Convert iterator

RustPython · windelbouwman · Mar 10, 2019 · Mar 9, 2019 · Mar 9, 2019 · Mar 9, 2019
commit 157d18d7a155dfaa740426a68f43b0face68c203
diff --git a/vm/src/obj/objbytes.rs b/vm/src/obj/objbytes.rs
@@ -5,8 +5,8 @@ use std::ops::Deref;
 use super::objint;
 use super::objtype;
 use crate::pyobject::{
-    PyContext, PyFuncArgs, PyObject, PyObjectPayload, PyObjectPayload2, PyObjectRef, PyResult,
-    TypeProtocol,
+    PyContext, PyFuncArgs, PyIteratorValue, PyObject, PyObjectPayload, PyObjectPayload2,
+    PyObjectRef, PyResult, TypeProtocol,
 };
 use crate::vm::VirtualMachine;
 use num_traits::ToPrimitive;
@@ -209,9 +209,11 @@ fn bytes_iter(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(vm, args, required = [(obj, Some(vm.ctx.bytes_type()))]);
 
     let iter_obj = PyObject::new(
-        PyObjectPayload::Iterator {
-            position: Cell::new(0),
-            iterated_obj: obj.clone(),
+        PyObjectPayload::AnyRustValue {
+            value: Box::new(PyIteratorValue {
+                position: Cell::new(0),
+                iterated_obj: obj.clone(),
+            }),
         },
         vm.ctx.iter_type(),
     );

diff --git a/vm/src/obj/objdict.rs b/vm/src/obj/objdict.rs
@@ -6,8 +6,8 @@ use super::objiter;
 use super::objstr;
 use super::objtype;
 use crate::pyobject::{
-    PyAttributes, PyContext, PyFuncArgs, PyObject, PyObjectPayload, PyObjectPayload2, PyObjectRef,
-    PyResult, TypeProtocol,
+    PyAttributes, PyContext, PyFuncArgs, PyIteratorValue, PyObject, PyObjectPayload,
+    PyObjectPayload2, PyObjectRef, PyResult, TypeProtocol,
 };
 use crate::vm::{ReprGuard, VirtualMachine};
 
@@ -249,9 +249,11 @@ fn dict_iter(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     let key_list = vm.ctx.new_list(keys);
 
     let iter_obj = PyObject::new(
-        PyObjectPayload::Iterator {
-            position: Cell::new(0),
-            iterated_obj: key_list,
+        PyObjectPayload::AnyRustValue {
+            value: Box::new(PyIteratorValue {
+                position: Cell::new(0),
+                iterated_obj: key_list,
+            }),
         },
         vm.ctx.iter_type(),
     );
@@ -269,9 +271,11 @@ fn dict_values(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     let values_list = vm.ctx.new_list(values);
 
     let iter_obj = PyObject::new(
-        PyObjectPayload::Iterator {
-            position: Cell::new(0),
-            iterated_obj: values_list,
+        PyObjectPayload::AnyRustValue {
+            value: Box::new(PyIteratorValue {
+                position: Cell::new(0),
+                iterated_obj: values_list,
+            }),
         },
         vm.ctx.iter_type(),
     );
@@ -289,9 +293,11 @@ fn dict_items(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     let items_list = vm.ctx.new_list(items);
 
     let iter_obj = PyObject::new(
-        PyObjectPayload::Iterator {
-            position: Cell::new(0),
-            iterated_obj: items_list,
+        PyObjectPayload::AnyRustValue {
+            value: Box::new(PyIteratorValue {
+                position: Cell::new(0),
+                iterated_obj: items_list,
+            }),
         },
         vm.ctx.iter_type(),
     );

diff --git a/vm/src/obj/objiter.rs b/vm/src/obj/objiter.rs
@@ -3,7 +3,7 @@
  */
 
 use crate::pyobject::{
-    PyContext, PyFuncArgs, PyObjectPayload, PyObjectRef, PyResult, TypeProtocol,
+    PyContext, PyFuncArgs, PyIteratorValue, PyObjectRef, PyResult, TypeProtocol,
 };
 use crate::vm::VirtualMachine;
 
@@ -128,10 +128,10 @@ fn iter_new(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
 fn iter_next(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(vm, args, required = [(iter, Some(vm.ctx.iter_type()))]);
 
-    if let PyObjectPayload::Iterator {
+    if let Some(PyIteratorValue {
         ref position,
         iterated_obj: ref iterated_obj_ref,
-    } = iter.payload
+    }) = iter.payload()
     {
         if let Some(range) = iterated_obj_ref.payload::<PyRange>() {
             if let Some(int) = range.get(position.get()) {

diff --git a/vm/src/obj/objlist.rs b/vm/src/obj/objlist.rs
@@ -10,8 +10,8 @@ use super::objstr;
 use super::objtype;
 use crate::function::PyRef;
 use crate::pyobject::{
-    IdProtocol, OptionalArg, PyContext, PyFuncArgs, PyObject, PyObjectPayload, PyObjectPayload2,
-    PyObjectRef, PyResult, TypeProtocol,
+    IdProtocol, OptionalArg, PyContext, PyFuncArgs, PyIteratorValue, PyObject, PyObjectPayload,
+    PyObjectPayload2, PyObjectRef, PyResult, TypeProtocol,
 };
 use crate::vm::{ReprGuard, VirtualMachine};
 use num_traits::ToPrimitive;
@@ -112,9 +112,11 @@ impl PyListRef {
 
     fn iter(self, vm: &mut VirtualMachine) -> PyObjectRef {
         PyObject::new(
-            PyObjectPayload::Iterator {
-                position: Cell::new(0),
-                iterated_obj: self.into_object(),
+            PyObjectPayload::AnyRustValue {
+                value: Box::new(PyIteratorValue {
+                    position: Cell::new(0),
+                    iterated_obj: self.into_object(),
+                }),
             },
             vm.ctx.iter_type(),
         )

diff --git a/vm/src/obj/objrange.rs b/vm/src/obj/objrange.rs
@@ -6,8 +6,8 @@ use num_integer::Integer;
 use num_traits::{One, Signed, ToPrimitive, Zero};
 
 use crate::pyobject::{
-    PyContext, PyFuncArgs, PyObject, PyObjectPayload, PyObjectPayload2, PyObjectRef, PyResult,
-    TypeProtocol,
+    PyContext, PyFuncArgs, PyIteratorValue, PyObject, PyObjectPayload, PyObjectPayload2,
+    PyObjectRef, PyResult, TypeProtocol,
 };
 use crate::vm::VirtualMachine;
 
@@ -240,9 +240,11 @@ fn range_iter(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(vm, args, required = [(range, Some(vm.ctx.range_type()))]);
 
     Ok(PyObject::new(
-        PyObjectPayload::Iterator {
-            position: Cell::new(0),
-            iterated_obj: range.clone(),
+        PyObjectPayload::AnyRustValue {
+            value: Box::new(PyIteratorValue {
+                position: Cell::new(0),
+                iterated_obj: range.clone(),
+            }),
         },
         vm.ctx.iter_type(),
     ))
@@ -254,14 +256,16 @@ fn range_reversed(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     let range = get_value(zelf).reversed();
 
     Ok(PyObject::new(
-        PyObjectPayload::Iterator {
-            position: Cell::new(0),
-            iterated_obj: PyObject::new(
-                PyObjectPayload::AnyRustValue {
-                    value: Box::new(range),
-                },
-                vm.ctx.range_type(),
-            ),
+        PyObjectPayload::AnyRustValue {
+            value: Box::new(PyIteratorValue {
+                position: Cell::new(0),
+                iterated_obj: PyObject::new(
+                    PyObjectPayload::AnyRustValue {
+                        value: Box::new(range),
+                    },
+                    vm.ctx.range_type(),
+                ),
+            }),
         },
         vm.ctx.iter_type(),
     ))

diff --git a/vm/src/obj/objset.rs b/vm/src/obj/objset.rs
@@ -13,8 +13,8 @@ use super::objiter;
 use super::objstr;
 use super::objtype;
 use crate::pyobject::{
-    PyContext, PyFuncArgs, PyObject, PyObjectPayload, PyObjectPayload2, PyObjectRef, PyResult,
-    TypeProtocol,
+    PyContext, PyFuncArgs, PyIteratorValue, PyObject, PyObjectPayload, PyObjectPayload2,
+    PyObjectRef, PyResult, TypeProtocol,
 };
 use crate::vm::{ReprGuard, VirtualMachine};
 
@@ -566,9 +566,11 @@ fn set_iter(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     let items = get_elements(zelf).values().cloned().collect();
     let set_list = vm.ctx.new_list(items);
     let iter_obj = PyObject::new(
-        PyObjectPayload::Iterator {
-            position: Cell::new(0),
-            iterated_obj: set_list,
+        PyObjectPayload::AnyRustValue {
+            value: Box::new(PyIteratorValue {
+                position: Cell::new(0),
+                iterated_obj: set_list,
+            }),
         },
         vm.ctx.iter_type(),
     );

diff --git a/vm/src/obj/objtuple.rs b/vm/src/obj/objtuple.rs
@@ -3,8 +3,8 @@ use std::hash::{Hash, Hasher};
 
 use crate::function::PyRef;
 use crate::pyobject::{
-    IdProtocol, OptionalArg, PyContext, PyObject, PyObjectPayload, PyObjectPayload2, PyObjectRef,
-    PyResult,
+    IdProtocol, OptionalArg, PyContext, PyIteratorValue, PyObject, PyObjectPayload,
+    PyObjectPayload2, PyObjectRef, PyResult,
 };
 use crate::vm::{ReprGuard, VirtualMachine};
 
@@ -127,9 +127,11 @@ impl PyTupleRef {
 
     fn iter(self, vm: &mut VirtualMachine) -> PyObjectRef {
         PyObject::new(
-            PyObjectPayload::Iterator {
-                position: Cell::new(0),
-                iterated_obj: self.into_object(),
+            PyObjectPayload::AnyRustValue {
+                value: Box::new(PyIteratorValue {
+                    position: Cell::new(0),
+                    iterated_obj: self.into_object(),
+                }),
             },
             vm.ctx.iter_type(),
         )

diff --git a/vm/src/pyobject.rs b/vm/src/pyobject.rs
@@ -100,17 +100,6 @@ impl fmt::Display for PyObject {
     }
 }
 
-/*
- // Idea: implement the iterator trait upon PyObjectRef
-impl Iterator for (VirtualMachine, PyObjectRef) {
-    type Item = char;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        // call method ("_next__")
-    }
-}
-*/
-
 #[derive(Debug)]
 pub struct PyContext {
     pub bytes_type: PyObjectRef,
@@ -1496,10 +1485,6 @@ into_py_native_func_tuple!((a, A), (b, B), (c, C), (d, D), (e, E));
 /// of rust data for a particular python object. Determine the python type
 /// by using for example the `.typ()` method on a python object.
 pub enum PyObjectPayload {
-    Iterator {
-        position: Cell<usize>,
-        iterated_obj: PyObjectRef,
-    },
     Slice {
         start: Option<BigInt>,
         stop: Option<BigInt>,
@@ -1524,12 +1509,25 @@ impl Default for PyObjectPayload {
     }
 }
 
+// TODO: This is a workaround and shouldn't exist.
+//       Each iterable type should have its own distinct iterator type.
+#[derive(Debug)]
+pub struct PyIteratorValue {
+    pub position: Cell<usize>,
+    pub iterated_obj: PyObjectRef,
+}
+
+impl PyObjectPayload2 for PyIteratorValue {
+    fn required_type(ctx: &PyContext) -> PyObjectRef {
+        ctx.iter_type()
+    }
+}
+
 impl fmt::Debug for PyObjectPayload {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match self {
             PyObjectPayload::MemoryView { ref obj } => write!(f, "bytes/bytearray {:?}", obj),
             PyObjectPayload::WeakRef { .. } => write!(f, "weakref"),
-            PyObjectPayload::Iterator { .. } => write!(f, "iterator"),
             PyObjectPayload::Slice { .. } => write!(f, "slice"),
             PyObjectPayload::AnyRustValue { value } => value.fmt(f),
         }