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Posted to commits@tinkerpop.apache.org by sp...@apache.org on 2019/12/03 17:58:53 UTC

[tinkerpop] 01/23: TINKERPOP-2235 Allow null to work within Gremlin

This is an automated email from the ASF dual-hosted git repository.

spmallette pushed a commit to branch TINKERPOP-2235
in repository https://gitbox.apache.org/repos/asf/tinkerpop.git

commit 0ab7a52ddaecb5046b4f63b680d0071e90c95919
Author: stephen <sp...@gmail.com>
AuthorDate: Mon Nov 4 15:56:11 2019 -0500

    TINKERPOP-2235 Allow null to work within Gremlin
    
    In previous versions null as a value was not allowed as a Traverser in a Traversal. It was part of a filter in DefaultTraversal that would automatically remove it from the stream. While this was a design choice for Gremlin to use null that way, it removed a bit of functionality from Gremlin that could have use at times. As it so happened, the use of null as a filter really didn't need to work that way as we already had a secondary filter which was even better for representing an Empty [...]
---
 .../tinkerpop/gremlin/jsr223/JavaTranslator.java   |  2 +-
 .../tinkerpop/gremlin/process/traversal/Order.java |  8 ++++--
 .../gremlin/process/traversal/Traverser.java       |  9 ++++++-
 .../process/traversal/step/map/MapStep.java        | 16 +++++++++++-
 .../process/traversal/step/map/SelectOneStep.java  |  7 ++++-
 .../process/traversal/step/map/SelectStep.java     |  6 +++++
 .../traversal/step/map/TraversalMapStep.java       |  6 +++++
 .../process/traversal/step/util/AbstractStep.java  |  5 ++--
 .../traversal/traverser/B_O_S_SE_SL_Traverser.java |  2 +-
 .../traverser/util/AbstractTraverser.java          |  7 ++---
 .../traversal/traverser/util/EmptyTraverser.java   |  9 ++++++-
 .../gremlin/process/traversal/OrderTest.java       |  4 +++
 .../traverser/util/EmptyTraverserTest.java}        | 30 +++++++++-------------
 .../gremlin/util/iterator/ArrayIteratorTest.java   | 18 +++++++++++--
 .../groovy/jsr223/GroovyTranslatorProvider.java    |  4 ---
 .../ParameterizedGroovyTranslatorProvider.java     |  4 ---
 .../test/cucumber/feature-steps.js                 |  7 ++++-
 .../gremlin-javascript/test/unit/graphson-test.js  |  5 ++++
 .../gremlin_python/structure/io/graphbinaryV1.py   |  4 +++
 .../src/main/jython/radish/feature_steps.py        |  6 ++++-
 .../tests/structure/io/test_graphbinaryV1.py       |  9 +++++++
 .../jython/tests/structure/io/test_graphsonV2d0.py |  4 +++
 .../jython/tests/structure/io/test_graphsonV3d0.py |  4 +++
 .../GraphBinaryRemoteGraphComputerProvider.java    |  6 +----
 .../GraphSONRemoteGraphComputerProvider.java       |  6 +----
 .../remote/GryoRemoteGraphComputerProvider.java    |  6 +----
 ...emoteGraphGroovyTranslatorComputerProvider.java |  6 +----
 gremlin-test/features/sideEffect/Inject.feature    | 14 ++++++++++
 .../process/traversal/CoreTraversalTest.java       | 12 ---------
 .../traversal/step/sideEffect/InjectTest.java      | 14 ++++++++++
 .../strategy/decoration/TranslationStrategy.java   |  4 ++-
 ...tractTinkerGraphGraphSONTranslatorProvider.java |  4 ---
 .../io/gryo/TinkerGraphGryoTranslatorProvider.java |  4 ---
 33 files changed, 168 insertions(+), 84 deletions(-)

diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/jsr223/JavaTranslator.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/jsr223/JavaTranslator.java
index e71f112..515bc93 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/jsr223/JavaTranslator.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/jsr223/JavaTranslator.java
@@ -214,7 +214,7 @@ public final class JavaTranslator<S extends TraversalSource, T extends Traversal
                         for (int i = 0; i < parameters.length; i++) {
                             if (parameters[i].isVarArgs()) {
                                 final Class<?> parameterClass = parameters[i].getType().getComponentType();
-                                if (argumentsCopy.length > i && !parameterClass.isAssignableFrom(argumentsCopy[i].getClass())) {
+                                if (argumentsCopy.length > i && argumentsCopy[i] != null && !parameterClass.isAssignableFrom(argumentsCopy[i].getClass())) {
                                     found = false;
                                     break;
                                 }
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/Order.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/Order.java
index 34a61a7..1176f54 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/Order.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/Order.java
@@ -54,11 +54,13 @@ public enum Order implements Comparator<Object> {
      * @since 3.3.4
      */
     asc {
+        private final Comparator<Comparable> ascendingComparator = Comparator.nullsFirst(Comparator.<Comparable>naturalOrder());
+
         @Override
         public int compare(final Object first, final Object second) {
             return first instanceof Number && second instanceof Number
                     ? NumberHelper.compare((Number) first, (Number) second)
-                    : Comparator.<Comparable>naturalOrder().compare((Comparable) first, (Comparable) second);
+                    : ascendingComparator.compare((Comparable) first, (Comparable) second);
         }
 
         @Override
@@ -73,11 +75,13 @@ public enum Order implements Comparator<Object> {
      * @since 3.3.4
      */
     desc {
+        private final Comparator<Comparable> descendingComparator = Comparator.nullsLast(Comparator.<Comparable>reverseOrder());
+
         @Override
         public int compare(final Object first, final Object second) {
             return first instanceof Number && second instanceof Number
                     ? NumberHelper.compare((Number) second, (Number) first)
-                    : Comparator.<Comparable>reverseOrder().compare((Comparable) first, (Comparable) second);
+                    : descendingComparator.compare((Comparable) first, (Comparable) second);
         }
 
         @Override
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/Traverser.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/Traverser.java
index e07bec1..fc58c62 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/Traverser.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/Traverser.java
@@ -18,9 +18,11 @@
  */
 package org.apache.tinkerpop.gremlin.process.traversal;
 
+import org.apache.tinkerpop.gremlin.process.traversal.step.map.LoopsStep;
 import org.apache.tinkerpop.gremlin.structure.util.Attachable;
 
 import java.io.Serializable;
+import java.util.Comparator;
 import java.util.Set;
 import java.util.function.Function;
 
@@ -134,7 +136,12 @@ public interface Traverser<T> extends Serializable, Comparable<Traverser<T>>, Cl
      */
     @Override
     public default int compareTo(final Traverser<T> other) throws ClassCastException {
-        return ((Comparable) this.get()).compareTo(other.get());
+        final Object thisObj = this.get();
+        final Object otherObj = other.get();
+        if (thisObj == otherObj) return 0;
+        if (null == thisObj) return -1;
+        if (null == otherObj) return 1;
+        return ((Comparable) thisObj).compareTo(otherObj);
     }
 
     /**
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/MapStep.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/MapStep.java
index 03e544e..2747b9c 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/MapStep.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/MapStep.java
@@ -21,6 +21,7 @@ package org.apache.tinkerpop.gremlin.process.traversal.step.map;
 import org.apache.tinkerpop.gremlin.process.traversal.Traversal;
 import org.apache.tinkerpop.gremlin.process.traversal.Traverser;
 import org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep;
+import org.apache.tinkerpop.gremlin.process.traversal.traverser.util.EmptyTraverser;
 
 /**
  * @author Marko A. Rodriguez (http://markorodriguez.com)
@@ -34,10 +35,23 @@ public abstract class MapStep<S, E> extends AbstractStep<S, E> {
     @Override
     protected Traverser.Admin<E> processNextStart() {
         final Traverser.Admin<S> traverser = this.starts.next();
-        return traverser.split(this.map(traverser), this);
+        final E obj = this.map(traverser);
+
+        // maybe looks tricky, but it's just a play on Java generics without having to tear apart every MapStep
+        // instance. basically just want to respect the fact that a subclass can return an EmptyTraverser from
+        // map() and if so, just return that empty.
+        return isEmptyTraverser(obj) ? EmptyTraverser.instance() : traverser.split(obj, this);
     }
 
     protected abstract E map(final Traverser.Admin<S> traverser);
 
+    /**
+     * Determines if the value returned from {@link #map(Traverser.Admin)} should be representative of an
+     * {@link EmptyTraverser}. Such traversers will effectively be filtered out by the traversal.
+     */
+    protected boolean isEmptyTraverser(E obj) {
+        return false;
+    }
+
 }
 
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/SelectOneStep.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/SelectOneStep.java
index 2c7aa82..98ee83f 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/SelectOneStep.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/SelectOneStep.java
@@ -26,7 +26,7 @@ import org.apache.tinkerpop.gremlin.process.traversal.step.PathProcessor;
 import org.apache.tinkerpop.gremlin.process.traversal.step.Scoping;
 import org.apache.tinkerpop.gremlin.process.traversal.step.TraversalParent;
 import org.apache.tinkerpop.gremlin.process.traversal.traverser.TraverserRequirement;
-import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalHelper;
+import org.apache.tinkerpop.gremlin.process.traversal.traverser.util.EmptyTraverser;
 import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalUtil;
 import org.apache.tinkerpop.gremlin.structure.util.StringFactory;
 
@@ -58,6 +58,11 @@ public final class SelectOneStep<S, E> extends MapStep<S, E> implements Traversa
     }
 
     @Override
+    protected boolean isEmptyTraverser(final E obj) {
+        return null == obj;
+    }
+
+    @Override
     public String toString() {
         return StringFactory.stepString(this, this.pop, this.selectKey, this.selectTraversal);
     }
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/SelectStep.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/SelectStep.java
index 875cf93..db15a28 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/SelectStep.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/SelectStep.java
@@ -26,6 +26,7 @@ import org.apache.tinkerpop.gremlin.process.traversal.step.PathProcessor;
 import org.apache.tinkerpop.gremlin.process.traversal.step.Scoping;
 import org.apache.tinkerpop.gremlin.process.traversal.step.TraversalParent;
 import org.apache.tinkerpop.gremlin.process.traversal.traverser.TraverserRequirement;
+import org.apache.tinkerpop.gremlin.process.traversal.traverser.util.EmptyTraverser;
 import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalHelper;
 import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalRing;
 import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalUtil;
@@ -77,6 +78,11 @@ public final class SelectStep<S, E> extends MapStep<S, Map<String, E>> implement
     }
 
     @Override
+    protected boolean isEmptyTraverser(final Map<String, E> obj) {
+        return null == obj;
+    }
+
+    @Override
     public void reset() {
         super.reset();
         this.traversalRing.reset();
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/TraversalMapStep.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/TraversalMapStep.java
index 896b833..32c2e3c 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/TraversalMapStep.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/TraversalMapStep.java
@@ -22,6 +22,7 @@ import org.apache.tinkerpop.gremlin.process.traversal.Traversal;
 import org.apache.tinkerpop.gremlin.process.traversal.Traverser;
 import org.apache.tinkerpop.gremlin.process.traversal.step.TraversalParent;
 import org.apache.tinkerpop.gremlin.process.traversal.traverser.TraverserRequirement;
+import org.apache.tinkerpop.gremlin.process.traversal.traverser.util.EmptyTraverser;
 import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalUtil;
 import org.apache.tinkerpop.gremlin.structure.util.StringFactory;
 
@@ -49,6 +50,11 @@ public final class TraversalMapStep<S, E> extends MapStep<S, E> implements Trave
     }
 
     @Override
+    protected boolean isEmptyTraverser(final E obj) {
+        return null == obj;
+    }
+
+    @Override
     public List<Traversal.Admin<S, E>> getLocalChildren() {
         return Collections.singletonList(this.mapTraversal);
     }
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/util/AbstractStep.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/util/AbstractStep.java
index e2757e2..fe49e56 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/util/AbstractStep.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/util/AbstractStep.java
@@ -21,6 +21,7 @@ package org.apache.tinkerpop.gremlin.process.traversal.step.util;
 import org.apache.tinkerpop.gremlin.process.traversal.Step;
 import org.apache.tinkerpop.gremlin.process.traversal.Traversal;
 import org.apache.tinkerpop.gremlin.process.traversal.Traverser;
+import org.apache.tinkerpop.gremlin.process.traversal.traverser.util.EmptyTraverser;
 import org.apache.tinkerpop.gremlin.process.traversal.util.EmptyTraversal;
 import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalInterruptedException;
 import org.apache.tinkerpop.gremlin.structure.util.StringFactory;
@@ -126,7 +127,7 @@ public abstract class AbstractStep<S, E> implements Step<S, E> {
             while (true) {
                 if (Thread.interrupted()) throw new TraversalInterruptedException();
                 final Traverser.Admin<E> traverser = this.processNextStart();
-                if (null != traverser.get() && 0 != traverser.bulk())
+                if (traverser.bulk() > 0)
                     return this.prepareTraversalForNextStep(traverser);
             }
         }
@@ -141,7 +142,7 @@ public abstract class AbstractStep<S, E> implements Step<S, E> {
                 while (true) {
                     if (Thread.interrupted()) throw new TraversalInterruptedException();
                     this.nextEnd = this.processNextStart();
-                    if (null != this.nextEnd.get() && 0 != this.nextEnd.bulk())
+                    if (this.nextEnd.bulk() > 0)
                         return true;
                     else
                         this.nextEnd = null;
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/B_O_S_SE_SL_Traverser.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/B_O_S_SE_SL_Traverser.java
index 33c5520..57fa47a 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/B_O_S_SE_SL_Traverser.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/B_O_S_SE_SL_Traverser.java
@@ -136,7 +136,7 @@ public class B_O_S_SE_SL_Traverser<T> extends B_O_Traverser<T> {
 
     protected final boolean equals(final B_O_S_SE_SL_Traverser other) {
         return super.equals(other) && other.loops == this.loops
-                && (this.loopName != null ? this.loopName.equals(other.loopName) : other.loopName == null)
+                && Objects.equals(this.loopName, other.loopName)
                 && !carriesUnmergeableSack();
     }
 
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/AbstractTraverser.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/AbstractTraverser.java
index 658ba4b..e76016a 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/AbstractTraverser.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/AbstractTraverser.java
@@ -27,6 +27,7 @@ import org.apache.tinkerpop.gremlin.process.traversal.util.EmptyTraversalSideEff
 import org.apache.tinkerpop.gremlin.structure.util.Attachable;
 import org.apache.tinkerpop.gremlin.structure.util.reference.ReferenceFactory;
 
+import java.util.Objects;
 import java.util.Set;
 import java.util.function.Function;
 
@@ -203,16 +204,16 @@ public abstract class AbstractTraverser<T> implements Traverser<T>, Traverser.Ad
 
     @Override
     public int hashCode() {
-        return this.t.hashCode();
+        return Objects.hashCode(this.t);
     }
 
     @Override
     public boolean equals(final Object object) {
-        return object instanceof AbstractTraverser && ((AbstractTraverser) object).get().equals(this.t);
+        return object instanceof AbstractTraverser && Objects.equals(this.t, ((AbstractTraverser) object).t);
     }
 
     @Override
     public String toString() {
-        return this.t.toString();
+        return Objects.toString(this.t);
     }
 }
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/EmptyTraverser.java b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/EmptyTraverser.java
index 3aeafbd..c68fdc6 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/EmptyTraverser.java
+++ b/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/EmptyTraverser.java
@@ -20,6 +20,7 @@ package org.apache.tinkerpop.gremlin.process.traversal.traverser.util;
 
 import org.apache.tinkerpop.gremlin.process.traversal.Path;
 import org.apache.tinkerpop.gremlin.process.traversal.Step;
+import org.apache.tinkerpop.gremlin.process.traversal.Traversal;
 import org.apache.tinkerpop.gremlin.process.traversal.TraversalSideEffects;
 import org.apache.tinkerpop.gremlin.process.traversal.Traverser;
 import org.apache.tinkerpop.gremlin.process.traversal.step.util.EmptyPath;
@@ -30,12 +31,18 @@ import java.util.Set;
 import java.util.function.Function;
 
 /**
+ * A {@link Traverser} with no bulk which effectively means that it will no longer be propagated through a
+ * {@link Traversal}.
+ *
  * @author Marko A. Rodriguez (http://markorodriguez.com)
  */
 public final class EmptyTraverser<T> implements Traverser<T>, Traverser.Admin<T> {
 
     private static final EmptyTraverser INSTANCE = new EmptyTraverser();
 
+    /**
+     * The empty {@link Traverser} instance.
+     */
     public static <R> EmptyTraverser<R> instance() {
         return INSTANCE;
     }
@@ -95,7 +102,7 @@ public final class EmptyTraverser<T> implements Traverser<T>, Traverser.Admin<T>
     }
 
     @Override
-    public void setBulk(long count) {
+    public void setBulk(final long count) {
 
     }
 
diff --git a/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/OrderTest.java b/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/OrderTest.java
index a70cfc8..d094772 100644
--- a/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/OrderTest.java
+++ b/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/OrderTest.java
@@ -43,13 +43,17 @@ public class OrderTest {
     @Parameterized.Parameters(name = "{0}.test({1},{2})")
     public static Iterable<Object[]> data() throws ParseException {
         return new ArrayList<>(Arrays.asList(new Object[][]{
+                {Order.asc, Arrays.asList("a", "c", null, "d"), Arrays.asList(null, "a", "c", "d")},
                 {Order.asc, Arrays.asList("b", "a", "c", "d"), Arrays.asList("a", "b", "c", "d")},
                 {Order.desc, Arrays.asList("b", "a", "c", "d"), Arrays.asList("d", "c", "b", "a")},
+                {Order.desc, Arrays.asList("c", "a", null, "d"), Arrays.asList("d", "c", "a", null)},
                 {Order.asc, Arrays.asList(formatter.parse("1-Jan-2018"), formatter.parse("1-Jan-2020"), formatter.parse("1-Jan-2008")),
                             Arrays.asList(formatter.parse("1-Jan-2008"), formatter.parse("1-Jan-2018"), formatter.parse("1-Jan-2020"))},
                 {Order.desc, Arrays.asList(formatter.parse("1-Jan-2018"), formatter.parse("1-Jan-2020"), formatter.parse("1-Jan-2008")),
                              Arrays.asList(formatter.parse("1-Jan-2020"), formatter.parse("1-Jan-2018"), formatter.parse("1-Jan-2008"))},
+                {Order.desc, Arrays.asList(100L, 1L, null, -1L, 0L), Arrays.asList(100L, 1L, 0L, -1L, null)},
                 {Order.desc, Arrays.asList(100L, 1L, -1L, 0L), Arrays.asList(100L, 1L, 0L, -1L)},
+                {Order.asc, Arrays.asList(100L, 1L, null, -1L, 0L), Arrays.asList(null, -1L, 0L, 1L, 100L)},
                 {Order.asc, Arrays.asList(100.1f, 1.1f, -1.1f, 0.1f), Arrays.asList(-1.1f, 0.1f, 1.1f, 100.1f)},
                 {Order.desc, Arrays.asList(100.1f, 1.1f, -1.1f, 0.1f), Arrays.asList(100.1f, 1.1f, 0.1f, -1.1f)},
                 {Order.asc, Arrays.asList(100.1d, 1.1d, -1.1d, 0.1d), Arrays.asList(-1.1d, 0.1d, 1.1d, 100.1d)},
diff --git a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/MapStep.java b/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/EmptyTraverserTest.java
similarity index 52%
copy from gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/MapStep.java
copy to gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/EmptyTraverserTest.java
index 03e544e..da41900 100644
--- a/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/MapStep.java
+++ b/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/EmptyTraverserTest.java
@@ -16,28 +16,22 @@
  * specific language governing permissions and limitations
  * under the License.
  */
-package org.apache.tinkerpop.gremlin.process.traversal.step.map;
+package org.apache.tinkerpop.gremlin.process.traversal.traverser.util;
 
-import org.apache.tinkerpop.gremlin.process.traversal.Traversal;
-import org.apache.tinkerpop.gremlin.process.traversal.Traverser;
-import org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep;
+import org.junit.Test;
 
-/**
- * @author Marko A. Rodriguez (http://markorodriguez.com)
- */
-public abstract class MapStep<S, E> extends AbstractStep<S, E> {
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertSame;
 
-    public MapStep(final Traversal.Admin traversal) {
-        super(traversal);
-    }
+public class EmptyTraverserTest {
 
-    @Override
-    protected Traverser.Admin<E> processNextStart() {
-        final Traverser.Admin<S> traverser = this.starts.next();
-        return traverser.split(this.map(traverser), this);
+    @Test
+    public void shouldHaveSameInstance() {
+        assertSame(EmptyTraverser.instance(), EmptyTraverser.instance());
     }
 
-    protected abstract E map(final Traverser.Admin<S> traverser);
-
+    @Test
+    public void shouldHaveZeroBulk() {
+        assertEquals(0, EmptyTraverser.instance().bulk());
+    }
 }
-
diff --git a/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/util/iterator/ArrayIteratorTest.java b/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/util/iterator/ArrayIteratorTest.java
index 60ddd88..32f7401 100644
--- a/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/util/iterator/ArrayIteratorTest.java
+++ b/gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/util/iterator/ArrayIteratorTest.java
@@ -23,8 +23,7 @@ import org.junit.Test;
 
 import java.util.Iterator;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.*;
 
 /**
  * @author Stephen Mallette (http://stephen.genoprime.com)
@@ -45,6 +44,21 @@ public class ArrayIteratorTest {
         assertFalse(itty.hasNext());
     }
 
+    @Test
+    public void shouldIterateAnArrayWithNull() {
+        final String[] arr = new String[3];
+        arr[0] = "test1";
+        arr[1] = "test2";
+        arr[2] = null;
+
+        final Iterator<String> itty = new ArrayIterator<>(arr);
+        assertEquals("test1", itty.next());
+        assertEquals("test2", itty.next());
+        assertNull(itty.next());
+
+        assertFalse(itty.hasNext());
+    }
+
     @Test(expected = FastNoSuchElementException.class)
     public void shouldThrowFastNoSuchElementException() {
         final Iterator<String> itty = new ArrayIterator<>(new String[0]);
diff --git a/gremlin-groovy/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/GroovyTranslatorProvider.java b/gremlin-groovy/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/GroovyTranslatorProvider.java
index 5f556b8..b4d2452 100644
--- a/gremlin-groovy/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/GroovyTranslatorProvider.java
+++ b/gremlin-groovy/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/GroovyTranslatorProvider.java
@@ -207,10 +207,6 @@ import org.apache.tinkerpop.gremlin.util.TinkerGraphProvider;
         method = "shouldNeverPropagateANoBulkTraverser",
         reason = "Reason requires investigation")
 @Graph.OptOut(
-        test = "org.apache.tinkerpop.gremlin.process.traversal.CoreTraversalTest",
-        method = "shouldNeverPropagateANullValuedTraverser",
-        reason = "Reason requires investigation")
-@Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.ReadTest",
         method = "*",
         reason = "read and write tests don't translate locally well because of calling iterate() inside read()/write() add a none()")
diff --git a/gremlin-groovy/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/ParameterizedGroovyTranslatorProvider.java b/gremlin-groovy/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/ParameterizedGroovyTranslatorProvider.java
index 2e60cba..56466a5 100644
--- a/gremlin-groovy/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/ParameterizedGroovyTranslatorProvider.java
+++ b/gremlin-groovy/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/ParameterizedGroovyTranslatorProvider.java
@@ -207,10 +207,6 @@ import org.apache.tinkerpop.gremlin.util.TinkerGraphProvider;
         method = "shouldNeverPropagateANoBulkTraverser",
         reason = "Reason requires investigation")
 @Graph.OptOut(
-        test = "org.apache.tinkerpop.gremlin.process.traversal.CoreTraversalTest",
-        method = "shouldNeverPropagateANullValuedTraverser",
-        reason = "Reason requires investigation")
-@Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.ReadTest",
         method = "*",
         reason = "read and write tests don't translate locally well because of calling iterate() inside read()/write() add a none()")
diff --git a/gremlin-javascript/src/main/javascript/gremlin-javascript/test/cucumber/feature-steps.js b/gremlin-javascript/src/main/javascript/gremlin-javascript/test/cucumber/feature-steps.js
index fed551d..d85d678 100644
--- a/gremlin-javascript/src/main/javascript/gremlin-javascript/test/cucumber/feature-steps.js
+++ b/gremlin-javascript/src/main/javascript/gremlin-javascript/test/cucumber/feature-steps.js
@@ -223,6 +223,10 @@ function parseRow(row) {
 }
 
 function parseValue(stringValue) {
+
+  if(stringValue === "null")
+    return null;
+
   let extractedValue = null;
   let parser = null;
   for (let item of parsers) {
@@ -234,6 +238,7 @@ function parseValue(stringValue) {
       break;
     }
   }
+
   return parser !== null ? parser.call(this, extractedValue) : stringValue;
 }
 
@@ -279,7 +284,7 @@ function toT(value) {
 }
 
 function toDirection(value) {
-    return direction[value.toLowerCase()];
+  return direction[value.toLowerCase()];
 }
 
 function toArray(stringList) {
diff --git a/gremlin-javascript/src/main/javascript/gremlin-javascript/test/unit/graphson-test.js b/gremlin-javascript/src/main/javascript/gremlin-javascript/test/unit/graphson-test.js
index f355fb5..2942d01 100644
--- a/gremlin-javascript/src/main/javascript/gremlin-javascript/test/unit/graphson-test.js
+++ b/gremlin-javascript/src/main/javascript/gremlin-javascript/test/unit/graphson-test.js
@@ -32,6 +32,11 @@ const GraphSONWriter = gs.GraphSONWriter;
 const P = t.P;
 
 describe('GraphSONReader', function () {
+  it('should parse GraphSON null', function () {
+    const reader = new GraphSONReader();
+    const result = reader.read(null);
+    assert.equal(result, null);
+  });
   it('should parse GraphSON int32, float and double to Number from GraphSON', function () {
     const reader = new GraphSONReader();
     [
diff --git a/gremlin-python/src/main/jython/gremlin_python/structure/io/graphbinaryV1.py b/gremlin-python/src/main/jython/gremlin_python/structure/io/graphbinaryV1.py
index c06ee12..b5aca52 100644
--- a/gremlin-python/src/main/jython/gremlin_python/structure/io/graphbinaryV1.py
+++ b/gremlin-python/src/main/jython/gremlin_python/structure/io/graphbinaryV1.py
@@ -156,6 +156,10 @@ class GraphBinaryWriter(object):
         if to_extend is None:
             to_extend = bytearray()
 
+        if obj is None:
+            to_extend.extend(NULL_BYTES)
+            return
+
         try:
             t = type(obj)
             
diff --git a/gremlin-python/src/main/jython/radish/feature_steps.py b/gremlin-python/src/main/jython/radish/feature_steps.py
index 441a3fb..6514f3c 100644
--- a/gremlin-python/src/main/jython/radish/feature_steps.py
+++ b/gremlin-python/src/main/jython/radish/feature_steps.py
@@ -38,6 +38,7 @@ regex_or = re.compile(r"([(.,\s])or\(")
 regex_with = re.compile(r"([(.,\s])with\(")
 regex_true = re.compile(r"(true)")
 regex_false = re.compile(r"(false)")
+regex_null = re.compile(r"(null)")
 
 outV = __.outV
 label = __.label
@@ -182,6 +183,8 @@ def _convert(val, ctx):
         return T[val[2:-1]]
     elif isinstance(val, str) and re.match("^D\[.*\]$", val):           # parse instance of Direction enum
         return Direction[val[2:-1]]
+    elif isinstance(val, str) and re.match("^null$", val):              # parse null to None
+        return None
     else:
         return val
 
@@ -247,7 +250,8 @@ def _translate(traversal_):
     replaced = regex_in.sub(r"\1in_(", replaced)
     replaced = regex_with.sub(r"\1with_(", replaced)
     replaced = regex_true.sub(r"True", replaced)
-    return regex_false.sub(r"False", replaced)
+    replaced = regex_false.sub(r"False", replaced)
+    return regex_null.sub(r"None", replaced)
 
 
 def _make_traversal(g, traversal_string, params):
diff --git a/gremlin-python/src/main/jython/tests/structure/io/test_graphbinaryV1.py b/gremlin-python/src/main/jython/tests/structure/io/test_graphbinaryV1.py
index a2320bc..7416a94 100644
--- a/gremlin-python/src/main/jython/tests/structure/io/test_graphbinaryV1.py
+++ b/gremlin-python/src/main/jython/tests/structure/io/test_graphbinaryV1.py
@@ -44,6 +44,10 @@ class TestGraphSONWriter(object):
     graphbinary_writer = GraphBinaryWriter()
     graphbinary_reader = GraphBinaryReader()
 
+    def test_null(self):
+        c = self.graphbinary_reader.readObject(self.graphbinary_writer.writeObject(None))
+        assert c is None
+
     def test_int(self):
         x = 100
         output = self.graphbinary_reader.readObject(self.graphbinary_writer.writeObject(x))
@@ -101,6 +105,11 @@ class TestGraphSONWriter(object):
         output = self.graphbinary_reader.readObject(self.graphbinary_writer.writeObject(x))
         assert x == output
 
+    def test_heterogeneous_list_with_none(self):
+        x = ["serialize this!", 0, "serialize that!", "serialize that!", 1, "stop telling me what to serialize", 2, None]
+        output = self.graphbinary_reader.readObject(self.graphbinary_writer.writeObject(x))
+        assert x == output
+
     def test_homogeneous_set(self):
         x = {"serialize this!", "serialize that!", "stop telling me what to serialize"}
         output = self.graphbinary_reader.readObject(self.graphbinary_writer.writeObject(x))
diff --git a/gremlin-python/src/main/jython/tests/structure/io/test_graphsonV2d0.py b/gremlin-python/src/main/jython/tests/structure/io/test_graphsonV2d0.py
index 1f54736..cebe29c 100644
--- a/gremlin-python/src/main/jython/tests/structure/io/test_graphsonV2d0.py
+++ b/gremlin-python/src/main/jython/tests/structure/io/test_graphsonV2d0.py
@@ -289,6 +289,10 @@ class TestGraphSONReader(object):
         assert isinstance(c, SingleChar)
         assert chr(76) == c
 
+    def test_null(self):
+        c = self.graphson_reader.readObject(json.dumps(None))
+        assert c is None
+
 
 class TestGraphSONWriter(object):
     graphson_writer = GraphSONWriter()
diff --git a/gremlin-python/src/main/jython/tests/structure/io/test_graphsonV3d0.py b/gremlin-python/src/main/jython/tests/structure/io/test_graphsonV3d0.py
index d68e5be..9366937 100644
--- a/gremlin-python/src/main/jython/tests/structure/io/test_graphsonV3d0.py
+++ b/gremlin-python/src/main/jython/tests/structure/io/test_graphsonV3d0.py
@@ -336,6 +336,10 @@ class TestGraphSONReader(object):
         assert isinstance(c, SingleChar)
         assert chr(76) == c
 
+    def test_null(self):
+        c = self.graphson_reader.readObject(json.dumps(None))
+        assert c is None
+
 
 class TestGraphSONWriter(object):
     graphson_writer = GraphSONWriter()
diff --git a/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GraphBinaryRemoteGraphComputerProvider.java b/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GraphBinaryRemoteGraphComputerProvider.java
index 2133a0b..57d0a28 100644
--- a/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GraphBinaryRemoteGraphComputerProvider.java
+++ b/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GraphBinaryRemoteGraphComputerProvider.java
@@ -85,11 +85,7 @@ import org.apache.tinkerpop.gremlin.tinkergraph.process.computer.TinkerGraphComp
         reason = "Local traversals may not traverse past the local star-graph on GraphComputer")
 @Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.InjectTest",
-        method = "g_VX1X_injectXg_VX4XX_out_name",
-        reason = "The inject() step is not supported by GraphComputer")
-@Graph.OptOut(
-        test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.InjectTest",
-        method = "g_VX1X_out_injectXv2X_name",
+        method = "*",
         reason = "The inject() step is not supported by GraphComputer")
 @Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.branch.LocalTest",
diff --git a/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GraphSONRemoteGraphComputerProvider.java b/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GraphSONRemoteGraphComputerProvider.java
index 7b80c2c..100aef6 100644
--- a/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GraphSONRemoteGraphComputerProvider.java
+++ b/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GraphSONRemoteGraphComputerProvider.java
@@ -85,11 +85,7 @@ import org.apache.tinkerpop.gremlin.tinkergraph.process.computer.TinkerGraphComp
         reason = "Local traversals may not traverse past the local star-graph on GraphComputer")
 @Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.InjectTest",
-        method = "g_VX1X_injectXg_VX4XX_out_name",
-        reason = "The inject() step is not supported by GraphComputer")
-@Graph.OptOut(
-        test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.InjectTest",
-        method = "g_VX1X_out_injectXv2X_name",
+        method = "*",
         reason = "The inject() step is not supported by GraphComputer")
 @Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.branch.LocalTest",
diff --git a/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GryoRemoteGraphComputerProvider.java b/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GryoRemoteGraphComputerProvider.java
index 1269322..ba0ccda 100644
--- a/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GryoRemoteGraphComputerProvider.java
+++ b/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/driver/remote/GryoRemoteGraphComputerProvider.java
@@ -86,11 +86,7 @@ import org.apache.tinkerpop.gremlin.tinkergraph.process.computer.TinkerGraphComp
         reason = "Local traversals may not traverse past the local star-graph on GraphComputer")
 @Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.InjectTest",
-        method = "g_VX1X_injectXg_VX4XX_out_name",
-        reason = "The inject() step is not supported by GraphComputer")
-@Graph.OptOut(
-        test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.InjectTest",
-        method = "g_VX1X_out_injectXv2X_name",
+        method = "*",
         reason = "The inject() step is not supported by GraphComputer")
 @Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.branch.LocalTest",
diff --git a/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/GryoRemoteGraphGroovyTranslatorComputerProvider.java b/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/GryoRemoteGraphGroovyTranslatorComputerProvider.java
index 77fa5f6..5cfe2fe 100644
--- a/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/GryoRemoteGraphGroovyTranslatorComputerProvider.java
+++ b/gremlin-server/src/test/java/org/apache/tinkerpop/gremlin/groovy/jsr223/GryoRemoteGraphGroovyTranslatorComputerProvider.java
@@ -88,11 +88,7 @@ import org.apache.tinkerpop.gremlin.tinkergraph.process.computer.TinkerGraphComp
         reason = "Local traversals may not traverse past the local star-graph on GraphComputer")
 @Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.InjectTest",
-        method = "g_VX1X_injectXg_VX4XX_out_name",
-        reason = "The inject() step is not supported by GraphComputer")
-@Graph.OptOut(
-        test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.InjectTest",
-        method = "g_VX1X_out_injectXv2X_name",
+        method = "*",
         reason = "The inject() step is not supported by GraphComputer")
 @Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.branch.LocalTest",
diff --git a/gremlin-test/features/sideEffect/Inject.feature b/gremlin-test/features/sideEffect/Inject.feature
index 740928d..db5a26c 100644
--- a/gremlin-test/features/sideEffect/Inject.feature
+++ b/gremlin-test/features/sideEffect/Inject.feature
@@ -66,3 +66,17 @@ Feature: Step - inject()
       | lop   |
       | vadas |
       | josh  |
+
+  Scenario: g_injectXnull_1_3_nullX
+    Given the empty graph
+    And the traversal of
+      """
+      g.inject(null, 1, 3, null)
+      """
+    When iterated to list
+    Then the result should be unordered
+      | result |
+      | null |
+      | d[1].i |
+      | d[3].i |
+      | null |
\ No newline at end of file
diff --git a/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/CoreTraversalTest.java b/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/CoreTraversalTest.java
index 04417a0..92794c5 100644
--- a/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/CoreTraversalTest.java
+++ b/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/CoreTraversalTest.java
@@ -78,18 +78,6 @@ public class CoreTraversalTest extends AbstractGremlinProcessTest {
     }
 
     @Test
-    @LoadGraphWith
-    public void shouldNeverPropagateANullValuedTraverser() {
-        try {
-            assertFalse(g.V().map(t -> null).hasNext());
-            assertEquals(0, g.V().map(t -> null).toList().size());
-            g.V().map(t -> null).sideEffect(t -> fail("this should not have happened")).iterate();
-        } catch (VerificationException e) {
-            // its okay if lambdas can't be serialized by the test suite
-        }
-    }
-
-    @Test
     @LoadGraphWith(MODERN)
     public void shouldFilterOnIterate() {
         final Traversal<Vertex,String> traversal = g.V().out().out().<String>values("name").aggregate("x").iterate();
diff --git a/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/sideEffect/InjectTest.java b/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/sideEffect/InjectTest.java
index d3fc1ed..0b3b584 100644
--- a/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/sideEffect/InjectTest.java
+++ b/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/sideEffect/InjectTest.java
@@ -48,6 +48,8 @@ public abstract class InjectTest extends AbstractGremlinProcessTest {
 
     public abstract Traversal<Vertex, String> get_g_VX1X_injectXg_VX4XX_out_name(final Object v1Id, final Object v4Id);
 
+    public abstract Traversal<Integer, Integer> get_g_injectXnull_1_3_nullX();
+
     @Test
     @LoadGraphWith(MODERN)
     public void g_VX1X_out_injectXv2X_name() {
@@ -85,6 +87,13 @@ public abstract class InjectTest extends AbstractGremlinProcessTest {
     }
 
     @Test
+    public void g_injectXnull_1_3_nullX() {
+        final Traversal<Integer, Integer> traversal = get_g_injectXnull_1_3_nullX();
+        printTraversalForm(traversal);
+        checkResults(Arrays.asList(null, 1, 3, null), traversal);
+    }
+
+    @Test
     @LoadGraphWith(MODERN)
     public void g_VX1X_injectXg_VX4XX_out_name() {
         final Traversal<Vertex, String> traversal = get_g_VX1X_injectXg_VX4XX_out_name(convertToVertexId("marko"), convertToVertexId("josh"));
@@ -108,5 +117,10 @@ public abstract class InjectTest extends AbstractGremlinProcessTest {
         public Traversal<Vertex, String> get_g_VX1X_injectXg_VX4XX_out_name(final Object v1Id, final Object v4Id) {
             return g.V(v1Id).inject(g.V(v4Id).next()).out().values("name");
         }
+
+        @Override
+        public Traversal<Integer, Integer> get_g_injectXnull_1_3_nullX() {
+            return g.inject(null, 1, 3, null);
+        }
     }
 }
diff --git a/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/decoration/TranslationStrategy.java b/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/decoration/TranslationStrategy.java
index d2d63b2..c8451bb 100644
--- a/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/decoration/TranslationStrategy.java
+++ b/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/decoration/TranslationStrategy.java
@@ -134,7 +134,9 @@ public final class TranslationStrategy extends AbstractTraversalStrategy<Travers
             final Object[] newArgs = new Object[args.length];
 
             for (int i = 0; i < args.length; i++) {
-                if (args[i].equals("knows"))
+                if (args[i] == null)
+                    newArgs[i] = null;
+                else if (args[i].equals("knows"))
                     newArgs[i] = new Bytecode.Binding<>("a", "knows");
                 else if (args[i].equals("created"))
                     newArgs[i] = new Bytecode.Binding<>("b", "created");
diff --git a/tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/io/graphson/AbstractTinkerGraphGraphSONTranslatorProvider.java b/tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/io/graphson/AbstractTinkerGraphGraphSONTranslatorProvider.java
index 4d4ee00..7f4ebe8 100644
--- a/tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/io/graphson/AbstractTinkerGraphGraphSONTranslatorProvider.java
+++ b/tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/io/graphson/AbstractTinkerGraphGraphSONTranslatorProvider.java
@@ -213,10 +213,6 @@ import org.apache.tinkerpop.gremlin.tinkergraph.process.computer.TinkerGraphComp
         method = "shouldNeverPropagateANoBulkTraverser",
         reason = "Reason requires investigation")
 @Graph.OptOut(
-        test = "org.apache.tinkerpop.gremlin.process.traversal.CoreTraversalTest",
-        method = "shouldNeverPropagateANullValuedTraverser",
-        reason = "Reason requires investigation")
-@Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.ReadTest",
         method = "*",
         reason = "read and write tests don't translate locally well because of calling iterate() inside read()/write() add a none()")
diff --git a/tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/io/gryo/TinkerGraphGryoTranslatorProvider.java b/tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/io/gryo/TinkerGraphGryoTranslatorProvider.java
index d6d93a0..0d30df9 100644
--- a/tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/io/gryo/TinkerGraphGryoTranslatorProvider.java
+++ b/tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/io/gryo/TinkerGraphGryoTranslatorProvider.java
@@ -209,10 +209,6 @@ import org.apache.tinkerpop.gremlin.tinkergraph.TinkerGraphProvider;
         method = "shouldNeverPropagateANoBulkTraverser",
         reason = "Reason requires investigation")
 @Graph.OptOut(
-        test = "org.apache.tinkerpop.gremlin.process.traversal.CoreTraversalTest",
-        method = "shouldNeverPropagateANullValuedTraverser",
-        reason = "Reason requires investigation")
-@Graph.OptOut(
         test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.ReadTest",
         method = "*",
         reason = "read and write tests don't translate locally well because of calling iterate() inside read()/write() add a none()")