feat: Add exposeWasm option

README.md

@@ -19,6 +19,8 @@ to breaking changes, although any such changes will follow semantic versioning.
 - [Requirements & basic setup](#requirements--basic-setup)
 - [The transformation](#the-transformation)
 - [The plugin config](#the-plugin-config)
+  - [Filtering](#filtering)
+  - [Raw wasm output](#raw-wasm-output)
 
 <!-- END doctoc generated TOC please keep comment here to allow auto update -->
 
@@ -126,6 +128,13 @@ interface Filter {
 
 interface Opts {
 
+  /**
+   * When set to true, adds a __getWasm() function to the import() response which returns what the original
+   * init function returned
+   * @default false
+   */
+  exposeWasm?: boolean;
+
   /**
    * JS source files to look for dynamic imports in.
    * @default {include: /\.[jt]sx?$/}
@@ -146,7 +155,22 @@ interface Opts {
 }
 ```
 
+## Filtering
+
 There are two sets of files to match. Using the `my_lib` example from earlier,
 
 - `wasmFilter` should match `my_lib.js`
 - `jsFilter` should match files that'll contain the dynamic `import()`s
+
+## Raw wasm output
+
+By default, the response of the original init function is hidden. You can turn the `exposeWasm` option on to append
+a `__getWasm` function to the module which will return it. If you're using Typescript, you can correct your typings by
+adding the following to your Rust source files (constant name doesn't matter):
+
+```rust
+#[wasm_bindgen(typescript_custom_section)]
+const TS_APPEND_CONTENT: &'static str = r#"
+export function __getWasm(): InitOutput;
+"#;
+```

package.json

@@ -32,6 +32,7 @@
     "@alorel/rollup-plugin-copy": "^1.0.2",
     "@alorel/rollup-plugin-copy-pkg-json": "^1.0.3",
     "@alorel/rollup-plugin-dts": "^2.0.1",
+    "@rollup/plugin-alias": "^3.1.2",
     "@rollup/plugin-node-resolve": "^13.0.0",
     "@rollup/plugin-replace": "^2.4.2",
     "@rollup/pluginutils": "^4.1.0",

projects/core/autoinit-wasm-import.js

@@ -1,11 +1,24 @@
-export default function autoinitWasmImport(imp, url) {
-  return Promise
-    .all([
-      imp,
-      fetch(url)
-    ])
-    .then(function wasmImportInitialiser([wasmModule, response]) {
-      return wasmModule.default(response)
-        .then(() => wasmModule);
-    });
+function createGetter(initResponse) {
+  const getter = {};
+  Object.defineProperty(getter, '__getWasm', {
+    value: function __getWasm() {
+      return initResponse;
+    }
+  });
+
+  return getter;
+}
+
+/**
+ * @param {Promise<any>} imp - The dynamic import
+ * @param {string} url - The wasm file's URL
+ * @param {boolean} exposeWasm - Whether to expose the init function's response or not
+ */
+export default async function autoinitWasmImport(imp, url, exposeWasm) {
+  const [wasmModule, fetchResponse] = await Promise.all([imp, fetch(url)]);
+  const initResponse = await wasmModule.default(fetchResponse);
+
+  return exposeWasm ?
+    Object.assign(createGetter(initResponse), wasmModule) :
+    wasmModule;
 }