Fix the webidl-tests crate

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

@@ -3,6 +3,7 @@ use crate::descriptor::{Descriptor, VectorKind};
 use crate::{Bindgen, EncodeInto, OutputMode};
 use failure::{bail, Error, ResultExt};
 use std::collections::{HashMap, HashSet};
+use std::env;
 use walrus::{MemoryId, Module};
 use wasm_bindgen_wasm_interpreter::Interpreter;
 
@@ -2797,11 +2798,14 @@ impl<'a, 'b> SubContext<'a, 'b> {
         // module syntax in the snippet to a CommonJS module, which is in theory
         // not that hard but is a chunk of work to do.
         if is_local_snippet && self.cx.config.mode.nodejs() {
-            bail!(
-                "local JS snippets are not supported with `--nodejs`; \
-                 see rustwasm/rfcs#6 for more details, but this restriction \
-                 will be lifted in the future"
-            );
+            // have a small unergonomic escape hatch for our webidl-tests tests
+            if env::var("WBINDGEN_I_PROMISE_JS_SYNTAX_WORKS_IN_NODE").is_err() {
+                bail!(
+                    "local JS snippets are not supported with `--nodejs`; \
+                     see rustwasm/rfcs#6 for more details, but this restriction \
+                     will be lifted in the future"
+                );
+            }
         }
 
         // Similar to `--no-modules`, only allow vendor prefixes basically for web

crates/webidl-tests/build.rs

@@ -21,14 +21,13 @@ fn main() {
 
         let out_file = out_dir.join(path.file_name().unwrap()).with_extension("rs");
 
-        let js_file = path.with_extension("js").canonicalize().unwrap();
         generated_rust.push_str(&format!(
             r#"
             pub mod import_script {{
                 use wasm_bindgen::prelude::*;
                 use wasm_bindgen_test::*;
 
-                #[wasm_bindgen(module = r"{}")]
+                #[wasm_bindgen(module = "/{}.js")]
                 extern "C" {{
                     fn not_actually_a_function{1}(x: &str);
                 }}
@@ -41,7 +40,7 @@ fn main() {
                 }}
             }}
         "#,
-            js_file.display(),
+            path.file_stem().unwrap().to_str().unwrap(),
             i
         ));