KT-2632 Check multi-declaraions in for-loops

#KT-2632 Fixed

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

@@ -267,6 +267,14 @@ public class ControlStructureTypingVisitor extends ExpressionTypingVisitor {
 
             loopScope.addVariableDescriptor(variableDescriptor);
         }
+        else {
+            JetMultiDeclaration multiParameter = expression.getMultiParameter();
+            if (multiParameter != null && loopRange != null) {
+                JetType elementType = expectedParameterType == null ? ErrorUtils.createErrorType("Loop range has no type") : expectedParameterType;
+                TransientReceiver iteratorNextAsReceiver = new TransientReceiver(elementType);
+                ExpressionTypingUtils.defineLocalVariablesFromMultiDeclaration(loopScope, multiParameter, iteratorNextAsReceiver, loopRange, context);
+            }
+        }
 
         JetExpression body = expression.getBody();
         if (body != null) {

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/DoubleDeclForLoop.kt

@@ -0,0 +1,14 @@
+class A {
+    fun component1() = 1
+    fun component2() = 1
+}
+
+class C {
+    fun iterator(): Iterator<A> = null!!
+}
+
+fun test() {
+    for ((x, y) in C()) {
+
+    }
+}

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/FolLoopTypeComponentTypeMismatch.kt

@@ -0,0 +1,14 @@
+class A {
+    fun component1() = 1
+    fun component2() = 1.0
+}
+
+class C {
+    fun iterator(): Iterator<A> = null!!
+}
+
+fun test() {
+    for ((x: Double, y: Int) in <!COMPONENT_FUNCTION_RETURN_TYPE_MISMATCH, COMPONENT_FUNCTION_RETURN_TYPE_MISMATCH!>C()<!>) {
+
+    }
+}

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/ForLoopComponentFunctionAmbiguity.kt

@@ -0,0 +1,15 @@
+class A {
+    <!CONFLICTING_OVERLOADS!>fun component1()<!> = 1
+    <!CONFLICTING_OVERLOADS!>fun component1()<!> = 1
+    fun component2() = 1
+}
+
+class C {
+    fun iterator(): Iterator<A> = null!!
+}
+
+fun test() {
+    for ((x, y) in <!COMPONENT_FUNCTION_AMBIGUITY!>C()<!>) {
+
+    }
+}

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/ForLoopComponentFunctionMissing.kt

@@ -0,0 +1,13 @@
+class A {
+    fun component1() = 1
+}
+
+class C {
+    fun iterator(): Iterator<A> = null!!
+}
+
+fun test() {
+    for ((x, y) in <!COMPONENT_FUNCTION_MISSING!>C()<!>) {
+
+    }
+}

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/ForLoopWithExtensions.kt

@@ -0,0 +1,14 @@
+class A {
+}
+fun A.component1() = 1
+fun A.component2() = 1
+
+class C {
+    fun iterator(): Iterator<A> = null!!
+}
+
+fun test() {
+    for ((x, y) in C()) {
+
+    }
+}

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/ForWithExplicitTypes.kt

@@ -0,0 +1,14 @@
+class A {
+    fun component1() = 1
+    fun component2() = 1.0
+}
+
+class C {
+    fun iterator(): Iterator<A> = null!!
+}
+
+fun test() {
+    for ((x: Int, y: Double) in C()) {
+
+    }
+}

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/RedeclarationInForLoop.kt

@@ -0,0 +1,14 @@
+class A {
+    fun component1() = 1
+    fun component2() = 1
+}
+
+class C {
+    fun iterator(): Iterator<A> = null!!
+}
+
+fun test() {
+    for ((<!REDECLARATION!>x<!>, <!REDECLARATION!>x<!>) in C()) {
+
+    }
+}

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/SingleDeclForLoop.kt

@@ -0,0 +1,13 @@
+class A {
+    fun component1() = 1
+}
+
+class C {
+    fun iterator(): Iterator<A> = null!!
+}
+
+fun test() {
+    for ((x) in C()) {
+
+    }
+}

compiler/tests/org/jetbrains/jet/checkers/JetDiagnosticsTestGenerated.java

@@ -1113,6 +1113,60 @@ public class JetDiagnosticsTestGenerated extends AbstractDiagnosticsTestWithEage
                 doTest("compiler/testData/diagnostics/tests/declarationChecks/RedeclarationsInMultiDecl.kt");
             }
             
+            @TestMetadata("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations")
+            public static class MultiDeclarations extends AbstractDiagnosticsTestWithEagerResolve {
+                public void testAllFilesPresentInMultiDeclarations() throws Exception {
+                    JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), "org.jetbrains.jet.checkers.AbstractDiagnosticsTestWithEagerResolve", new File("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations"), "kt", false);
+                }
+                
+                @TestMetadata("DoubleDeclForLoop.kt")
+                public void testDoubleDeclForLoop() throws Exception {
+                    doTest("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/DoubleDeclForLoop.kt");
+                }
+                
+                @TestMetadata("FolLoopTypeComponentTypeMismatch.kt")
+                public void testFolLoopTypeComponentTypeMismatch() throws Exception {
+                    doTest("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/FolLoopTypeComponentTypeMismatch.kt");
+                }
+                
+                @TestMetadata("ForLoopComponentFunctionAmbiguity.kt")
+                public void testForLoopComponentFunctionAmbiguity() throws Exception {
+                    doTest("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/ForLoopComponentFunctionAmbiguity.kt");
+                }
+                
+                @TestMetadata("ForLoopComponentFunctionMissing.kt")
+                public void testForLoopComponentFunctionMissing() throws Exception {
+                    doTest("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/ForLoopComponentFunctionMissing.kt");
+                }
+                
+                @TestMetadata("ForLoopWithExtensions.kt")
+                public void testForLoopWithExtensions() throws Exception {
+                    doTest("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/ForLoopWithExtensions.kt");
+                }
+                
+                @TestMetadata("ForWithExplicitTypes.kt")
+                public void testForWithExplicitTypes() throws Exception {
+                    doTest("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/ForWithExplicitTypes.kt");
+                }
+                
+                @TestMetadata("RedeclarationInForLoop.kt")
+                public void testRedeclarationInForLoop() throws Exception {
+                    doTest("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/RedeclarationInForLoop.kt");
+                }
+                
+                @TestMetadata("SingleDeclForLoop.kt")
+                public void testSingleDeclForLoop() throws Exception {
+                    doTest("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/SingleDeclForLoop.kt");
+                }
+                
+            }
+            
+            public static Test innerSuite() {
+                TestSuite suite = new TestSuite("DeclarationChecks");
+                suite.addTestSuite(DeclarationChecks.class);
+                suite.addTestSuite(MultiDeclarations.class);
+                return suite;
+            }
         }
         
         @TestMetadata("compiler/testData/diagnostics/tests/extensions")
@@ -2972,7 +3026,7 @@ public class JetDiagnosticsTestGenerated extends AbstractDiagnosticsTestWithEage
             suite.addTestSuite(ControlStructures.class);
             suite.addTestSuite(DataFlow.class);
             suite.addTestSuite(DataFlowInfoTraversal.class);
-            suite.addTestSuite(DeclarationChecks.class);
+            suite.addTest(DeclarationChecks.innerSuite());
             suite.addTestSuite(Extensions.class);
             suite.addTestSuite(Generics.class);
             suite.addTest(IncompleteCode.innerSuite());