Custom functions cypherProperties and cypherSize fallback (#160)

translation/src/main/scala/org/opencypher/gremlin/translation/ir/rewrite/CustomFunctionFallback.scala

@@ -15,12 +15,12 @@
  */
 package org.opencypher.gremlin.translation.ir.rewrite
 
-import org.apache.tinkerpop.gremlin.structure.Column.values
+import org.apache.tinkerpop.gremlin.process.traversal.Scope.local
 import org.opencypher.gremlin.translation.Tokens.NULL
 import org.opencypher.gremlin.translation.exception.CypherExceptions
 import org.opencypher.gremlin.translation.ir.TraversalHelper._
 import org.opencypher.gremlin.translation.ir.model._
-import org.opencypher.gremlin.traversal.CustomFunction.{cypherException, cypherPlus}
+import org.opencypher.gremlin.traversal.CustomFunction.{cypherException, cypherPlus, cypherProperties, cypherSize}
 
 /**
   * Replaces Custom Functions with "The Best We Could Do" Gremlin native alternatives
@@ -37,6 +37,12 @@ object CustomFunctionFallback extends GremlinRewriter {
 
       case SelectC(values) :: MapF(function) :: rest if function.getName == cypherPlus().getName =>
         SelectC(values) :: Local(Unfold :: ChooseP(Neq(NULL), Sum :: Nil, Constant(NULL) :: Nil) :: Nil) :: rest
+
+      case MapF(function) :: rest if function.getName == cypherSize().getName =>
+        CountS(local) :: rest
+
+      case MapF(function) :: rest if function.getName == cypherProperties().getName =>
+        Local(Properties() :: Group :: By(Key :: Nil, None) :: By(MapT(Value :: Nil) :: Nil, None) :: Nil) :: rest
     }))(steps)
   }
 }

translation/src/test/java/org/opencypher/gremlin/translation/CypherAstTest.java

@@ -196,11 +196,11 @@ public void noCypherExtensions() {
             "MATCH (n:N) " +
                 "WITH n.p AS s " +
                 "WHERE s STARTS WITH 'x' AND s ENDS WITH 'x' AND s CONTAINS 'x' " +
-                "RETURN size(s), toString(s)"
+                "RETURN toString(s)"
         );
         Translator<String, GroovyPredicate> translator = Translator.builder().gremlinGroovy().build();
 
         assertThatThrownBy(() -> ast.buildTranslation(translator))
-            .hasMessageContaining("cypherContains, cypherEndsWith, cypherSize, cypherStarsWith, cypherToString");
+            .hasMessageContaining("cypherContains, cypherEndsWith, cypherStarsWith, cypherToString");
     }
 }

translation/src/test/scala/org/opencypher/gremlin/translation/ir/rewrite/CustomFunctionsFallbackTest.scala

@@ -15,6 +15,7 @@
  */
 package org.opencypher.gremlin.translation.ir.rewrite
 
+import org.apache.tinkerpop.gremlin.process.traversal.Scope
 import org.apache.tinkerpop.gremlin.structure.Column
 import org.junit.Test
 import org.opencypher.gremlin.translation.CypherAst.parse
@@ -61,4 +62,28 @@ class CustomFunctionsFallbackTest {
           .local(__.unfold().choose(P.neq(Tokens.NULL), __.sum(), __.start().constant(Tokens.NULL))))
   }
 
+  @Test
+  def cypherSizeFallback(): Unit = {
+    assertThat(parse("RETURN size($noType) AS a"))
+      .withFlavor(flavor)
+      .rewritingWith(CustomFunctionFallback)
+      .removes(__.map(CustomFunction.cypherSize()))
+      .adds(__.count(Scope.local))
+  }
+
+  @Test
+  def cypherPropertiesFallback(): Unit = {
+    assertThat(parse("RETURN properties($noType) AS a"))
+      .withFlavor(flavor)
+      .rewritingWith(CustomFunctionFallback)
+      .removes(__.map(CustomFunction.cypherProperties()))
+      .adds(
+        __.local(
+          __.properties()
+            .group()
+            .by(__.key())
+            .by(__.map(__.value()))
+        ))
+  }
+
 }

translation/src/test/scala/org/opencypher/gremlin/translation/ir/verify/NoCustomFunctionsTest.scala

@@ -35,11 +35,11 @@ class NoCustomFunctionsTest {
         |MATCH (n:N)
         |WITH n.p AS s
         |WHERE s STARTS WITH 'x' AND s ENDS WITH 'x' AND s CONTAINS 'x'
-        |RETURN size(s), toString(s)
+        |RETURN toString(s)
     """.stripMargin)
     val translator = Translator.builder.gremlinGroovy.build(flavor)
 
     assertThatThrownBy(() => ast.buildTranslation(translator))
-      .hasMessageContaining("cypherContains, cypherEndsWith, cypherSize, cypherStarsWith, cypherToString")
+      .hasMessageContaining("cypherContains, cypherEndsWith, cypherStarsWith, cypherToString")
   }
 }