only emit wasm runtime code for bundles containing wasm

sokra · sokra · commit 8363773f3fb9 · 2017-11-21T12:57:40.000+01:00
diff --git a/lib/Chunk.js b/lib/Chunk.js
@@ -579,6 +579,24 @@ class Chunk {
 		};
 	}
 
+	hasModuleInGraph(filterFn) {
+		const chunksProcessed = new Set();
+		const queue = [this];
+
+		while(queue.length > 0) {
+			const chunk = queue.pop();
+			if(chunk.getModules().some(filterFn))
+				return true;
+			for(const next of chunk.chunksIterable) {
+				if(!chunksProcessed.has(next)) {
+					chunksProcessed.add(next);
+					queue.push(next);
+				}
+			}
+		}
+		return false;
+	}
+
 	sortModules(sortByFn) {
 		this._modules.sortWith(sortByFn || sortById);
 	}
diff --git a/lib/web/FetchCompileWasmMainTemplatePlugin.js b/lib/web/FetchCompileWasmMainTemplatePlugin.js
@@ -8,6 +8,8 @@ class FetchCompileWasmMainTemplatePlugin {
 
 	apply(mainTemplate) {
 		mainTemplate.plugin("local-vars", (source, chunk) => {
+			if(!chunk.hasModuleInGraph(m => m.type.startsWith("webassembly")))
+				return source;
 			return mainTemplate.asString([
 				source,
 				"",
@@ -69,6 +71,8 @@ class FetchCompileWasmMainTemplatePlugin {
 			]);
 		});
 		mainTemplate.plugin("require-extensions", (source, chunk) => {
+			if(!chunk.hasModuleInGraph(m => m.type.startsWith("webassembly")))
+				return source;
 			return mainTemplate.asString([
 				source,
 				"",
