Add basic test for NodesFilter

Author: vnickolov

subgraph-filtering/src/test/java/org/neo4j/gds/beta/filter/NodesFilterTest.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.neo4j.gds.beta.filter;
+
+import org.junit.jupiter.api.Test;
+import org.neo4j.gds.NodeLabel;
+import org.neo4j.gds.api.GraphStore;
+import org.neo4j.gds.beta.filter.expression.ExpressionParser;
+import org.neo4j.gds.core.concurrency.Pools;
+import org.neo4j.gds.core.utils.progress.tasks.ProgressTracker;
+import org.neo4j.gds.extension.GdlExtension;
+import org.neo4j.gds.extension.GdlGraph;
+import org.neo4j.gds.extension.IdFunction;
+import org.neo4j.gds.extension.Inject;
+import org.opencypher.v9_0.parser.javacc.ParseException;
+
+import java.util.ArrayList;
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@GdlExtension
+class NodesFilterTest {
+
+    @GdlGraph(idOffset = 17)
+    private static final String DB_CYPHER =
+        "CREATE" +
+        "  (a:A {p: 1L})" +
+        ", (b:A {p: 2L})" +
+        ", (c:A {p: 3L})" +
+        ", (d:B)";
+
+    @Inject
+    GraphStore graphStore;
+
+    @Inject
+    IdFunction idFunction;
+
+    @Test
+    void basicFiltering() throws ParseException {
+        var filteredNodes = NodesFilter.filterNodes(
+            graphStore,
+            ExpressionParser.parse("n:A AND n.p > 1.0", Map.of()),
+            1,
+            Map.of(),
+            Pools.DEFAULT_SINGLE_THREAD_POOL,
+            ProgressTracker.NULL_TRACKER
+        );
+
+        var idMap = filteredNodes.idMap();
+        var filteredNodeIds = new ArrayList<Long>();
+
+        assertThat(idMap.availableNodeLabels())
+            .containsExactly(NodeLabel.of("A"));
+
+        idMap.forEachNode(n -> {
+            filteredNodeIds.add(idMap.toOriginalNodeId(n));
+            return true;
+        });
+
+        assertThat(filteredNodeIds)
+            .containsExactlyInAnyOrder(
+                idFunction.of("b"),
+                idFunction.of("c")
+            );
+    }
+}