update fetch to take a string parameter

crates/cli/src/bin/wasm2es6js.rs

@@ -22,7 +22,7 @@ Options:
     -o --output FILE        File to place output in
     --typescript            Output a `*.d.ts` file next to the JS output
     --base64                Inline the wasm module using base64 encoding
-    --fetch                 Load module via `fetch()` instead of default webpack implementation
+    --fetch PATH            Load module by passing the PATH argument to `fetch()`
 
 Note that this is not intended to produce a production-ready output module
 but rather is intended purely as a temporary \"hack\" until it's standard in
@@ -34,7 +34,7 @@ struct Args {
     flag_output: Option<PathBuf>,
     flag_typescript: bool,
     flag_base64: bool,
-    flag_fetch: bool,
+    flag_fetch: Option<String>,
     arg_input: PathBuf,
 }
 
@@ -43,7 +43,7 @@ fn main() {
         .and_then(|d| d.deserialize())
         .unwrap_or_else(|e| e.exit());
 
-    if !args.flag_base64 && !args.flag_fetch {
+    if !args.flag_base64 && !args.flag_fetch.is_some() {
         panic!("unfortunately only works right now with base64 or fetch");
     }
 
@@ -53,7 +53,7 @@ fn main() {
 
     let object = wasm_bindgen_cli_support::wasm2es6js::Config::new()
         .base64(args.flag_base64)
-        .fetch(args.flag_fetch, &args.arg_input)
+        .fetch(args.flag_fetch)
         .generate(&wasm)
         .expect("failed to parse wasm");