[Mlir-commits] [mlir] [MLIR][Python] make Sliceable inherit from Sequence (PR #170551)

[Maksim Levental]

https://github.com/makslevental updated https://github.com/llvm/llvm-project/pull/170551

>From 7b233f77d7a0786aec27db1a65cecd85ee1e9955 Mon Sep 17 00:00:00 2001
From: makslevental <maksim.levental at gmail.com>
Date: Wed, 3 Dec 2025 12:22:06 -0800
Subject: [PATCH] [MLIR][Python] make Sliceable inherit from Sequence

---
 mlir/lib/Bindings/Python/NanobindUtils.h | 12 +++++++++++-
 mlir/test/python/ir/operation.py         |  4 ++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/mlir/lib/Bindings/Python/NanobindUtils.h b/mlir/lib/Bindings/Python/NanobindUtils.h
index 658e8ad5330ef..aea195fecae82 100644
--- a/mlir/lib/Bindings/Python/NanobindUtils.h
+++ b/mlir/lib/Bindings/Python/NanobindUtils.h
@@ -19,6 +19,7 @@
 #include "llvm/Support/raw_ostream.h"
 
 #include <string>
+#include <typeinfo>
 #include <variant>
 
 template <>
@@ -344,7 +345,16 @@ class Sliceable {
 
   /// Binds the indexing and length methods in the Python class.
   static void bind(nanobind::module_ &m) {
-    auto clazz = nanobind::class_<Derived>(m, Derived::pyClassName)
+    const std::type_info &elemTy = typeid(ElementTy);
+    PyObject *elemTyInfo = nanobind::detail::nb_type_lookup(&elemTy);
+    assert(elemTyInfo &&
+           "expected nb_type_lookup to succeed for Sliceable elemTy");
+    nanobind::handle elemTyName = nanobind::detail::nb_type_name(elemTyInfo);
+    std::string sig = std::string("class ") + Derived::pyClassName +
+                      "(collections.abc.Sequence[" +
+                      nanobind::cast<std::string>(elemTyName) + "])";
+    auto clazz = nanobind::class_<Derived>(m, Derived::pyClassName,
+                                           nanobind::sig(sig.c_str()))
                      .def("__add__", &Sliceable::dunderAdd);
     Derived::bindDerived(clazz);
 
diff --git a/mlir/test/python/ir/operation.py b/mlir/test/python/ir/operation.py
index ca99c2a985242..d124c284197b8 100644
--- a/mlir/test/python/ir/operation.py
+++ b/mlir/test/python/ir/operation.py
@@ -43,6 +43,10 @@ def testTraverseOpRegionBlockIterators():
     )
     op = module.operation
     assert op.context is ctx
+    # Note, __nb_signature__ stores the fully-qualified signature - the actual type stub emitted is
+    # class RegionSequence(Sequence[Region])
+    # CHECK: class RegionSequence(collections.abc.Sequence[mlir._mlir_libs._mlir.ir.Region])
+    print(RegionSequence.__nb_signature__)
     # Get the block using iterators off of the named collections.
     regions = list(op.regions[:])
     blocks = list(regions[0].blocks)