Fix incorrect handling of !ignore custom tag in YAML (#3725)

This restores the proper comparison against `!ignore` tags in YAML.

This fixes #3727.

---------

Co-authored-by: Arnaud Lacurie <a_lacurie@apple.com>

Author: hatyo

yaml-tests/src/main/java/com/apple/foundationdb/relational/yamltests/Matchers.java

@@ -561,6 +561,10 @@ private static ResultSetMatchResult matchField(@Nullable final Object expected,
                                                    @Nullable final Object actual,
                                                    int rowNumber,
                                                    @Nonnull String cellRef) throws SQLException {
+        if (expected instanceof IgnoreTag.IgnoreMatcher) {
+            return ResultSetMatchResult.success();
+        }
+
         if (expected == null && actual == null) {
             return ResultSetMatchResult.success();
         }

yaml-tests/src/main/java/com/apple/foundationdb/relational/yamltests/tags/IgnoreTag.java

@@ -28,6 +28,7 @@
 import org.yaml.snakeyaml.nodes.Tag;
 
 import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 
 @AutoService(CustomTag.class)
 public final class IgnoreTag implements CustomTag {
@@ -36,7 +37,7 @@ public final class IgnoreTag implements CustomTag {
     private static final Tag tag = new Tag("!ignore");
 
     @Nonnull
-    private static final Matchable INSTANCE = (other, rowNumber, cellRef) -> Matchers.ResultSetMatchResult.success();
+    private static final Matchable INSTANCE = new IgnoreMatcher();
 
     @Nonnull
     private static final Construct CONSTRUCT_INSTANCE = new AbstractConstruct() {
@@ -60,4 +61,17 @@ public Tag getTag() {
     public Construct getConstruct() {
         return CONSTRUCT_INSTANCE;
     }
+
+    public static final class IgnoreMatcher implements Matchable {
+        @Nonnull
+        @Override
+        public Matchers.ResultSetMatchResult matches(@Nullable final Object other, final int rowNumber, @Nonnull final String cellRef) {
+            return Matchers.ResultSetMatchResult.success();
+        }
+
+        @Override
+        public String toString() {
+            return tag.getValue();
+        }
+    }
 }

yaml-tests/src/test/java/CustomTagTest.java

@@ -0,0 +1,67 @@
+/*
+ * CustomTagTest
+ *
+ * This source file is part of the FoundationDB open source project
+ *
+ * Copyright 2015-2025 Apple Inc. and the FoundationDB 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.
+ */
+
+import com.apple.foundationdb.relational.yamltests.YamlConnectionFactory;
+import com.apple.foundationdb.relational.yamltests.YamlExecutionContext;
+import com.apple.foundationdb.relational.yamltests.YamlRunner;
+import com.apple.foundationdb.relational.yamltests.configs.EmbeddedConfig;
+import com.apple.foundationdb.test.FDBTestEnvironment;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import javax.annotation.Nonnull;
+import java.util.stream.Stream;
+
+/**
+ * Tests for custom YAML tags such as {@link com.apple.foundationdb.relational.yamltests.tags.IgnoreTag}.
+ */
+class CustomTagTest {
+    private static final String CLUSTER_FILE = FDBTestEnvironment.randomClusterFile();
+    private static final EmbeddedConfig config = new EmbeddedConfig(CLUSTER_FILE);
+
+    @BeforeAll
+    static void beforeAll() throws Exception {
+        config.beforeAll();
+    }
+
+    @AfterAll
+    static void afterAll() throws Exception {
+        config.afterAll();
+    }
+
+    private void doRun(String testName, YamlConnectionFactory connectionFactory) throws Exception {
+        new YamlRunner(testName, connectionFactory, YamlExecutionContext.ContextOptions.EMPTY_OPTIONS).run();
+    }
+
+    @Nonnull
+    static Stream<String> shouldPass() {
+        return Stream.of(
+                "ignore-tag"
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource("shouldPass")
+    void shouldPass(String filename) throws Exception {
+        doRun("custom-tags/shouldPass/" + filename + ".yamsql", config.createConnectionFactory());
+    }
+}

yaml-tests/src/test/resources/custom-tags/shouldPass/ignore-tag.yamsql

@@ -0,0 +1,34 @@
+#
+# ignore-tag.yamsql
+#
+# This source file is part of the FoundationDB open source project
+#
+# Copyright 2021-2025 Apple Inc. and the FoundationDB 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.
+---
+schema_template:
+    create table t1(id bigint, col1 bigint, primary key(id))
+---
+test_block:
+  preset: single_repetition_ordered
+  tests:
+    -
+      - query: insert into t1 values (null, 200)
+      - count: 1
+    -
+      - query: select * from t1
+      - result: [{!ignore _, 200}]
+    -
+      - query: select col1 from t1
+      - result: [{!ignore _}]