Iterator

Author: youknowone

Lib/test/test_io.py

@@ -4276,10 +4276,6 @@ def test_reconfigure_write_through(self):
     def test_repr(self):
         return super().test_repr()
 
-    @unittest.expectedFailure # TODO: RUSTPYTHON
-    def test_telling(self):
-        return super().test_telling()
-
     @unittest.expectedFailure # TODO: RUSTPYTHON
     def test_uninitialized(self):
         return super().test_uninitialized()

crates/vm/src/stdlib/io.rs

@@ -2473,7 +2473,7 @@ mod _io {
         vm.call_method(&textio.buffer, "flush", ())
     }
 
-    #[pyclass(with(Constructor, Initializer, Destructor), flags(BASETYPE))]
+    #[pyclass(with(Constructor, Initializer, Destructor, Iterable, IterNext), flags(BASETYPE))]
     impl TextIOWrapper {
         #[pymethod]
         fn reconfigure(&self, args: TextIOWrapperArgs, vm: &VirtualMachine) -> PyResult<()> {
@@ -3348,6 +3348,44 @@ mod _io {
         }
     }
 
+    impl Iterable for TextIOWrapper {
+        fn slot_iter(zelf: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+            check_closed(&zelf, vm)?;
+            Ok(zelf)
+        }
+
+        fn iter(_zelf: PyRef<Self>, _vm: &VirtualMachine) -> PyResult {
+            unreachable!("slot_iter is implemented")
+        }
+    }
+
+    impl IterNext for TextIOWrapper {
+        fn slot_iternext(zelf: &PyObject, vm: &VirtualMachine) -> PyResult<PyIterReturn> {
+            // Set telling = false during iteration (matches CPython behavior)
+            let textio_ref: PyRef<TextIOWrapper> = zelf.downcast_ref::<TextIOWrapper>().unwrap().to_owned();
+            {
+                let mut textio = textio_ref.lock(vm)?;
+                textio.telling = false;
+            }
+
+            let line = vm.call_method(zelf, "readline", ())?;
+
+            if !line.clone().try_to_bool(vm)? {
+                // Restore telling on StopIteration
+                let mut textio = textio_ref.lock(vm)?;
+                textio.snapshot = None;
+                textio.telling = textio.seekable;
+                Ok(PyIterReturn::StopIteration(None))
+            } else {
+                Ok(PyIterReturn::Return(line))
+            }
+        }
+
+        fn next(_zelf: &Py<Self>, _vm: &VirtualMachine) -> PyResult<PyIterReturn> {
+            unreachable!("slot_iternext is implemented")
+        }
+    }
+
     #[pyattr]
     #[pyclass(name)]
     #[derive(Debug, PyPayload, Default)]