KT-1041 Add check that thrown/catched expression is of Throwable type

compiler/frontend/src/jet/Library.jet

@@ -59,3 +59,9 @@ class String() : Comparable<String>, CharSequence {
 
   fun equals(other : Any?) : Boolean
 }
+
+class Throwable(message : String? = null, cause: Throwable? = null) {
+    fun getMessage() : String?
+    fun getCause() : Throwable?
+    fun printStackTrace() : Unit
+}

compiler/frontend/src/org/jetbrains/jet/lang/types/JetStandardLibrary.java

@@ -72,14 +72,16 @@ public class JetStandardLibrary {
     private ClassDescriptor iterableClass;
     private ClassDescriptor comparableClass;
     private ClassDescriptor volatileClass;
+    private ClassDescriptor throwableClass;
 
     private JetType stringType;
     private JetType volatileType;
     private JetType nullableStringType;
     private JetType charSequenceType;
     private JetType nullableCharSequenceType;
-
     private JetType nullableTuple0Type;
+    private JetType throwableType;
+    private JetType nullableThrowableType;
 
     private JetType tuple0Type;
 
@@ -143,6 +145,7 @@ public class JetStandardLibrary {
             this.charSequenceClass = (ClassDescriptor) libraryScope.getClassifier("CharSequence");
             this.arrayClass = (ClassDescriptor) libraryScope.getClassifier("Array");
             this.volatileClass = (ClassDescriptor) libraryScope.getClassifier("volatile");
+            this.throwableClass = (ClassDescriptor) libraryScope.getClassifier("Throwable");            
 
             this.iterableClass = (ClassDescriptor) libraryScope.getClassifier("Iterable");
             this.comparableClass = (ClassDescriptor) libraryScope.getClassifier("Comparable");
@@ -153,6 +156,8 @@ public class JetStandardLibrary {
             this.nullableCharSequenceType = TypeUtils.makeNullable(charSequenceType);
             this.nullableStringType = TypeUtils.makeNullable(stringType);
             this.volatileType = new JetTypeImpl(getVolatile());
+            this.throwableType = new JetTypeImpl(getThrowable());
+            this.nullableThrowableType = TypeUtils.makeNullable(throwableType);
 
             this.tuple0Type = new JetTypeImpl(JetStandardClasses.getTuple(0));
             this.nullableTuple0Type = TypeUtils.makeNullable(tuple0Type);
@@ -270,6 +275,12 @@ public class JetStandardLibrary {
         return comparableClass;
     }
 
+    @NotNull
+    public ClassDescriptor getThrowable() {
+        initStdClasses();
+        return throwableClass;
+    }
+    
     public Set<FunctionDescriptor> getTypeInfoFunctions() {
         initStdClasses();
         return typeInfoFunction;
@@ -393,6 +404,17 @@ public class JetStandardLibrary {
         initStdClasses();
         return nullableCharSequenceType;
     }
+    
+    @NotNull
+    public JetType getThrowableType() {
+        initStdClasses();
+        return throwableType;
+    }
+
+    public JetType getNullableThrowableType() {
+        initStdClasses();
+        return nullableThrowableType;
+    }
 
     @NotNull
     public JetType getNullablePrimitiveJetType(PrimitiveType primitiveType) {

compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/ControlStructureTypingVisitor.java

@@ -400,6 +400,8 @@ public class ControlStructureTypingVisitor extends ExpressionTypingVisitor {
             JetExpression catchBody = catchClause.getCatchBody();
             if (catchParameter != null) {
                 VariableDescriptor variableDescriptor = context.getDescriptorResolver().resolveLocalVariableDescriptor(context.scope.getContainingDeclaration(), context.scope, catchParameter);
+                JetType throwableType = context.semanticServices.getStandardLibrary().getThrowable().getDefaultType();
+                DataFlowUtils.checkType(variableDescriptor.getOutType(), catchParameter, context.replaceExpectedType(throwableType));
                 if (catchBody != null) {
                     WritableScope catchScope = newWritableScopeImpl(context).setDebugName("Catch scope");
                     catchScope.addVariableDescriptor(variableDescriptor);
@@ -433,8 +435,8 @@ public class ControlStructureTypingVisitor extends ExpressionTypingVisitor {
     public JetType visitThrowExpression(JetThrowExpression expression, ExpressionTypingContext context) {
         JetExpression thrownExpression = expression.getThrownExpression();
         if (thrownExpression != null) {
-            JetType type = facade.getType(thrownExpression, context.replaceExpectedType(TypeUtils.NO_EXPECTED_TYPE).replaceScope(context.scope));
-            // TODO : check that it inherits Throwable
+            JetType throwableType = context.semanticServices.getStandardLibrary().getThrowable().getDefaultType();
+            facade.getType(thrownExpression, context.replaceExpectedType(throwableType).replaceScope(context.scope));
         }
         return DataFlowUtils.checkType(JetStandardClasses.getNothingType(), expression, context);
     }