Merge pull request #3165 from wasmerio/make-wasmer-js-work-on-core

Initial port of make test-js-core (port wasmer API to core)

.github/workflows/test-js.yaml

@@ -46,3 +46,6 @@ jobs:
 
       - name: Compile Wasmer to WebAssembly and test with a JavaScript host
         run: make test-js
+
+      - name: Compile Wasmer to WebAssembly and test with a JavaScript host (no-std)
+        run: make test-js-core

Makefile

@@ -486,6 +486,9 @@ test-packages:
 
 test-js: test-js-api test-js-wasi
 
+test-js-core:
+	cd lib/api && wasm-pack test --node -- --no-default-features --features js,core,wasm-types-polyfill,wat
+
 test-js-api:
 	cd lib/api && wasm-pack test --node -- --no-default-features --features js-default,wat
 

lib/api/src/js/error.rs

@@ -1,3 +1,5 @@
+#[cfg(feature = "core")]
+use crate::alloc::borrow::Cow;
 use crate::js::lib::std::string::String;
 use crate::js::trap::RuntimeError;
 #[cfg(feature = "std")]
@@ -116,7 +118,7 @@ impl From<wasm_bindgen::JsValue> for WasmError {
 pub enum SerializeError {
     /// An IO error
     #[cfg_attr(feature = "std", error(transparent))]
-    Io(#[from] std::io::Error),
+    Io(#[cfg_attr(feature = "std", from)] std::io::Error),
     /// A generic serialization error
     #[cfg_attr(feature = "std", error("{0}"))]
     Generic(String),
@@ -125,11 +127,12 @@ pub enum SerializeError {
 /// The Deserialize error can occur when loading a
 /// compiled Module from a binary.
 /// Copied from wasmer_compiler::DeSerializeError
-#[derive(Error, Debug)]
+#[derive(Debug)]
+#[cfg_attr(feature = "std", derive(Error))]
 pub enum DeserializeError {
     /// An IO error
     #[cfg_attr(feature = "std", error(transparent))]
-    Io(#[from] std::io::Error),
+    Io(#[cfg_attr(feature = "std", from)] std::io::Error),
     /// A generic deserialization error
     #[cfg_attr(feature = "std", error("{0}"))]
     Generic(String),
@@ -151,19 +154,20 @@ pub enum DeserializeError {
 /// This is based on the [link error][link-error] API.
 ///
 /// [link-error]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WebAssembly/LinkError
-#[derive(Error, Debug)]
-#[error("Link error: {0}")]
+#[derive(Debug)]
+#[cfg_attr(feature = "std", derive(Error))]
+#[cfg_attr(feature = "std", error("Link error: {0}"))]
 pub enum LinkError {
     /// An error occurred when checking the import types.
-    #[error("Error while importing {0:?}.{1:?}: {2}")]
+    #[cfg_attr(feature = "std", error("Error while importing {0:?}.{1:?}: {2}"))]
     Import(String, String, ImportError),
 
     #[cfg(not(target_arch = "wasm32"))]
     /// A trap ocurred during linking.
-    #[error("RuntimeError occurred during linking: {0}")]
+    #[cfg_attr(feature = "std", error("RuntimeError occurred during linking: {0}"))]
     Trap(#[source] RuntimeError),
     /// Insufficient resources available for linking.
-    #[error("Insufficient resources: {0}")]
+    #[cfg_attr(feature = "std", error("Insufficient resources: {0}"))]
     Resource(String),
 }
 

lib/api/src/js/externals/function.rs

@@ -1148,6 +1148,10 @@ mod inner {
                         match result {
                             Ok(Ok(result)) => return result.into_c_struct(&mut store),
                             #[allow(deprecated)]
+                            #[cfg(feature = "std")]
+                            Ok(Err(trap)) => RuntimeError::raise(Box::new(trap)),
+                            #[cfg(feature = "core")]
+                            #[allow(deprecated)]
                             Ok(Err(trap)) => RuntimeError::raise(Box::new(trap)),
                             Err(_panic) => unimplemented!(),
                         }
@@ -1191,6 +1195,10 @@ mod inner {
 
                         match result {
                             Ok(Ok(result)) => return result.into_c_struct(&mut store),
+                            #[cfg(feature = "std")]
+                            #[allow(deprecated)]
+                            Ok(Err(trap)) => RuntimeError::raise(Box::new(trap)),
+                            #[cfg(feature = "core")]
                             #[allow(deprecated)]
                             Ok(Err(trap)) => RuntimeError::raise(Box::new(trap)),
                             Err(_panic) => unimplemented!(),

lib/api/src/js/mod.rs

@@ -7,12 +7,12 @@ compile_error!(
 compile_error!("Both the `std` and `core` features are disabled. Please enable one of them.");
 
 #[cfg(feature = "core")]
-extern crate alloc;
+pub(crate) extern crate alloc;
 
 mod lib {
     #[cfg(feature = "core")]
     pub mod std {
-        pub use alloc::{borrow, boxed, str, string, sync, vec};
+        pub use crate::alloc::{borrow, boxed, str, string, sync, vec};
         pub use core::fmt;
         pub use hashbrown as collections;
     }
@@ -23,7 +23,7 @@ mod lib {
     }
 }
 
-mod error;
+pub(crate) mod error;
 mod export;
 mod exports;
 mod externals;

lib/api/src/js/trap.rs

@@ -6,6 +6,89 @@ use wasm_bindgen::convert::FromWasmAbi;
 use wasm_bindgen::prelude::*;
 use wasm_bindgen::JsValue;
 
+pub trait CoreError: fmt::Debug + fmt::Display {
+    fn source(&self) -> Option<&(dyn CoreError + 'static)> {
+        None
+    }
+
+    fn type_id(&self) -> core::any::TypeId
+    where
+        Self: 'static,
+    {
+        core::any::TypeId::of::<Self>()
+    }
+
+    fn description(&self) -> &str {
+        "description() is deprecated; use Display"
+    }
+    fn cause(&self) -> Option<&dyn CoreError> {
+        self.source()
+    }
+}
+
+impl<T: fmt::Debug + fmt::Display> CoreError for T {}
+
+impl dyn CoreError + 'static {
+    /// Returns `true` if the inner type is the same as `T`.
+    pub fn core_is_equal<T: CoreError + 'static>(&self) -> bool {
+        let t = core::any::TypeId::of::<T>();
+        let concrete = self.type_id();
+        t == concrete
+    }
+}
+
+impl dyn CoreError + Send + Sync + 'static {
+    /// Returns `true` if the inner type is the same as `T`.
+    pub fn core_is_equal<T: CoreError + 'static>(&self) -> bool {
+        let t = core::any::TypeId::of::<T>();
+        let concrete = self.type_id();
+        t == concrete
+    }
+}
+
+impl dyn CoreError + Send {
+    #[inline]
+    /// Attempts to downcast the box to a concrete type.
+    pub fn downcast_core<T: CoreError + 'static>(
+        self: Box<Self>,
+    ) -> Result<Box<T>, Box<dyn CoreError + Send>> {
+        let err: Box<dyn CoreError> = self;
+        <dyn CoreError>::downcast_core(err).map_err(|s| unsafe {
+            // Reapply the `Send` marker.
+            core::mem::transmute::<Box<dyn CoreError>, Box<dyn CoreError + Send>>(s)
+        })
+    }
+}
+
+impl dyn CoreError + Send + Sync {
+    #[inline]
+    /// Attempts to downcast the box to a concrete type.
+    pub fn downcast_core<T: CoreError + 'static>(self: Box<Self>) -> Result<Box<T>, Box<Self>> {
+        let err: Box<dyn CoreError> = self;
+        <dyn CoreError>::downcast_core(err).map_err(|s| unsafe {
+            // Reapply the `Send + Sync` marker.
+            core::mem::transmute::<Box<dyn CoreError>, Box<dyn CoreError + Send + Sync>>(s)
+        })
+    }
+}
+
+impl dyn CoreError {
+    #[inline]
+    /// Attempts to downcast the box to a concrete type.
+    pub fn downcast_core<T: CoreError + 'static>(
+        self: Box<Self>,
+    ) -> Result<Box<T>, Box<dyn CoreError>> {
+        if self.core_is_equal::<T>() {
+            unsafe {
+                let raw: *mut dyn CoreError = Box::into_raw(self);
+                Ok(Box::from_raw(raw as *mut T))
+            }
+        } else {
+            Err(self)
+        }
+    }
+}
+
 /// A struct representing an aborted instruction execution, with a message
 /// indicating the cause.
 #[wasm_bindgen]
@@ -30,7 +113,10 @@ impl PartialEq for RuntimeError {
 #[derive(Debug)]
 enum RuntimeErrorSource {
     Generic(String),
+    #[cfg(feature = "std")]
     User(Box<dyn Error + Send + Sync>),
+    #[cfg(feature = "core")]
+    User(Box<dyn CoreError + Send + Sync>),
     Js(JsValue),
 }
 
@@ -64,16 +150,27 @@ impl RuntimeError {
 
     /// Raises a custom user Error
     #[deprecated(since = "2.1.1", note = "return a Result from host functions instead")]
+    #[cfg(feature = "std")]
     pub(crate) fn raise(error: Box<dyn Error + Send + Sync>) -> ! {
         let error = Self::user(error);
         let js_error: JsValue = error.into();
         wasm_bindgen::throw_val(js_error)
     }
 
+    /// Raises a custom user Error
+    #[deprecated(since = "2.1.1", note = "return a Result from host functions instead")]
+    #[cfg(feature = "core")]
+    pub(crate) fn raise(error: Box<dyn CoreError + Send + Sync>) -> ! {
+        let error = Self::user(error);
+        let js_error: JsValue = error.into();
+        wasm_bindgen::throw_val(js_error)
+    }
+
     /// Creates a custom user Error.
     ///
     /// This error object can be passed through Wasm frames and later retrieved
     /// using the `downcast` method.
+    #[cfg(feature = "std")]
     pub fn user(error: Box<dyn Error + Send + Sync>) -> Self {
         match error.downcast::<Self>() {
             // The error is already a RuntimeError, we return it directly
@@ -84,6 +181,17 @@ impl RuntimeError {
         }
     }
 
+    #[cfg(feature = "core")]
+    pub fn user(error: Box<dyn CoreError + Send + Sync>) -> Self {
+        match error.downcast_core::<Self>() {
+            // The error is already a RuntimeError, we return it directly
+            Ok(runtime_error) => *runtime_error,
+            Err(error) => RuntimeError {
+                inner: Arc::new(RuntimeErrorSource::User(error)),
+            },
+        }
+    }
+
     /// Returns a reference the `message` stored in `Trap`.
     pub fn message(&self) -> String {
         format!("{}", self.inner)
@@ -93,7 +201,12 @@ impl RuntimeError {
     pub fn downcast<T: Error + 'static>(self) -> Result<T, Self> {
         match Arc::try_unwrap(self.inner) {
             // We only try to downcast user errors
+            #[cfg(feature = "std")]
             Ok(RuntimeErrorSource::User(err)) if err.is::<T>() => Ok(*err.downcast::<T>().unwrap()),
+            #[cfg(feature = "core")]
+            Ok(RuntimeErrorSource::User(err)) if (*err).core_is_equal::<T>() => {
+                Ok(*err.downcast_core::<T>().unwrap())
+            }
             Ok(inner) => Err(Self {
                 inner: Arc::new(inner),
             }),
@@ -104,7 +217,10 @@ impl RuntimeError {
     /// Returns true if the `RuntimeError` is the same as T
     pub fn is<T: Error + 'static>(&self) -> bool {
         match self.inner.as_ref() {
+            #[cfg(feature = "std")]
             RuntimeErrorSource::User(err) => err.is::<T>(),
+            #[cfg(feature = "core")]
+            RuntimeErrorSource::User(err) => (*err).core_is_equal::<T>(),
             _ => false,
         }
     }
@@ -125,6 +241,7 @@ impl fmt::Display for RuntimeError {
     }
 }
 
+#[cfg(feature = "std")]
 impl std::error::Error for RuntimeError {
     fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
         match self.inner.as_ref() {

lib/compiler/src/engine/trap/error.rs

@@ -12,12 +12,19 @@ pub struct RuntimeError {
     inner: Arc<RuntimeErrorInner>,
 }
 
+pub trait CoreError: fmt::Debug + fmt::Display + core::any::Any {}
+
+impl<T: fmt::Debug + fmt::Display + core::any::Any> CoreError for T {}
+
 /// The source of the `RuntimeError`.
 #[derive(Debug)]
 enum RuntimeErrorSource {
     Generic(String),
     OutOfMemory,
+    #[cfg(feature = "std")]
     User(Box<dyn Error + Send + Sync>),
+    #[cfg(feature = "core")]
+    User(Box<dyn CoreError + Send + Sync>),
     Trap(TrapCode),
 }
 
@@ -110,6 +117,7 @@ impl RuntimeError {
     ///
     /// This error object can be passed through Wasm frames and later retrieved
     /// using the `downcast` method.
+    #[cfg(feature = "std")]
     pub fn user(error: Box<dyn Error + Send + Sync>) -> Self {
         match error.downcast::<Self>() {
             // The error is already a RuntimeError, we return it directly
@@ -126,6 +134,27 @@ impl RuntimeError {
         }
     }
 
+    /// Creates a custom user Error.
+    ///
+    /// This error object can be passed through Wasm frames and later retrieved
+    /// using the `downcast` method.
+    #[cfg(feature = "core")]
+    pub fn user(error: Box<dyn CoreError + Send + Sync>) -> Self {
+        match error.downcast::<Self>() {
+            // The error is already a RuntimeError, we return it directly
+            Ok(runtime_error) => *runtime_error,
+            Err(error) => {
+                let info = FRAME_INFO.read().unwrap();
+                Self::new_with_trace(
+                    &info,
+                    None,
+                    RuntimeErrorSource::User(error),
+                    Backtrace::new_unresolved(),
+                )
+            }
+        }
+    }
+
     fn new_with_trace(
         info: &GlobalFrameInfo,
         trap_pc: Option<usize>,