Do not lookup expressions in closures when building signatures

#KT-2764 Fixed
(EA-38857)

compiler/backend/src/org/jetbrains/jet/codegen/ImplementationBodyCodegen.java

@@ -625,7 +625,9 @@ public class ImplementationBodyCodegen extends ClassBodyCodegen {
 
         final ConstructorContext constructorContext = context.intoConstructor(constructorDescriptor);
 
-        lookupConstructorExpressionsInClosureIfPresent(constructorContext);
+        if (state.getClassBuilderMode() == ClassBuilderMode.FULL) {
+            lookupConstructorExpressionsInClosureIfPresent(constructorContext);
+        }
 
         MutableClosure closure = context.closure;
         boolean hasThis0 = closure != null && closure.getCaptureThis() != null;

idea/testData/javaFacade/kt2764.kt

@@ -0,0 +1,8 @@
+fun main(args: Array<String>) {
+}
+
+class <caret>Foo(val b: Int) {
+    {
+        this.b
+    }
+}

idea/tests/org/jetbrains/jet/plugin/javaFacade/JetJavaFacadeTest.java

@@ -74,6 +74,10 @@ public class JetJavaFacadeTest extends LightCodeInsightFixtureTestCase {
         doTestWrapMethod(true);
     }
 
+    public void testKt2764() {
+        doTestWrapClass();
+    }
+
     public void testInnerClass() throws Exception {
         myFixture.configureByFile(getTestName(true) + ".kt");
 
@@ -144,10 +148,31 @@ public class JetJavaFacadeTest extends LightCodeInsightFixtureTestCase {
         if (shouldBeWrapped) {
             assertNotNull(String.format("Failed to wrap jetFunction '%s' to method", jetFunction.getText()), psiMethod);
             assertInstanceOf(psiMethod, PsiCompiledElement.class);
-            assertEquals("Invalid original element for generated method", ((PsiCompiledElement)psiMethod).getMirror(), jetFunction);
+            assertEquals("Invalid original element for generated method", ((PsiCompiledElement) psiMethod).getMirror(), jetFunction);
         }
         else {
             assertNull("There should be no wrapper for given method", psiMethod);
         }
     }
+
+    private void doTestWrapClass() {
+        myFixture.configureByFile(getTestName(true) + ".kt");
+
+        int offset = myFixture.getEditor().getCaretModel().getOffset();
+        PsiElement elementAt = myFixture.getFile().findElementAt(offset);
+
+        assertNotNull("Caret should be set for tested file", elementAt);
+
+        JetClass jetClass = PsiTreeUtil.getParentOfType(elementAt, JetClass.class);
+        assertNotNull("Caret should be placed to class definition", jetClass);
+
+        // Should not fail!
+        JetLightClass lightClass = JetLightClass.wrapDelegate(jetClass);
+
+        assertNotNull(String.format("Failed to wrap jetClass '%s' to class", jetClass.getText()), lightClass);
+
+        // This invokes codegen with ClassBuilderMode = SIGNATURES
+        // No exception/error should happen here
+        lightClass.getDelegate();
+    }
 }