feat: override fetch to use file service if possible

package.json

@@ -258,6 +258,7 @@
     "@octokit/rest": "^19.0.11",
     "@rollup/plugin-commonjs": "^25.0.1",
     "@rollup/plugin-dynamic-import-vars": "^2.0.3",
+    "@rollup/plugin-inject": "^5.0.3",
     "@rollup/plugin-json": "^6.0.0",
     "@rollup/plugin-node-resolve": "^15.1.0",
     "@rollup/plugin-replace": "^5.0.2",
@@ -301,11 +302,11 @@
     "vscode-textmate": "^9.0.0",
     "xterm": "5.2.1",
     "xterm-addon-canvas": "0.4.0",
+    "xterm-addon-image": "0.4.1",
     "xterm-addon-search": "0.12.0",
     "xterm-addon-serialize": "0.10.0",
     "xterm-addon-unicode11": "0.5.0",
     "xterm-addon-webgl": "0.15.0",
-    "xterm-addon-image": "0.4.1",
     "yauzl": "^2.10.0"
   },
   "overrides": {

rollup/rollup.config.ts

@@ -12,6 +12,7 @@ import externalAssets from 'rollup-plugin-external-assets'
 import globImport from 'rollup-plugin-glob-import'
 import terser from '@rollup/plugin-terser'
 import styles from 'rollup-plugin-styles'
+import inject from '@rollup/plugin-inject'
 import * as fs from 'fs'
 import * as path from 'path'
 import { fileURLToPath } from 'url'
@@ -452,6 +453,10 @@ export default (args: Record<string, string>): rollup.RollupOptions[] => {
     }],
     input,
     plugins: [
+      inject({
+        fetch: path.resolve('src/custom-fetch.ts'),
+        include: [/extHostExtensionService/]
+      }),
       commonjs(),
       extensionDirectoryPlugin({
         include: `${DEFAULT_EXTENSIONS_PATH}/**/*`,

src/custom-fetch.ts

@@ -0,0 +1,37 @@
+import { IFileService } from 'vs/platform/files/common/files'
+import { StandaloneServices } from 'vs/editor/standalone/browser/standaloneServices'
+import { URI } from 'vs/base/common/uri'
+import { unsupported } from './tools'
+
+const fetch: typeof window.fetch = async (input: RequestInfo | URL, init?: RequestInit) => {
+  if (typeof input === 'string') {
+    const uri = URI.parse(input)
+    const fileService = StandaloneServices.get(IFileService)
+    if (fileService.hasProvider(uri)) {
+      const response: Response = {
+        get headers () { return unsupported() },
+        ok: true,
+        redirected: false,
+        status: 200,
+        statusText: 'Ok',
+        type: 'basic',
+        url: input,
+        clone: unsupported,
+        get body () { return unsupported() },
+        bodyUsed: false,
+        arrayBuffer: unsupported,
+        blob: unsupported,
+        formData: unsupported,
+        json: unsupported,
+        text: async function (): Promise<string> {
+          const content = await fileService.readFile(URI.parse(input))
+          return content.value.toString()
+        }
+      }
+      return response
+    }
+  }
+  return window.fetch(input, init)
+}
+
+export default fetch