fix(extension) Use mapping protocol on *MemoryView classes.

By replacing the `PySequenceProtocol` by `PyMappingProtocol`, the
`__setitem__` method finally compiles.

Author: Hywan

src/memory_view.rs

@@ -1,6 +1,6 @@
 //! The `Buffer` Python object to build WebAssembly values.
 
-use pyo3::{class::PySequenceProtocol, exceptions::IndexError, prelude::*};
+use pyo3::{class::PyMappingProtocol, exceptions::IndexError, prelude::*};
 use std::mem::size_of;
 use wasmer_runtime::memory::Memory;
 
@@ -21,7 +21,7 @@ macro_rules! memory_view {
         }
 
         #[pyproto]
-        impl PySequenceProtocol for $class_name {
+        impl PyMappingProtocol for $class_name {
             fn __len__(&self) -> PyResult<usize> {
                 Ok(self.memory.view::<$wasm_type>()[self.offset..].len() / size_of::<$wasm_type>())
             }
@@ -49,7 +49,6 @@ macro_rules! memory_view {
                 }
             }
 
-            /*
             fn __setitem__(&mut self, index: isize, value: u8) -> PyResult<()> {
                 let offset = self.offset;
                 let view = self.memory.view::<u8>();
@@ -74,7 +73,6 @@ macro_rules! memory_view {
                     Ok(())
                 }
             }
-            */
         }
     };
 }

tests/memory_view.py

@@ -33,13 +33,13 @@ def test_length(self):
             1114112
         )
 
-    #def test_get(self):
-    #    memory = Instance(TEST_BYTES).uint8_memory_view()
-    #    index = 7
-    #    value = 42
-    #    memory[index] = value
+    def test_get(self):
+        memory = Instance(TEST_BYTES).uint8_memory_view()
+        index = 7
+        value = 42
+        memory[index] = value
 
-    #    self.assertEqual(memory[index], value)
+        self.assertEqual(memory[index], value)
 
     def test_get_out_of_range(self):
         with self.assertRaises(IndexError) as context_manager:
@@ -52,16 +52,16 @@ def test_get_out_of_range(self):
             'Out of bound: Absolute index 1114113 is larger than the memory size 1114112.'
         )
 
-    #def test_set_out_of_range(self):
-    #    with self.assertRaises(IndexError) as context_manager:
-    #        memory = Instance(TEST_BYTES).uint8_memory_view()
-    #        memory[len(memory) + 1] = 42
+    def test_set_out_of_range(self):
+        with self.assertRaises(IndexError) as context_manager:
+            memory = Instance(TEST_BYTES).uint8_memory_view()
+            memory[len(memory) + 1] = 42
 
-    #    exception = context_manager.exception
-    #    self.assertEqual(
-    #        str(exception),
-    #        'Out of bound: Absolute index 1114113 is larger than the memory size 1114112.'
-    #    )
+        exception = context_manager.exception
+        self.assertEqual(
+            str(exception),
+            'Out of bound: Absolute index 1114113 is larger than the memory size 1114112.'
+        )
 
     def test_hello_world(self):
         instance = Instance(TEST_BYTES)
@@ -76,21 +76,21 @@ def test_hello_world(self):
 
         self.assertEqual(string, 'Hello, World!')
 
-    #def test_memory_views_share_the_same_buffer(self):
-    #    instance = Instance(TEST_BYTES)
-    #    int8 = instance.int8_memory_view()
-    #    int16 = instance.int16_memory_view()
-    #    int32 = instance.int32_memory_view()
-
-    #    int8[0] = 0b00000001
-    #    int8[1] = 0b00000100
-    #    int8[2] = 0b00010000
-    #    int8[3] = 0b01000000
-
-    #    self.assertEqual(int8[0], 0b00000001)
-    #    self.assertEqual(int8[1], 0b00000100)
-    #    self.assertEqual(int8[2], 0b00010000)
-    #    self.assertEqual(int8[3], 0b01000000)
-    #    self.assertEqual(int16[0], 0b00000100_00000001)
-    #    self.assertEqual(int16[1], 0b01000000_00010000)
-    #    self.assertEqual(int32[0], 0b01000000_00010000_00000100_00000001)
+    def test_memory_views_share_the_same_buffer(self):
+        instance = Instance(TEST_BYTES)
+        int8 = instance.int8_memory_view()
+        int16 = instance.int16_memory_view()
+        int32 = instance.int32_memory_view()
+
+        int8[0] = 0b00000001
+        int8[1] = 0b00000100
+        int8[2] = 0b00010000
+        int8[3] = 0b01000000
+
+        self.assertEqual(int8[0], 0b00000001)
+        self.assertEqual(int8[1], 0b00000100)
+        self.assertEqual(int8[2], 0b00010000)
+        self.assertEqual(int8[3], 0b01000000)
+        self.assertEqual(int16[0], 0b00000100_00000001)
+        self.assertEqual(int16[1], 0b01000000_00010000)
+        self.assertEqual(int32[0], 0b01000000_00010000_00000100_00000001)