Infinite recursion prevented on cyclic class hierarchies

compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/LazyClassDescriptor.java

@@ -22,6 +22,7 @@ import com.google.common.collect.Collections2;
 import com.google.common.collect.Lists;
 import com.intellij.openapi.util.Computable;
 import com.intellij.psi.PsiElement;
+import com.intellij.util.Consumer;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.lang.descriptors.*;
@@ -389,7 +390,8 @@ public class LazyClassDescriptor extends ClassDescriptorBase implements LazyDesc
     }
 
     private class LazyClassTypeConstructor implements LazyDescriptor, TypeConstructor {
-        private final LazyValue<Collection<JetType>> supertypes = resolveSession.getStorageManager().createLazyValue(new Computable<Collection<JetType>>() {
+        private final LazyValue<Collection<JetType>> supertypes = resolveSession.getStorageManager().createLazyValueWithPostCompute(
+                new Computable<Collection<JetType>>() {
                     @Override
                     public Collection<JetType> compute() {
                         if (resolveSession.isClassSpecial(DescriptorUtils.getFQName(LazyClassDescriptor.this))) {
@@ -405,14 +407,19 @@ public class LazyClassDescriptor extends ClassDescriptorBase implements LazyDesc
                                         .resolveSupertypes(getScopeForClassHeaderResolution(),
                                                            LazyClassDescriptor.this, classOrObject,
                                                            resolveSession.getTrace());
-                        List<JetType> validSupertypes = Lists.newArrayList(Collections2.filter(allSupertypes, VALID_SUPERTYPE));
 
-                        findAndDisconnectLoopsInTypeHierarchy(validSupertypes);
+                                return Lists.newArrayList(Collections2.filter(allSupertypes, VALID_SUPERTYPE));
-                        return validSupertypes;
                             }
                         }
                     }
+                },
+                new Consumer<Collection<JetType>>() {
+                    @Override
+                    public void consume(@NotNull Collection<JetType> supertypes) {
+                        findAndDisconnectLoopsInTypeHierarchy(supertypes);
+                    }
                 });
+
         private final LazyValue<List<TypeParameterDescriptor>> parameters = resolveSession.getStorageManager().createLazyValue(new Computable<List<TypeParameterDescriptor>>() {
             @Override
             public List<TypeParameterDescriptor> compute() {
@@ -440,7 +447,7 @@ public class LazyClassDescriptor extends ClassDescriptorBase implements LazyDesc
             return supertypes.get();
         }
 
-        private void findAndDisconnectLoopsInTypeHierarchy(List<JetType> supertypes) {
+        private void findAndDisconnectLoopsInTypeHierarchy(Collection<JetType> supertypes) {
             for (Iterator<JetType> iterator = supertypes.iterator(); iterator.hasNext(); ) {
                 JetType supertype = iterator.next();
                 if (isReachable(supertype.getConstructor(), this, new HashSet<TypeConstructor>())) {

compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/LockBasedStorageManager.java

@@ -17,6 +17,7 @@
 package org.jetbrains.jet.lang.resolve.lazy;
 
 import com.intellij.openapi.util.Computable;
+import com.intellij.util.Consumer;
 import com.intellij.util.Function;
 import com.intellij.util.containers.ConcurrentWeakValueHashMap;
 import org.jetbrains.annotations.NotNull;
@@ -106,12 +107,37 @@ public class LockBasedStorageManager implements StorageManager {
         return new LockBasedLazyValue<T>(lock, computable);
     }
 
+    @NotNull
+    @Override
+    public <T> LazyValue<T> createLazyValueWithPostCompute(@NotNull Computable<T> computable, @NotNull final Consumer<T> postCompute) {
+        return new LockBasedLazyValue<T>(lock, computable) {
+            @Override
+            protected void postCompute(@NotNull T value) {
+                postCompute.consume(value);
+            }
+        };
+    }
+
     @NotNull
     @Override
     public <T> LazyValue<T> createNullableLazyValue(@NotNull Computable<T> computable) {
         return new LockBasedNullableLazyValue<T>(lock, computable);
     }
 
+    @NotNull
+    @Override
+    public <T> LazyValue<T> createNullableLazyValueWithPostCompute(
+            @NotNull Computable<T> computable,
+            @NotNull final Consumer<T> postCompute
+    ) {
+        return new LockBasedNullableLazyValue<T>(lock, computable) {
+            @Override
+            protected void postCompute(@Nullable T value) {
+                postCompute.consume(value);
+            }
+        };
+    }
+
     @NotNull
     @Override
     public BindingTrace createSafeTrace(@NotNull BindingTrace originalTrace) {
@@ -145,10 +171,15 @@ public class LockBasedStorageManager implements StorageManager {
                 if (_value == null) {
                     _value = computable.compute();
                     value = _value;
+                    postCompute(_value);
                 }
                 return _value;
             }
         }
+
+        protected void postCompute(@NotNull T value) {
+            // Doing something in post-compute helps prevent infinite recursion
+        }
     }
 
     private static class LockBasedNullableLazyValue<T> implements LazyValue<T> {
@@ -183,11 +214,17 @@ public class LockBasedStorageManager implements StorageManager {
                     value = _value;
                     computed = true;
 
+                    postCompute(_value);
+
                     return _value;
                 }
                 return value;
             }
         }
+
+        protected void postCompute(@Nullable T value) {
+            // Doing something in post-compute helps prevent infinite recursion
+        }
     }
 
     private static class LockProtectedTrace implements BindingTrace {

compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/StorageManager.java

@@ -17,6 +17,7 @@
 package org.jetbrains.jet.lang.resolve.lazy;
 
 import com.intellij.openapi.util.Computable;
+import com.intellij.util.Consumer;
 import com.intellij.util.Function;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.jet.lang.resolve.BindingTrace;
@@ -35,9 +36,23 @@ public interface StorageManager {
     @NotNull
     <T> LazyValue<T> createLazyValue(@NotNull Computable<T> computable);
 
+    /**
+     * {@code postCompute} is called after the value is computed, but before any other thread sees it (the current thread may
+     * see it in between)
+     */
+    @NotNull
+    <T> LazyValue<T> createLazyValueWithPostCompute(@NotNull Computable<T> computable, @NotNull Consumer<T> postCompute);
+
     @NotNull
     <T> LazyValue<T> createNullableLazyValue(@NotNull Computable<T> computable);
 
+    /**
+     * {@code postCompute} is called after the value is computed, but before any other thread sees it (the current thread may
+     * see it in between)
+     */
+    @NotNull
+    <T> LazyValue<T> createNullableLazyValueWithPostCompute(@NotNull Computable<T> computable, @NotNull Consumer<T> postCompute);
+
     @NotNull
     BindingTrace createSafeTrace(@NotNull BindingTrace originalTrace);
 

idea/testData/checker/trivialHierarchyLoop.kt

@@ -0,0 +1,3 @@
+class A : <error>A</error>() {}
+
+val x : Int = <error>A()</error>

idea/tests/org/jetbrains/jet/checkers/JetPsiCheckerTestGenerated.java

@@ -243,6 +243,11 @@ public class JetPsiCheckerTestGenerated extends AbstractJetPsiCheckerTest {
             doTest("idea/testData/checker/TraitSupertypeList.kt");
         }
         
+        @TestMetadata("trivialHierarchyLoop.kt")
+        public void testTrivialHierarchyLoop() throws Exception {
+            doTest("idea/testData/checker/trivialHierarchyLoop.kt");
+        }
+        
         @TestMetadata("UnreachableCode.kt")
         public void testUnreachableCode() throws Exception {
             doTest("idea/testData/checker/UnreachableCode.kt");