fix(js): restore static wasm URL for bundler asset detection

packages/js/package.json

@@ -43,7 +43,8 @@
     "./package.json": "./package.json"
   },
   "files": [
-    "dist"
+    "dist",
+    "CHANGELOG.md"
   ],
   "sideEffects": [
     "**/*.wasm",

packages/js/vite.config.js

@@ -61,25 +61,6 @@ if (!T) {
   throw new Error(`Unknown TARGET "${TARGET}". Expected one of: ${Object.keys(TARGETS).join(", ")}`);
 }
 
-/**
- * Vite inlines `new URL('x.wasm', import.meta.url)` as a data URL in lib mode
- *  and ignores assetsInlineLimit. Hoisting the literal defeats the static
- *  analysis, leaving a real runtime URL resolution against the sibling file.
- */
-function preventWasmInlining() {
-  return {
-    name: "img2num:prevent-wasm-inlining",
-    enforce: "pre",
-    transform(code, id) {
-      if (!id.includes("build-wasm") || !T.copyWasm) return null;
-      if (!code.includes("import.meta.url")) return null;
-
-      const patched = code.replace(/new URL\((["'])(img2num\.wasm)\1,\s*import\.meta\.url\)/g, 'new URL(globalThis.__IMG2NUM_WASM_NAME__ ??= "$2", import.meta.url)');
-      return patched === code ? null : { code: patched, map: null };
-    },
-  };
-}
-
 /**
  * Copies the emitted .wasm into dist/<target>/ after the bundle is written.
  */
@@ -103,6 +84,76 @@ function copyWasmPlugin() {
   };
 }
 
+/**
+ * Ships a bundler-detectable wasm URL in the published output.
+ *
+ * Problem: Vite's lib mode inlines `new URL("x.wasm", import.meta.url)` as a
+ * data URL and ignores assetsInlineLimit. But downstream bundlers (Vite,
+ * webpack 5, Rollup, Parcel) rely on that exact literal form to detect,
+ * emit, and rewrite the wasm asset in *consumer* builds.
+ *
+ * Solution, in two phases:
+ *   1. transform: mangle the literal into a non-static expression so
+ *      lib-mode asset analysis can't inline it.
+ *   2. generateBundle: after analysis is done, restore a bundler-detectable
+ *      form in the emitted chunk. The restored form is a TERNARY, not the
+ *      bare literal: the false branch is the exact literal (which consumer
+ *      bundlers detect and rewrite), while the true branch preserves
+ *      `globalThis.__IMG2NUM_WASM_NAME__` as a runtime override for exotic
+ *      setups (e.g. CDN-hosted wasm). Do not "simplify" the ternary away --
+ *      collapsing it to the literal silently kills the override.
+ *
+ * LOAD-BEARING CONSTRAINT: the mangled sentinel must be valid syntax at
+ * build.target (es2020). Do NOT use `??=` or other ES2021+ operators here --
+ * they get transpiled before generateBundle runs, the restore match fails
+ * silently, and the published chunk ships a non-static URL (the 0.4.0 bug).
+ * `||` is safe at es2020.
+ */
+function wasmUrlPlugin() {
+  const LITERAL = 'new URL("img2num.wasm", import.meta.url)';
+  const MANGLED = 'new URL(globalThis.__IMG2NUM_WASM_NAME__ || "img2num.wasm", import.meta.url)';
+  const WASM_NAME = "globalThis.__IMG2NUM_WASM_NAME__";
+  // Override wins when set; otherwise the literal branch is what consumer
+  // bundlers statically detect. Bundlers match the expression node, so the
+  // literal being inside a ternary branch does not defeat detection.
+  const RESTORED = `(${WASM_NAME} ? new URL(${WASM_NAME}, import.meta.url) : ${LITERAL})`;
+
+  // The pattern only exists in the ES6 web glue; node glue resolves via
+  // __dirname and standalone glue via document.currentScript. Restricting to
+  // the browser target makes that a structural guarantee instead of a
+  // coincidence of glue contents.
+  if (TARGET !== "browser") return { name: "img2num:wasm-url" };
+
+  return {
+    name: "img2num:wasm-url",
+    enforce: "pre",
+    transform(code, id) {
+      if (!id.includes("build-wasm")) return null;
+      if (!code.includes("import.meta.url")) return null;
+
+      const patched = code.replace(/new URL\((["'])(img2num\.wasm)\1,\s*import\.meta\.url\)/g, MANGLED);
+      return patched === code ? null : { code: patched, map: null };
+    },
+    generateBundle(_, bundle) {
+      // Tolerant match: quote style and whitespace may be normalized by the
+      // bundler even when the expression itself survives.
+      const mangledRe = /new URL\(\s*globalThis\.__IMG2NUM_WASM_NAME__\s*\|\|\s*(["'])img2num\.wasm\1\s*,\s*import\.meta\.url\s*\)/g;
+
+      for (const chunk of Object.values(bundle)) {
+        if (chunk.type !== "chunk") continue;
+        chunk.code = chunk.code.replace(mangledRe, RESTORED);
+      }
+
+      // Guard: the browser ES build must ship the bundler-detectable literal.
+      // Fails the build loudly instead of shipping a consumer-breaking chunk.
+      const hasLiteral = Object.values(bundle).some((c) => c.type === "chunk" && c.code.includes(LITERAL));
+      if (!hasLiteral) {
+        throw new Error("[img2num] wasm URL literal missing from browser bundle -- consumers' bundlers won't detect the asset.");
+      }
+    },
+  };
+}
+
 const FILE_NAMES = {
   es: "img2num.js",
   cjs: "img2num.cjs",
@@ -111,7 +162,7 @@ const FILE_NAMES = {
 };
 
 export default defineConfig({
-  plugins: [preventWasmInlining(), copyWasmPlugin()],
+  plugins: [wasmUrlPlugin(), copyWasmPlugin()],
 
   build: {
     outDir: T.outDir ?? `dist/${TARGET}`,