Fix codegen of consuming setters/getters (#2172)

Make sure they reset their internal pointer to null after we call Rust
since it invalidates the Rust pointer after being called!

Closes #2168

Author: alexcrichton

crates/cli-support/src/js/mod.rs

@@ -2190,10 +2190,9 @@ impl<'a> Context<'a> {
                     AuxExportKind::Function(_) => {}
                     AuxExportKind::StaticFunction { .. } => {}
                     AuxExportKind::Constructor(class) => builder.constructor(class),
-                    AuxExportKind::Getter { .. } | AuxExportKind::Setter { .. } => {
-                        builder.method(false)
-                    }
-                    AuxExportKind::Method { consumed, .. } => builder.method(*consumed),
+                    AuxExportKind::Getter { consumed, .. }
+                    | AuxExportKind::Setter { consumed, .. }
+                    | AuxExportKind::Method { consumed, .. } => builder.method(*consumed),
                 }
             }
             Kind::Import(_) => {}
@@ -2257,7 +2256,7 @@ impl<'a> Context<'a> {
                         exported.has_constructor = true;
                         exported.push(&docs, "constructor", "", &code, ts_sig);
                     }
-                    AuxExportKind::Getter { class, field } => {
+                    AuxExportKind::Getter { class, field, .. } => {
                         let ret_ty = match export.generate_typescript {
                             true => match &ts_ret_ty {
                                 Some(s) => Some(s.as_str()),
@@ -2268,7 +2267,7 @@ impl<'a> Context<'a> {
                         let exported = require_class(&mut self.exported_classes, class);
                         exported.push_getter(&docs, field, &code, ret_ty);
                     }
-                    AuxExportKind::Setter { class, field } => {
+                    AuxExportKind::Setter { class, field, .. } => {
                         let arg_ty = match export.generate_typescript {
                             true => Some(ts_arg_tys[0].as_str()),
                             false => None,
@@ -3247,20 +3246,24 @@ fn check_duplicated_getter_and_setter_names(
                     AuxExportKind::Getter {
                         class: first_class,
                         field: first_field,
+                        consumed: _,
                     },
                     AuxExportKind::Getter {
                         class: second_class,
                         field: second_field,
+                        consumed: _,
                     },
                 ) => verify_exports(first_class, first_field, second_class, second_field)?,
                 (
                     AuxExportKind::Setter {
                         class: first_class,
                         field: first_field,
+                        consumed: _,
                     },
                     AuxExportKind::Setter {
                         class: second_class,
                         field: second_field,
+                        consumed: _,
                     },
                 ) => verify_exports(first_class, first_field, second_class, second_field)?,
                 _ => {}

crates/cli-support/src/wit/mod.rs

@@ -419,13 +419,15 @@ impl<'a> Context<'a> {
                             AuxExportKind::Getter {
                                 class,
                                 field: f.to_string(),
+                                consumed: export.consumed,
                             }
                         }
                         decode::OperationKind::Setter(f) => {
                             descriptor.arguments.insert(0, Descriptor::I32);
                             AuxExportKind::Setter {
                                 class,
                                 field: f.to_string(),
+                                consumed: export.consumed,
                             }
                         }
                         _ if op.is_static => AuxExportKind::StaticFunction {
@@ -806,6 +808,7 @@ impl<'a> Context<'a> {
                     kind: AuxExportKind::Getter {
                         class: struct_.name.to_string(),
                         field: field.name.to_string(),
+                        consumed: false,
                     },
                     generate_typescript: field.generate_typescript,
                 },
@@ -832,6 +835,7 @@ impl<'a> Context<'a> {
                     kind: AuxExportKind::Setter {
                         class: struct_.name.to_string(),
                         field: field.name.to_string(),
+                        consumed: false,
                     },
                     generate_typescript: field.generate_typescript,
                 },

crates/cli-support/src/wit/nonstandard.rs

@@ -105,12 +105,22 @@ pub enum AuxExportKind {
     /// This function is intended to be a getter for a field on a class. The
     /// first argument is the internal pointer and the returned value is
     /// expected to be the field.
-    Getter { class: String, field: String },
+    Getter {
+        class: String,
+        field: String,
+        // same as `consumed` in `Method`
+        consumed: bool,
+    },
 
     /// This function is intended to be a setter for a field on a class. The
     /// first argument is the internal pointer and the second argument is
     /// expected to be the field's new value.
-    Setter { class: String, field: String },
+    Setter {
+        class: String,
+        field: String,
+        // same as `consumed` in `Method`
+        consumed: bool,
+    },
 
     /// This is a free function (ish) but scoped inside of a class name.
     StaticFunction { class: String, name: String },

crates/cli-support/src/wit/section.rs

@@ -369,15 +369,15 @@ fn check_standard_export(export: &AuxExport) -> Result<(), Error> {
                 name,
             );
         }
-        AuxExportKind::Getter { class, field } => {
+        AuxExportKind::Getter { class, field, .. } => {
             bail!(
                 "cannot export `{}::{}` getter function when generating \
                  a standalone WebAssembly module with no JS glue",
                 class,
                 field,
             );
         }
-        AuxExportKind::Setter { class, field } => {
+        AuxExportKind::Setter { class, field, .. } => {
             bail!(
                 "cannot export `{}::{}` setter function when generating \
                  a standalone WebAssembly module with no JS glue",

examples/add/src/lib.rs

@@ -4,3 +4,21 @@ use wasm_bindgen::prelude::*;
 pub fn add(a: u32, b: u32) -> u32 {
     a + b
 }
+
+#[wasm_bindgen]
+#[derive(Copy, Clone)]
+pub struct Answer(u32);
+
+#[wasm_bindgen]
+impl Answer {
+    pub fn new() -> Answer {
+        Answer(41)
+    }
+    #[wasm_bindgen(getter)]
+    pub fn the_answer(self) -> u32 {
+        self.0 + 1
+    }
+    pub fn foo(self) -> u32 {
+        self.0 + 1
+    }
+}

tests/wasm/validate_prt.js

@@ -33,4 +33,11 @@ exports.js_works = () => {
     useMoved();
     moveMoved();
     methodMoved();
+
+    const a = new wasm.Fruit('a');
+    a.prop;
+    assertMovedPtrThrows(() => a.prop);
+    const b = new wasm.Fruit('a');
+    b.prop = 3;
+    assertMovedPtrThrows(() => { b.prop = 4; });
 };

tests/wasm/validate_prt.rs

@@ -25,6 +25,14 @@ impl Fruit {
     pub fn rot(self) {
         drop(self);
     }
+
+    #[wasm_bindgen(getter)]
+    pub fn prop(self) -> u32 {
+        0
+    }
+
+    #[wasm_bindgen(setter)]
+    pub fn set_prop(self, _val: u32) {}
 }
 
 #[wasm_bindgen]