Improve obscure invalid identifier error message

Author: FlorentinD

graph-projection-api/src/main/java/org/neo4j/gds/ElementIdentifier.java

@@ -30,11 +30,11 @@ public abstract class ElementIdentifier {
 
     public final @NotNull String name;
 
-    ElementIdentifier(@NotNull String name) {
+    ElementIdentifier(@NotNull String name, String type) {
         if (name.equals(ElementProjection.PROJECT_ALL)) {
-            throw new IllegalArgumentException("name cannot be `*`");
+            throw new IllegalArgumentException(type + " cannot be `*`");
         } else if (StringFormatting.isEmpty(name)) {
-            throw new IllegalArgumentException("name cannot be empty");
+            throw new IllegalArgumentException(type + " cannot be empty");
         }
         this.name = name;
     }

graph-projection-api/src/main/java/org/neo4j/gds/NodeLabel.java

@@ -30,7 +30,7 @@ public class NodeLabel extends ElementIdentifier {
     public static final NodeLabel ALL_NODES = NodeLabel.of("__ALL__");
 
     public NodeLabel(String name) {
-        super(name);
+        super(name, "Node label");
     }
 
     @Override

graph-projection-api/src/main/java/org/neo4j/gds/RelationshipType.java

@@ -30,7 +30,7 @@ public class RelationshipType extends ElementIdentifier {
     public static final RelationshipType ALL_RELATIONSHIPS = RelationshipType.of("__ALL__");
 
     public RelationshipType(String name) {
-        super(name);
+        super(name, "Relationship type");
     }
 
     @Override

graph-projection-api/src/test/java/org/neo4j/gds/NodeLabelTest.java

@@ -0,0 +1,34 @@
+/*
+ * 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;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class NodeLabelTest {
+
+    @Test
+    void failOnInvalidName() {
+        assertThatThrownBy(() -> new NodeLabel("")).isInstanceOf(IllegalArgumentException.class)
+            .hasMessageMatching("Node label cannot be empty");
+    }
+
+}

graph-projection-api/src/test/java/org/neo4j/gds/RelationshipTypeTest.java

@@ -0,0 +1,34 @@
+/*
+ * 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;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class RelationshipTypeTest {
+
+    @Test
+    void failOnInvalidName() {
+        assertThatThrownBy(() -> new RelationshipType("")).isInstanceOf(IllegalArgumentException.class)
+            .hasMessageMatching("Relationship type cannot be empty");
+    }
+
+}