fix: 🐛 fix config handling and default file loader on windows

README.md

@@ -112,8 +112,13 @@ Overwrite the default file loader.
 This can be useful if you want to modify or process the file before generating srcsets.
 For example, you could change the fill color in an SVG from black to white:
 ```ts
+import { stripSrcsetQuery } from 'vite-plugin-srcset';
+import { normalizePath } from 'vite';
+
 async function loadFile(id: string) {
-    const fsPath = new URL(id, import.meta.url).pathname; // id includes all search params (including srcset), which we don't care about here
+    // id includes all search params (including srcset), which we don't care about here
+    // in this example we'll strip the `srcset` as well as the `dark` query
+    const fsPath = normalizePath(stripSrcsetQuery(stripSrcsetQuery(id, 'dark')));
     let text = await readFile(fsPath, 'utf-8');
     text = text.replaceAll('fill="#000000"', 'fill="#FFFFFF"');
     return { contents: Buffer.from(text, 'utf-8') };

src/index.ts

@@ -1,4 +1,4 @@
-import { createFilter, type Plugin } from 'vite';
+import { createFilter, normalizePath, type Plugin } from 'vite';
 import { ESLiteral, toESString } from './utils/toESString';
 import { readFile } from 'node:fs/promises';
 import { parse } from 'node:path';
@@ -12,10 +12,21 @@ export interface ModuleExport {
     // all: Record<ImageType, Record<number, string>>;
 }
 
+export function stripSrcsetQuery(id: string, query = 'srcset'): string {
+    const url = new URL(id, import.meta.url);
+    const oldSearch = url.search;
+    url.searchParams.delete(query);
+    const newSearch = url.search;
+
+    return id.replace(oldSearch, newSearch);
+}
+
 const DEFAULT_WIDTHS = [64, 128, 256, 512, 1024];
 const DEFAULT_FORMATS = { png: true, webp: true };
-const DEFAULT_FILE_LOADER = (id: string): Promise<{ contents: Uint8Array }> =>
-    readFile(new URL(id, import.meta.url).pathname).then((contents) => ({ contents }));
+const DEFAULT_FILE_LOADER = (id: string): Promise<{ contents: Uint8Array }> => {
+    const path = normalizePath(stripSrcsetQuery(id));
+    return readFile(path).then((contents) => ({ contents }));
+};
 
 export async function renderImg(
     original: Uint8Array,
@@ -121,7 +132,9 @@ export default function srcsetPlugin(...options: SrcsetPluginConfig): Plugin {
             url.searchParams.delete('srcset');
             const idWithoutParams = url.pathname;
 
-            const config = findConfig(url.pathname + url.search);
+            const normalizedId = normalizePath(stripSrcsetQuery(id));
+
+            const config = findConfig(normalizedId);
 
             const { contents: original } = await config.loadFile.call(this, id);