(size); + if (set) + { + assertEquals(!canon.get(i), test.set(i)); + canon.set(i); + } + else + { + assertEquals(canon.get(i), test.unset(i)); + canon.clear(i); + } + } + assertEquals(canon.cardinality(), test.setBitCount()); + } + } + return new Check(test, canon, size); + } + } + + @Test + public void testRandomBitSets() + { + Random random = new Random(); + long seed = random.nextLong(); + System.err.println("Seed: " + seed); + random.setSeed(seed); + testRandomBitSets(random, 100000); Review Comment: `qt` is our own function / logic. The reason I recommend this type of stuff rather than rolling our own random logic is that when failures are found most hand rolled solutions don't offer ways to repeat or even to know the seed when run in CI... by using `qt` you only have to think about your core logic and not how this runs in CI. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
