[groovy] 01/05: GROOVY-10107: STC: check assign null before type parameter compatibility

[em...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

emilles pushed a commit to branch GROOVY_3_0_X
in repository https://gitbox.apache.org/repos/asf/groovy.git

commit bd5076773d3f81b22cd9ada6da266ca6847c881e
Author: Eric Milles <er...@thomsonreuters.com>
AuthorDate: Fri Jun 4 09:48:39 2021 -0500

    GROOVY-10107: STC: check assign null before type parameter compatibility
    
    Conflicts:
    	src/main/java/org/codehaus/groovy/transform/stc/StaticTypeCheckingSupport.java
---
 .../groovy/transform/stc/StaticTypeCheckingSupport.java    | 11 +++++------
 src/test/groovy/transform/stc/GenericsSTCTest.groovy       | 14 ++++++++++++++
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/src/main/java/org/codehaus/groovy/transform/stc/StaticTypeCheckingSupport.java b/src/main/java/org/codehaus/groovy/transform/stc/StaticTypeCheckingSupport.java
index 2a5fd0d..ddc4419 100644
--- a/src/main/java/org/codehaus/groovy/transform/stc/StaticTypeCheckingSupport.java
+++ b/src/main/java/org/codehaus/groovy/transform/stc/StaticTypeCheckingSupport.java
@@ -644,6 +644,10 @@ public abstract class StaticTypeCheckingSupport {
     }
 
     public static boolean checkCompatibleAssignmentTypes(final ClassNode left, final ClassNode right, final Expression rightExpression, final boolean allowConstructorCoercion) {
+        if (!isPrimitiveType(left) && isNullConstant(rightExpression)) {
+            return true;
+        }
+
         ClassNode leftRedirect = left.redirect();
         ClassNode rightRedirect = right.redirect();
         if (leftRedirect == rightRedirect) return true;
@@ -666,13 +670,8 @@ public abstract class StaticTypeCheckingSupport {
             }
         }
 
-        boolean rightExpressionIsNull = isNullConstant(rightExpression);
-        if (rightExpressionIsNull && !isPrimitiveType(left)) {
-            return true;
-        }
-
         // anything can be assigned to an Object, String, [Bb]oolean or Class receiver; except null to boolean
-        if (isWildcardLeftHandSide(leftRedirect) && !(boolean_TYPE.equals(left) && rightExpressionIsNull)) return true;
+        if (isWildcardLeftHandSide(leftRedirect) && !(boolean_TYPE.equals(left) && isNullConstant(rightExpression))) return true;
 
         if (leftRedirect == char_TYPE && rightRedirect == Character_TYPE) return true;
         if (leftRedirect == Character_TYPE && rightRedirect == char_TYPE) return true;
diff --git a/src/test/groovy/transform/stc/GenericsSTCTest.groovy b/src/test/groovy/transform/stc/GenericsSTCTest.groovy
index 6631867..0779304 100644
--- a/src/test/groovy/transform/stc/GenericsSTCTest.groovy
+++ b/src/test/groovy/transform/stc/GenericsSTCTest.groovy
@@ -1014,6 +1014,7 @@ class GenericsSTCTest extends StaticTypeCheckingTestCase {
         assertScript '''
             Map<String, Integer> foo = null
             Integer result = foo?.get('a')
+            assert result == null
         '''
     }
 
@@ -1021,6 +1022,7 @@ class GenericsSTCTest extends StaticTypeCheckingTestCase {
         assertScript '''
             List<Integer> foo = null
             Integer result = foo?.get(0)
+            assert result == null
         '''
     }
 
@@ -1029,8 +1031,20 @@ class GenericsSTCTest extends StaticTypeCheckingTestCase {
             List<Integer> foo = [1]
             foo = null
             Integer result = foo?.get(0)
+            assert result == null
         '''
+    }
 
+    // GROOVY-10107
+    void testAssignNullTypeParameterWithUpperBounds() {
+        assertScript '''
+            class C<T extends Number> {
+                void m() {
+                    T n = null
+                }
+            }
+            new C<Long>().m()
+        '''
     }
 
     void testMethodCallWithArgumentUsingNestedGenerics() {