Show null children (shown per default)

dumpAst/src/main/jastadd/DumpAst.relast

 DumpAst ::= DumpNode* <PackageName> BuildConfig PrintConfig ;
 rel DumpAst.RootNode -> DumpNode ;
 
-BuildConfig ::= GlobalPatternCollection:PatternCollection StyleInformation ExcludeTypePattern:TypePatternCollectionMapping* IncludeTypePattern:TypePatternCollectionMapping* <TypeIgnorePattern> <IncludeEmptyString:boolean> <Debug:boolean>;
+BuildConfig ::= StyleInformation GlobalPatternCollection:PatternCollection
+ ExcludeTypePattern:TypePatternCollectionMapping* IncludeTypePattern:TypePatternCollectionMapping*
+ <TypeIgnorePattern> <IncludeEmptyString:boolean> <ExcludeNullNodes:boolean> <Debug:boolean>;
 TypePatternCollectionMapping ::= <TypeRegex> PatternCollection ;
 PatternCollection ::= <TokenPattern> <ChildPattern> <RelationPattern> <AttributePattern> <NonterminalAttributePattern> ;
 StyleInformation ::= <NameMethod:StyleMethod> <BackgroundColorMethod:StyleMethod> <TextColorMethod:StyleMethod>;
@@ -9,7 +11,9 @@ StyleInformation ::= <NameMethod:StyleMethod> <BackgroundColorMethod:StyleMethod
 PrintConfig ::= <Scale:double> <Version> <OrderChildren:boolean> Header* ;
 Header ::= <Value> ;
 
-DumpNode ::= <Name> <Label> <BackgroundColor> <TextColor> <Object:Object> <Invisible:boolean> DumpChildNode* DumpToken* DumpRelation* /InvisiblePath/ ;
+DumpNode ::=  DumpChildNode* DumpToken* DumpRelation*
+ <Name> <Label> <BackgroundColor> <TextColor> <Object:Object> <Invisible:boolean>
+ /InvisiblePath/ ;
 InnerDumpNode ;
 rel InnerDumpNode.DumpNode <-> DumpNode.ContainerOfInner ;
 

dumpAst/src/main/jastadd/GenerationBackend.jadd

@@ -26,11 +26,23 @@ aspect GenerationBackend {
   }
   protected DumpNode DumpAst.transform(TransformationTransferInformation tti, Object obj, Source source)
       throws java.lang.reflect.InvocationTargetException, IllegalAccessException, NoSuchMethodException {
-    if (obj == null) {
+    return transform(tti, obj, source, false);
+  }
+  protected DumpNode DumpAst.transform(
+      TransformationTransferInformation tti, Object obj, Source source, boolean allowNullObj)
+      throws java.lang.reflect.InvocationTargetException, IllegalAccessException, NoSuchMethodException {
+    if (obj == null && !allowNullObj) {
       return null;
     }
-    DumpNode node = tti.transformed.get(obj);
-    String objClassName = obj.getClass().getSimpleName();
+    DumpNode node;
+    String objClassName;
+    if (obj == null) {
+      node = null;
+      objClassName = "null";
+    } else {
+      node = tti.transformed.get(obj);
+      objClassName = obj.getClass().getSimpleName();
+    }
     if (node != null) {
       if (source == Source.RELATION) {
         return node;
@@ -47,9 +59,7 @@ aspect GenerationBackend {
     if (!node.isAstNode()) {
       return node;
     }
-    node.setLabel(getBuildConfig().getStyleInformation().getNameMethod().get(obj));
-    node.setBackgroundColor(getBuildConfig().getStyleInformation().getBackgroundColorMethod().get(obj));
-    node.setTextColor(getBuildConfig().getStyleInformation().getTextColorMethod().get(obj));
+    applyStyle(node);
     // do not process node further if coming from a relation
     if (source == Source.RELATION) {
       tti.relationTargetsUnprocessed.put(node, true);
@@ -58,13 +68,17 @@ aspect GenerationBackend {
     if (source == Source.INVISIBLE_PARENT || !isTypeEnabled(objClassName)) {
       node.setInvisible(true);
     }
+    if (obj == null) {
+      // for a null object, we do not need any further analysis
+      return node;
+    }
     final ClassAnalysisResult car = analyzeClass(obj.getClass());
     // -- singleChild --
     for (SingleChildMethod singleChildMethod : car.singleChildMethods()) {
       Object target = singleChildMethod.getMethod().invoke(obj);
       String childName = singleChildMethod.getName();
-      DumpNode targetNode = transform(tti, target, nextSource(source, !isChildEnabled(objClassName, childName)));
-      if (target != null && targetNode != null) {
+      DumpNode targetNode = transform(tti, target, nextSource(source, !isChildEnabled(objClassName, childName)), !getBuildConfig().getExcludeNullNodes());
+      if (targetNode != null) {
         DumpNormalChildNode normalChild = new DumpNormalChildNode();
         normalChild.setName(childName);
         normalChild.setDumpNode(targetNode);
@@ -143,6 +157,13 @@ aspect GenerationBackend {
     return node;
   }
 
+  private void DumpAst.applyStyle(DumpNode node) {
+    Object obj = node.getObject();
+    node.setLabel(getBuildConfig().getStyleInformation().getNameMethod().get(obj));
+    node.setBackgroundColor(getBuildConfig().getStyleInformation().getBackgroundColorMethod().get(obj));
+    node.setTextColor(getBuildConfig().getStyleInformation().getTextColorMethod().get(obj));
+  }
+
   private Source DumpAst.nextSource(Source currentSource, boolean shouldBeInvisible) {
     return currentSource == Source.INVISIBLE_PARENT ? Source.INVISIBLE_PARENT :
         (shouldBeInvisible ? Source.INVISIBLE_PARENT : Source.PARENT);
@@ -415,6 +436,10 @@ aspect GenerationBackend {
 
   // --- isAstNode ---
   syn boolean DumpNode.isAstNode() {
+    if (getObject() == null) {
+      // this is only possible for normal child nodes, and they are ast nodes
+      return true;
+    }
     Class<?> clazz = getObject().getClass();
     for (java.lang.reflect.Method method : clazz.getMethods()) {
       if ("init$Children".equals(method.getName()) && method.getParameterCount() == 0) {
@@ -462,7 +487,6 @@ aspect GenerationBackend {
     }
   }
 
-
   // --- myChildren ---
   syn java.util.List<DumpNode> DumpNode.myChildren() {
     java.util.List<DumpNode> result = new java.util.ArrayList<>();
@@ -579,7 +603,7 @@ aspect GenerationBackend {
 
   static StyleInformation StyleInformation.createDefault() {
     StyleInformation result = new StyleInformation();
-    result.setNameMethod(n -> n.getClass().getSimpleName() + "@" + Integer.toHexString(n.hashCode()));
+    result.setNameMethod(n -> n == null ? "null" : n.getClass().getSimpleName() + "@" + Integer.toHexString(n.hashCode()));
     result.setBackgroundColorMethod(n -> "");
     result.setTextColorMethod(n -> "");
     return result;

dumpAst/src/main/jastadd/GenerationFrontend.jadd

@@ -308,6 +308,16 @@ public class DumpBuilder {
       }
     }
 
+    public DumpBuilder excludeNullNodes() {
+      buildConfig.setExcludeNullNodes(true);
+      return this;
+    }
+
+    public DumpBuilder includeNullNodes() {
+      buildConfig.setExcludeNullNodes(false);
+      return this;
+    }
+
     public DumpBuilder customPreamble(String option) {
       printConfig.addHeader(new Header(option));
       return this;

testDumper/src/test/java/de/tudresden/inf/st/jastadd/testDumper/TestDumperMain.java

@@ -35,7 +35,7 @@ public class TestDumperMain {
     builder.includeAttributes("simpleAttr")
         .orderChildren()
         .includeNonterminalAttributes("getCalculated")
-        .setNameMethod(n -> n.getClass().getSimpleName());
+        .setNameMethod(n -> n == null ? "null" : n.getClass().getSimpleName());
 
     System.out.println(">> PlantUml");
     DumpAst dumpAst = builder.build();

testDumper/src/test/java/de/tudresden/inf/st/jastadd/testDumper/TestSimple.java

@@ -31,9 +31,9 @@ public class TestSimple {
   @Test void testChildlessNonterminal() {
     Root root = createRoot(createA(A_NAME, a -> a.setD(new D())), null);
     List<DumpNode> nodes = TestUtils.dumpModel(root);
-    Optional<DumpNode> optionalCDumpNode = nodes.stream().filter(n -> n.getObject() instanceof D).findFirst();
-    assertTrue(optionalCDumpNode.isPresent());
-    assertTrue(optionalCDumpNode.get().isAstNode());
+    Optional<DumpNode> actualD = nodes.stream().filter(n -> n.getObject() instanceof D).findFirst();
+    assertTrue(actualD.isPresent());
+    assertTrue(actualD.get().isAstNode());
   }
 
   @Test
@@ -49,6 +49,22 @@ public class TestSimple {
     assertThatMapOf(normalChildren(actualRoot)).containsExactlyInAnyOrder(tuple("A", A_NAME));
   }
 
+  @Test
+  public void testOneNormalChildIncludeNullNodes() {
+    Root root = createRoot(createA(A_NAME), null);
+
+    List<DumpNode> nodes = TestUtils.dumpModel(root, DumpBuilder::includeNullNodes);
+    assertThat(nodes).flatExtracting(NAME_EXTRACTOR).containsExactlyInAnyOrder(
+        ROOT_NAME, A_NAME, null, null, null, null);
+    DumpNode actualRoot = TestUtils.findByName(nodes, ROOT_NAME);
+    assertEquals(1, actualRoot.getNumDumpToken());
+    assertEquals(2, actualRoot.getNumDumpChildNode());
+    assertEquals(0, actualRoot.getNumDumpRelation());
+
+    DumpNode actualA = TestUtils.findByName(nodes, A_NAME);
+    assertEquals(3, actualA.getNumDumpChildNode());
+  }
+
   @Test
   public void testListChildren() {
     Root root = createRoot(null, null, createB(B1_NAME), createB(B2_NAME), createB(B3_NAME));

testDumper/src/test/java/de/tudresden/inf/st/jastadd/testDumper/TestUtils.java

@@ -156,6 +156,7 @@ public class TestUtils {
 
   public static List<DumpNode> dumpModel(Object target, Consumer<DumpBuilder> options) {
     ExposingDumpBuilder builder = new ExposingDumpBuilder(target);
+    builder.excludeNullNodes();
     options.accept(builder);
     DumpAst dumpAst = builder.build();
     // let mustache run, but ignore result