GROOVY-8319: Improve smart type on list expressions (closes #602)

Author: avafanasiev

src/main/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java

@@ -873,6 +873,8 @@ private boolean typeCheckMultipleAssignmentAndContinue(Expression leftExpression
             if (!isAssignableTo(elemType, tupleType)) {
                 addStaticTypeError("Cannot assign value of type " + elemType.toString(false) + " to variable of type " + tupleType.toString(false), rightExpression);
                 return false; // avoids too many errors
+            } else {
+                storeType(tupleExpression, elemType);
             }
         }
 
@@ -923,7 +925,7 @@ private void addPrecisionErrors(ClassNode leftRedirect, ClassNode lhsType, Class
             }
         } else if (rightExpression instanceof ListExpression) {
             for (Expression element : ((ListExpression) rightExpression).getExpressions()) {
-                ClassNode rightComponentType = element.getType().redirect();
+                ClassNode rightComponentType = this.getType(element);
                 if (!checkCompatibleAssignmentTypes(leftComponentType, rightComponentType)
                         && !(isNullConstant(element) && !isPrimitiveType(leftComponentType))) {
                     addStaticTypeError("Cannot assign value of type " + rightComponentType.toString(false) + " into array of type " + lhsType.toString(false), rightExpression);

src/test/groovy/transform/stc/STCAssignmentTest.groovy

@@ -844,5 +844,33 @@ class STCAssignmentTest extends StaticTypeCheckingTestCase {
             assert fooParameterAssignment(null) == 42            
         '''
     }
+
+    void testIntegerArraySmartType() {
+        assertScript '''
+        def m() {
+            def a  = 1
+            Integer[] b = [a]
+        }            
+        '''
+    }
+
+    void testIntegerSecondDimArraySmartType() {
+        assertScript '''
+        def m() {
+            def a = new int[5]
+            int[][] b = [a]
+        }            
+        '''
+    }
+
+    void testMultiAssign() {
+        assertScript '''
+        def m() {
+            def row = ["", "", ""]
+            def (left, right) = [row[0], row[1]]
+            left.toUpperCase()
+        }            
+        '''
+    }
 }