Fix slice repr leaking the internal storage representation.

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

@@ -1,4 +1,4 @@
-# Copyright (c) 2018, 2025, Oracle and/or its affiliates.
+# Copyright (c) 2018, 2026, Oracle and/or its affiliates.
 # Copyright (c) 2013, Regents of the University of California
 #
 # All rights reserved.
@@ -196,6 +196,25 @@ def __index__(self):
         assert "slice indices must be integers" in str(e)
 
 
+def test_repr():
+    assert repr(slice(1, 2, 3)) == "slice(1, 2, 3)"
+    assert repr(slice(1, 2)) == "slice(1, 2, None)"
+    assert repr(slice(None)) == "slice(None, None, None)"
+    assert repr(slice(2**70)) == "slice(None, 1180591620717411303424, None)"
+    # each member is formatted with repr(), not with a debug representation
+    assert repr(slice(())) == "slice(None, (), None)"
+    assert repr(slice((1,))) == "slice(None, (1,), None)"
+    assert repr(slice([])) == "slice(None, [], None)"
+    assert repr(slice("")) == "slice(None, '', None)"
+    assert repr(slice(True, 2)) == "slice(True, 2, None)"
+
+    class Custom:
+        def __repr__(self):
+            return "<custom>"
+
+    assert repr(slice(Custom())) == "slice(None, <custom>, None)"
+
+
 def test_slice_eq():
     # Note: large numbers that do not get interned when boxed...
     assert slice(2, 10000, 10) == slice(2, 10000, 10)

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/slice/SliceBuiltins.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2025, Oracle and/or its affiliates.
+ * Copyright (c) 2017, 2026, Oracle and/or its affiliates.
  * Copyright (c) 2014, Regents of the University of California
  *
  * All rights reserved.
@@ -27,7 +27,6 @@
 
 import static com.oracle.graal.python.nodes.SpecialMethodNames.J___REDUCE__;
 import static com.oracle.graal.python.runtime.exception.PythonErrorType.ValueError;
-import static com.oracle.graal.python.util.PythonUtils.toTruffleStringUncached;
 
 import java.util.List;
 
@@ -46,11 +45,13 @@
 import com.oracle.graal.python.builtins.objects.slice.SliceNodes.ComputeIndices;
 import com.oracle.graal.python.builtins.objects.slice.SliceNodes.SliceCastToToBigInt;
 import com.oracle.graal.python.builtins.objects.slice.SliceNodes.SliceExactCastToInt;
+import com.oracle.graal.python.builtins.objects.str.StringUtils.SimpleTruffleStringFormatNode;
 import com.oracle.graal.python.builtins.objects.tuple.PTuple;
 import com.oracle.graal.python.builtins.objects.type.TpSlots;
 import com.oracle.graal.python.builtins.objects.type.slots.TpSlotHashFun.HashBuiltinNode;
 import com.oracle.graal.python.builtins.objects.type.slots.TpSlotRichCompare.RichCmpBuiltinNode;
 import com.oracle.graal.python.lib.PyObjectHashNode;
+import com.oracle.graal.python.lib.PyObjectReprAsTruffleStringNode;
 import com.oracle.graal.python.lib.PyObjectRichCompare;
 import com.oracle.graal.python.lib.PyObjectRichCompareBool;
 import com.oracle.graal.python.lib.PySliceNew;
@@ -65,7 +66,6 @@
 import com.oracle.graal.python.nodes.object.GetClassNode;
 import com.oracle.graal.python.runtime.exception.PException;
 import com.oracle.graal.python.runtime.object.PFactory;
-import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.dsl.Bind;
 import com.oracle.truffle.api.dsl.Cached;
 import com.oracle.truffle.api.dsl.Cached.Exclusive;
@@ -122,9 +122,14 @@ static Object threeArgs(@SuppressWarnings("unused") Object cls, Object start, Ob
     @GenerateNodeFactory
     abstract static class ReprNode extends PythonUnaryBuiltinNode {
         @Specialization
-        @TruffleBoundary
-        public static TruffleString repr(PSlice self) {
-            return toTruffleStringUncached(self.toString());
+        static TruffleString repr(VirtualFrame frame, PSlice self,
+                        @Bind Node inliningTarget,
+                        @Cached PyObjectReprAsTruffleStringNode reprNode,
+                        @Cached SimpleTruffleStringFormatNode simpleTruffleStringFormatNode) {
+            return simpleTruffleStringFormatNode.format("slice(%s, %s, %s)",
+                            reprNode.execute(frame, inliningTarget, self.getStart()),
+                            reprNode.execute(frame, inliningTarget, self.getStop()),
+                            reprNode.execute(frame, inliningTarget, self.getStep()));
         }
     }