Fix NPEs around unresolved attribute references

Fixes #84

Author: cirras

delphi-checks/src/main/java/au/com/integradev/delphi/checks/ForbiddenRoutineCheck.java

@@ -29,6 +29,7 @@
 import org.sonar.plugins.communitydelphi.api.check.DelphiCheck;
 import org.sonar.plugins.communitydelphi.api.check.DelphiCheckContext;
 import org.sonar.plugins.communitydelphi.api.check.RuleTemplate;
+import org.sonar.plugins.communitydelphi.api.symbol.NameOccurrence;
 import org.sonar.plugins.communitydelphi.api.symbol.declaration.NameDeclaration;
 import org.sonar.plugins.communitydelphi.api.symbol.declaration.RoutineNameDeclaration;
 import org.sonarsource.analyzer.commons.annotations.DeprecatedRuleKey;
@@ -70,10 +71,13 @@ public DelphiCheckContext visit(NameReferenceNode reference, DelphiCheckContext
 
   @Override
   public DelphiCheckContext visit(AttributeNode attribute, DelphiCheckContext context) {
-    NameDeclaration declaration = attribute.getConstructorNameOccurrence().getNameDeclaration();
-    if (declaration instanceof RoutineNameDeclaration
-        && routinesSet.contains(((RoutineNameDeclaration) declaration).fullyQualifiedName())) {
-      reportIssue(context, attribute.getNameReference().getIdentifier(), message);
+    NameOccurrence occurrence = attribute.getConstructorNameOccurrence();
+    if (occurrence != null) {
+      NameDeclaration declaration = occurrence.getNameDeclaration();
+      if (declaration instanceof RoutineNameDeclaration
+          && routinesSet.contains(((RoutineNameDeclaration) declaration).fullyQualifiedName())) {
+        reportIssue(context, attribute.getNameReference().getIdentifier(), message);
+      }
     }
     return super.visit(attribute, context);
   }

delphi-frontend/src/main/java/au/com/integradev/delphi/symbol/resolve/NameResolver.java

@@ -548,11 +548,15 @@ void readAttribute(AttributeNode node) {
     List<NameReferenceNode> references = node.getNameReference().flatten();
     NameReferenceNode lastReference = references.get(references.size() - 1);
 
+    var attributeNameOccurrence = (AttributeNameOccurrenceImpl) lastReference.getNameOccurrence();
+    if (attributeNameOccurrence == null) {
+      return;
+    }
+
     // Attributes are a shorthand for an invocation of a constructor named 'Create'
     SymbolicNode imaginaryConstructor = SymbolicNode.imaginary("Create", node.getScope());
     NameOccurrenceImpl occurrence = new NameOccurrenceImpl(imaginaryConstructor);
-    ((AttributeNameOccurrenceImpl) lastReference.getNameOccurrence())
-        .setImplicitConstructorNameOccurrence(occurrence);
+    attributeNameOccurrence.setImplicitConstructorNameOccurrence(occurrence);
 
     resolveNameReferenceOccurrence(occurrence, true);
 

delphi-frontend/src/main/java/au/com/integradev/delphi/type/factory/TypeFactoryImpl.java

@@ -36,13 +36,15 @@
 import java.util.stream.Collectors;
 import javax.annotation.Nullable;
 import org.sonar.plugins.communitydelphi.api.ast.AttributeListNode;
+import org.sonar.plugins.communitydelphi.api.ast.AttributeNode;
 import org.sonar.plugins.communitydelphi.api.ast.ClassHelperTypeNode;
 import org.sonar.plugins.communitydelphi.api.ast.DelphiNode;
 import org.sonar.plugins.communitydelphi.api.ast.GenericDefinitionNode.TypeParameter;
 import org.sonar.plugins.communitydelphi.api.ast.HelperTypeNode;
 import org.sonar.plugins.communitydelphi.api.ast.Node;
 import org.sonar.plugins.communitydelphi.api.ast.TypeDeclarationNode;
 import org.sonar.plugins.communitydelphi.api.ast.TypeNode;
+import org.sonar.plugins.communitydelphi.api.symbol.declaration.NameDeclaration;
 import org.sonar.plugins.communitydelphi.api.symbol.declaration.TypeNameDeclaration;
 import org.sonar.plugins.communitydelphi.api.symbol.declaration.TypedDeclaration;
 import org.sonar.plugins.communitydelphi.api.symbol.scope.DelphiScope;
@@ -68,7 +70,6 @@
 import org.sonar.plugins.communitydelphi.api.type.Type.StructType;
 import org.sonar.plugins.communitydelphi.api.type.Type.SubrangeType;
 import org.sonar.plugins.communitydelphi.api.type.TypeFactory;
-import org.sonar.plugins.communitydelphi.api.type.Typed;
 
 public class TypeFactoryImpl implements TypeFactory {
   private static final CompilerVersion VERSION_4 = CompilerVersion.fromVersionSymbol("VER120");
@@ -505,10 +506,21 @@ private static List<Type> getAttributeTypes(TypeDeclarationNode typeDeclaration)
     }
 
     return attributeList.getAttributes().stream()
-        .map(attribute -> attribute.getTypeNameOccurrence().getNameDeclaration())
-        .map(TypeNameDeclaration.class::cast)
-        .map(Typed::getType)
-        .collect(Collectors.toList());
+        .map(AttributeNode::getTypeNameOccurrence)
+        .map(
+            occurrence -> {
+              if (occurrence == null) {
+                return TypeFactory.unknownType();
+              }
+
+              NameDeclaration declaration = occurrence.getNameDeclaration();
+              if (!(declaration instanceof TypeNameDeclaration)) {
+                return TypeFactory.unknownType();
+              }
+
+              return ((TypeNameDeclaration) declaration).getType();
+            })
+        .collect(Collectors.toUnmodifiableList());
   }
 
   public HelperType helper(HelperTypeNode node) {

delphi-frontend/src/main/java/org/sonar/plugins/communitydelphi/api/ast/AttributeNode.java

@@ -18,14 +18,18 @@
  */
 package org.sonar.plugins.communitydelphi.api.ast;
 
+import javax.annotation.Nullable;
 import org.sonar.plugins.communitydelphi.api.symbol.NameOccurrence;
 
 public interface AttributeNode extends DelphiNode {
   NameReferenceNode getNameReference();
 
+  @Nullable
   NameOccurrence getTypeNameOccurrence();
 
+  @Nullable
   NameOccurrence getConstructorNameOccurrence();
 
+  @Nullable
   ArgumentListNode getArgumentList();
 }