[GR-50783] CallTernaryMethodNode should reverse the arguments for reverse builtins.

PullRequest: graalpython/3098

Author: steve-s

graalpython/com.oracle.graal.python.test/src/tests/test_binary_arithmetic.py

@@ -326,6 +326,26 @@ def __pow__(self, power):
         from pow_tests import test_pow
         test_pow()
 
+    # Needs to run multiple times to invoke the cached node too
+    def call_rpow(x):
+        return x.__rpow__(2, 10)
+
+    assert call_rpow(3) == 8
+    assert call_rpow(3) == 8
+
+    class MyRPow:
+        def __pow__(self, other, modulus=None):
+            return (2 ** other) % modulus if modulus else 2 ** other
+        def __rpow__(self, other, modulus=None):
+            return (3 ** other) % modulus if modulus else 3 ** other
+
+    assert MyRPow() ** 2 == 4
+    assert pow(MyRPow(), 2, 3) == 1
+
+    assert 2 ** MyRPow() == 9
+    # This works on GraalPy, but not on CPython: feature or a bug?
+    # assert_exception(lambda: pow(2, MyRPow(), 5), TypeError)
+
 def test_slot1binfull():
     class A:
         def __add__(self, other):

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/method/PDecoratedMethod.java

@@ -52,7 +52,7 @@
 /**
  * Storage for classmethods, staticmethods and instancemethods
  */
-public class PDecoratedMethod extends PythonBuiltinObject implements BoundBuiltinCallable<Object> {
+public final class PDecoratedMethod extends PythonBuiltinObject implements BoundBuiltinCallable<Object> {
     private Object callable;
 
     public PDecoratedMethod(Object cls, Shape instanceShape) {

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/call/special/CallTernaryMethodNode.java

@@ -111,7 +111,7 @@ static Object doBuiltinFunctionCachedReverse(VirtualFrame frame, @SuppressWarnin
                     @SuppressWarnings("unused") @Cached("func") PBuiltinFunction cachedFunc,
                     @SuppressWarnings("unused") @Cached("isForReverseBinaryOperation(func.getCallTarget())") boolean isReverse,
                     @Cached("getBuiltin(frame, func, 3)") PythonBuiltinBaseNode builtinNode) {
-        return callTernaryBuiltin(frame, builtinNode, arg1, arg2, arg3);
+        return callTernaryBuiltin(frame, builtinNode, arg2, arg1, arg3);
     }
 
     @Specialization(guards = {"func.getCallTarget() == ct", "builtinNode != null", "!isReverse"}, //
@@ -129,7 +129,7 @@ static Object doBuiltinFunctionCtCachedReverse(VirtualFrame frame, @SuppressWarn
                     @SuppressWarnings("unused") @Cached("func.getCallTarget()") RootCallTarget ct,
                     @SuppressWarnings("unused") @Cached("isForReverseBinaryOperation(func.getCallTarget())") boolean isReverse,
                     @Cached("getBuiltin(frame, func, 3)") PythonBuiltinBaseNode builtinNode) {
-        return callTernaryBuiltin(frame, builtinNode, arg1, arg2, arg3);
+        return callTernaryBuiltin(frame, builtinNode, arg2, arg1, arg3);
     }
 
     @Specialization(guards = {"isSingleContext()", "func == cachedFunc", "builtinNode != null", "!takesSelfArg"}, limit = "getCallSiteInlineCacheMaxDepth()")