Super primitive BomPrependingPlugin

BomPlugin.js

const pluginMeta = { name: "BomPlugin" };

class BomPlugin {
  constructor(encoding = "\ufeff") {
    this.encoding = encoding;
  }
  apply(/** @type {import("webpack/lib/Compiler")}*/ compiler) {
    compiler.hooks.compilation.tap(pluginMeta, (
      /** @type {import("webpack/lib/Compilation")}*/ compilation,
      params
    ) => {
      compilation.hooks.afterOptimizeAssets.tap(pluginMeta, assets => {
        for (let fileName in assets) {
          if (fileName.endsWith(".js")) {
            const bomEncodedAsset = new ConcatSource(
              this.encoding, // BOM for UTF-8 and UTF-16
              assets[fileName]
            );

            assets[fileName] = bomEncodedAsset;
          }
        }
      });
    });
  }
}
}