GROOVY-11375, GROOVY-11769: SC: lookup type of variable before target

see also GROOVY-9344, GROOVY-9607

4_0_X backport

Author: eric-milles

src/main/java/org/codehaus/groovy/classgen/asm/sc/StaticTypesTypeChooser.java

@@ -32,20 +32,23 @@
  * type information from node metadata generated by the static type checker.
  */
 public class StaticTypesTypeChooser extends StatementMetaTypeChooser {
+
     @Override
     public ClassNode resolveType(final Expression exp, final ClassNode current) {
-        ASTNode target = getTarget(exp); // see GROOVY-9344, GROOVY-9607
-
-        ClassNode inferredType = target.getNodeMetaData(StaticTypesMarker.DECLARATION_INFERRED_TYPE);
+        ClassNode inferredType = exp.getNodeMetaData(StaticTypesMarker.DECLARATION_INFERRED_TYPE);
+        if (inferredType == null) {
+            inferredType = exp.getNodeMetaData(StaticTypesMarker.INFERRED_TYPE);
+        }
         if (inferredType == null) {
-            inferredType = target.getNodeMetaData(StaticTypesMarker.INFERRED_TYPE);
+            ASTNode node = getTarget(exp); // GROOVY-9344, GROOVY-9607
+            inferredType = node.getNodeMetaData(StaticTypesMarker.INFERRED_TYPE);
         }
         if (inferredType != null && !isPrimitiveVoid(inferredType)) {
             return inferredType;
         }
 
-        // AsmClassGenerator may create "this" expressions that the type checker knows nothing about
-        if (target instanceof VariableExpression && ((VariableExpression) target).isThisExpression()) {
+        // AsmClassGenerator creates "this" expressions that the type checker knows nothing about
+        if (exp instanceof VariableExpression && ((VariableExpression) exp).isThisExpression()) {
             return current;
         }
 

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

@@ -645,6 +645,21 @@ class STCAssignmentTest extends StaticTypeCheckingTestCase {
         '''
     }
 
+    void testCastObjectToInterface() {
+        assertScript '''
+            List<Object> m(object) {
+                if (object == null) return new ArrayList<>()
+                if (object instanceof Collection) return new ArrayList<Object>((Collection) object)
+                return [object]
+            }
+            def item = 0
+            def list = [1,2]
+            assert m(null).size() == 0
+            assert m(item).size() == 1
+            assert m(list).size() == 2
+        '''
+    }
+
     void testIfElseBranch() {
         shouldFailWithMessages '''
             def x

src/test/groovy/groovy/transform/stc/STCnAryExpressionTest.groovy

@@ -132,6 +132,26 @@ class STCnAryExpressionTest extends StaticTypeCheckingTestCase {
         '''
     }
 
+    // GROOVY-11375
+    void testShiftOnPrimitivesVariableFlowType() {
+        assertScript '''
+            def x = "--"
+            x = x.size()
+            def y = x << x
+            assert y === 8
+        '''
+    }
+
+    // GROOVY-11375
+    void testPowerOnPrimitivesVariableFlowType() {
+        assertScript '''
+            def x = "--"
+            x = x.size()
+            def y = x ** x
+            assert y === 4
+        '''
+    }
+
     // GROOVY-5644
     void testSpaceshipOperatorNoAmbiguousError() {
         assertScript '''

src/test/groovy/org/codehaus/groovy/classgen/asm/sc/AssignmentsStaticCompileTest.groovy

@@ -31,4 +31,12 @@ final class AssignmentsStaticCompileTest extends STCAssignmentTest implements St
         String bytecode = astTrees['C'][1]
         assert !bytecode.contains('ScriptBytecodeAdapter.setGroovyObjectProperty') : '"c.i += 10" should use setter, not dynamic property'
     }
+
+    @Override // GROOVY-11769
+    void testCastObjectToInterface() {
+        super.testCastObjectToInterface()
+        String bytecode = astTrees.values()[0][1]
+        bytecode = bytecode.substring(bytecode.indexOf('m(Ljava/lang/Object;)'))
+        assert bytecode.count('CHECKCAST') == 1 // guarded typecast isn't groovy
+    }
 }