Avoid reading type info from trees that are not being processed (#385)

src/checkers/inference/DefaultSlotManager.java

@@ -1,8 +1,10 @@
 package checkers.inference;
 
 import checkers.inference.util.SlotDefaultTypeResolver;
+import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.CompilationUnitTree;
 import com.sun.source.tree.Tree;
+import com.sun.source.util.TreePath;
 import com.sun.tools.javac.code.Symbol;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.checkerframework.common.basetype.BaseAnnotatedTypeFactory;
@@ -11,6 +13,7 @@
 import org.checkerframework.javacutil.AnnotationBuilder;
 import org.checkerframework.javacutil.AnnotationUtils;
 import org.checkerframework.javacutil.BugInCF;
+import org.checkerframework.javacutil.TreeUtils;
 import org.checkerframework.javacutil.TypeKindUtils;
 import org.checkerframework.javacutil.TypesUtils;
 
@@ -202,6 +205,25 @@ public int compare(Class<? extends Annotation> o1, Class<? extends Annotation> o
         return set;
     }
 
+    @Override
+    public void setTopLevelClass(ClassTree classTree) {
+        // If the top level has changed, we refresh our cache with the new scope.
+        defaultAnnotationsCache.clear();
+
+        Map<Tree, AnnotatedTypeMirror> defaultTypes = SlotDefaultTypeResolver.resolve(
+                classTree,
+                InferenceMain.getInstance().getRealTypeFactory()
+        );
+
+        // find default types in the current hierarchy and save them to the cache
+        for (Map.Entry<Tree, AnnotatedTypeMirror> entry : defaultTypes.entrySet()) {
+            defaultAnnotationsCache.put(
+                    entry.getKey(),
+                    entry.getValue().getAnnotationInHierarchy(this.realTop)
+            );
+        }
+    }
+
     /**
      * Returns the next unique variable id.  These id's are monotonically increasing.
      * @return the next variable id to be used in VariableCreation
@@ -347,25 +369,6 @@ public int getNumberOfSlots() {
         return nextId - 1;
     }
 
-    @Override
-    public void setRoot(CompilationUnitTree compilationUnit) {
-        this.defaultAnnotationsCache.clear();
-
-        BaseAnnotatedTypeFactory realTypeFactory = InferenceMain.getInstance().getRealTypeFactory();
-        Map<Tree, AnnotatedTypeMirror> defaultTypes = SlotDefaultTypeResolver.resolve(
-                compilationUnit,
-                realTypeFactory
-        );
-
-        for (Map.Entry<Tree, AnnotatedTypeMirror> entry : defaultTypes.entrySet()) {
-            // find default types in the current hierarchy and save them to the cache
-            this.defaultAnnotationsCache.put(
-                    entry.getKey(),
-                    entry.getValue().getAnnotationInHierarchy(this.realTop)
-            );
-        }
-    }
-
     @Override
     public SourceVariableSlot createSourceVariableSlot(AnnotationLocation location, TypeMirror type) {
         AnnotationMirror defaultAnnotation = null;
@@ -424,13 +427,20 @@ public SourceVariableSlot createSourceVariableSlot(AnnotationLocation location,
             throw new BugInCF("Unable to find default annotation for location " + location);
         }
 
-        AnnotationMirror realAnnotation = null;
-        if (tree != null) {
-            realAnnotation = this.defaultAnnotationsCache.get(tree);
-            if (realAnnotation == null) {
-                // If its default type can't be found in the cache, we can
-                // fallback to the simplest method.
-                realAnnotation = realTypeFactory.getAnnotatedType(tree).getAnnotationInHierarchy(this.realTop);
+        AnnotationMirror realAnnotation = defaultAnnotationsCache.get(tree);
+        if (tree != null && realAnnotation == null) {
+            // If its default type can't be found in the cache, we can
+            // fallback to the simplest method.
+            // TODO: If the tree is not under the current top-level tree
+            //  that's being processed, the type factory may crash due
+            //  to lack of information. We may want to investigate if
+            //  this issue ever happens.
+            if (TreeUtils.isTypeTree(tree)) {
+                realAnnotation = realTypeFactory.getAnnotatedTypeFromTypeTree(tree)
+                        .getAnnotationInHierarchy(this.realTop);
+            } else {
+                realAnnotation = realTypeFactory.getAnnotatedType(tree)
+                        .getAnnotationInHierarchy(this.realTop);
             }
         }
         return realAnnotation;

src/checkers/inference/InferenceAnnotatedTypeFactory.java

@@ -2,6 +2,7 @@
 
 import checkers.inference.model.ConstantSlot;
 import checkers.inference.model.Slot;
+import com.sun.source.util.TreePath;
 import org.checkerframework.common.basetype.BaseAnnotatedTypeFactory;
 import org.checkerframework.framework.flow.CFAbstractAnalysis;
 import org.checkerframework.framework.flow.CFAnalysis;
@@ -536,7 +537,6 @@ public void addComputedTypeAnnotations(final Element element, final AnnotatedTyp
                 treeAnnotator.visit(declaration, type);
             } else {
                 bytecodeTypeAnnotator.annotate(element, type);
-
             }
         }
     }
@@ -550,7 +550,6 @@ public void setRoot(final CompilationUnitTree root) {
         compilationUnitsHandled += 1;
         this.realTypeFactory.setRoot( root );
         this.variableAnnotator.clearTreeInfo();
-        this.slotManager.setRoot(root);
         super.setRoot(root);
     }
 

src/checkers/inference/InferenceChecker.java

@@ -1,7 +1,5 @@
 package checkers.inference;
 
-import java.util.Properties;
-
 import org.checkerframework.common.basetype.BaseTypeChecker;
 import org.checkerframework.common.basetype.BaseTypeVisitor;
 
@@ -23,13 +21,4 @@ public void initChecker() {
     protected BaseTypeVisitor<?> createSourceVisitor() {
         return null;
     }
-
-    @Override
-    public Properties getMessagesProperties() {
-        // Add the messages.properties file defined in the same location as
-        // InferenceChecker
-        Properties messages = super.getMessagesProperties();
-        messages.putAll(getProperties(this.getClass(), MSGS_FILE, true));
-        return messages;
-    }
 }

src/checkers/inference/InferenceVisitor.java

@@ -1,5 +1,7 @@
 package checkers.inference;
 
+import com.sun.source.tree.ClassTree;
+import com.sun.source.util.TreePath;
 import org.checkerframework.checker.compilermsgs.qual.CompilerMessageKey;
 import org.checkerframework.common.basetype.BaseAnnotatedTypeFactory;
 import org.checkerframework.common.basetype.BaseTypeVisitor;
@@ -61,7 +63,7 @@
  *  That is, the methods from BaseTypeVisiotr should be migrated here and InferenceVisitor
  *  should replace it in the Visitor hierarchy.
  */
-// TODO(Zhiping): new logics from BaseTypeVisiotr should be migrated here
+// TODO(Zhiping): new logics from BaseTypeVisitor should be migrated here
 public class InferenceVisitor<Checker extends InferenceChecker,
         Factory extends BaseAnnotatedTypeFactory>
         extends BaseTypeVisitor<Factory> {
@@ -90,6 +92,15 @@ protected Factory createTypeFactory() {
         return (Factory)((BaseInferrableChecker)checker).getTypeFactory();
     }
 
+    @Override
+    public void visit(TreePath path) {
+        if (infer) {
+            final SlotManager slotManager = InferenceMain.getInstance().getSlotManager();
+            slotManager.setTopLevelClass((ClassTree) path.getLeaf());
+        }
+        super.visit(path);
+    }
+
     public void doesNotContain(AnnotatedTypeMirror ty, AnnotationMirror mod, String msgkey, Tree node) {
         doesNotContain(ty, new AnnotationMirror[] {mod}, msgkey, node);
     }

src/checkers/inference/SlotManager.java

@@ -1,6 +1,7 @@
 package checkers.inference;
 
 import checkers.inference.model.LubVariableSlot;
+import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.CompilationUnitTree;
 import org.checkerframework.framework.type.AnnotatedTypeMirror;
 
@@ -221,10 +222,13 @@ ArithmeticVariableSlot createArithmeticVariableSlot(
     List<ConstantSlot> getConstantSlots();
 
     /**
-     * Informs this manager that we are working on a new file, so
-     * it can preprocess and cache useful information.
+     * This method informs slot manager of the current top level class tree that's being type processed.
+     * Slot manager can then preprocess this information by clearing caches, resolving slot default
+     * types, etc.
      *
-     * @param compilationUnit the current compilation tree
+     * Note that trees that are not within this tree may be missing some information
+     * (in the JCTree implementation), and this is because they are either not fully
+     * initialized or being garbage-recycled.
      */
-    void setRoot(CompilationUnitTree compilationUnit);
+    void setTopLevelClass(ClassTree classTree);
 }

src/checkers/inference/util/SlotDefaultTypeResolver.java

@@ -3,7 +3,6 @@
 import com.sun.source.tree.AnnotatedTypeTree;
 import com.sun.source.tree.ArrayTypeTree;
 import com.sun.source.tree.ClassTree;
-import com.sun.source.tree.CompilationUnitTree;
 import com.sun.source.tree.ParameterizedTypeTree;
 import com.sun.source.tree.PrimitiveTypeTree;
 import com.sun.source.tree.Tree;
@@ -38,11 +37,11 @@
 public class SlotDefaultTypeResolver {
 
     public static Map<Tree, AnnotatedTypeMirror> resolve(
-            CompilationUnitTree root,
+            ClassTree classTree,
             BaseAnnotatedTypeFactory realTypeFactory
     ) {
         DefaultTypeFinder finder = new DefaultTypeFinder(realTypeFactory);
-        finder.scan(root, null);
+        finder.scan(classTree, null);
 
         return finder.defaultTypes;
     }
@@ -89,6 +88,9 @@ private AnnotatedTypeMirror getDefaultTypeFor(Tree tree) {
 
         @Override
         public Void visitClass(ClassTree tree, Void unused) {
+            // stores the default type of the class tree
+            getDefaultTypeFor(tree);
+
             Tree ext = tree.getExtendsClause();
             if (ext != null) {
                 defaultTypes.put(ext, realTypeFactory.getTypeOfExtendsImplements(ext));