perf: resolved modules caching

src/shims/fibers.d.ts

@@ -2,8 +2,3 @@ declare namespace fibers {
   // eslint-disable-next-line @typescript-eslint/no-unused-vars
   class Fiber {}
 }
-
-declare module "fibers" {
-  const fiber: fibers.Fiber;
-  export = fiber;
-}

src/shims/less.d.ts

@@ -1,7 +1,7 @@
 declare namespace less {
   interface File {
-    contents?: string;
-    filename?: string;
+    contents: string;
+    filename: string;
   }
 
   class AbstractFileManager {
@@ -66,8 +66,3 @@ declare namespace less {
     render(input: string, options?: Options): Promise<RenderOutput>;
   }
 }
-
-declare module "less" {
-  const less: less.Less;
-  export = less;
-}

src/shims/sass.d.ts

@@ -43,15 +43,6 @@ declare namespace sass {
 
   interface Sass {
     render: (options: Options, callback: Callback) => void;
+    renderSync: (options: Options) => Result;
   }
 }
-
-declare module "sass" {
-  const sass: sass.Sass;
-  export = sass;
-}
-
-declare module "node-sass" {
-  const sass: sass.Sass;
-  export = sass;
-}

src/shims/stylus.d.ts

@@ -1,18 +1,20 @@
 declare namespace stylus {
+  type Callback = (err: Error, css: string) => void;
+
+  interface SourceMapOptions {
+    comment?: boolean;
+    inline?: boolean;
+    sourceRoot?: string;
+    basePath?: string;
+  }
+
   interface Options {
     imports?: string[];
     paths?: string[];
     filename?: string;
-    sourcemap?: {
-      comment?: boolean;
-      inline?: boolean;
-      sourceRoot?: string;
-      basePath?: string;
-    };
+    sourcemap?: SourceMapOptions;
   }
 
-  type Callback = (err: Error, css: string) => void;
-
   interface Renderer {
     render(callback: Callback): void;
     deps(): string[];
@@ -32,8 +34,3 @@ declare namespace stylus {
     (code: string, options?: Options): Renderer;
   }
 }
-
-declare module "stylus" {
-  const stylus: stylus.Stylus;
-  export = stylus;
-}

src/utils/load-module.ts

@@ -1,34 +1,21 @@
-import resolveAsync from "./resolve-async";
+/* eslint-disable @typescript-eslint/no-var-requires */
+import { sync as resolveSync } from "resolve";
 
-export interface ModuleImportMap extends Record<string, unknown> {
-  sass: sass.Sass;
-  "node-sass": sass.Sass;
-  fibers: fibers.Fiber;
-  less: less.Less;
-  stylus: stylus.Stylus;
-}
-
-export default async <T extends keyof ModuleImportMap>(
-  moduleId: T,
-  basedir = process.cwd(),
-): Promise<ModuleImportMap[T] | undefined> => {
-  if (typeof moduleId !== "string") return;
-
-  try {
-    return require(moduleId) as ModuleImportMap[T];
-  } catch {
-    /* noop */
-  }
+const loaded: Record<string, unknown> = {};
+export default function (moduleId: string, basedir = process.cwd()): unknown | undefined {
+  if (loaded[moduleId]) return loaded[moduleId];
+  if (loaded[moduleId] === null) return;
 
   try {
-    return require(await resolveAsync(moduleId, { basedir })) as ModuleImportMap[T];
-  } catch {
-    /* noop */
-  }
-
-  try {
-    return require(await resolveAsync(`./${moduleId}`, { basedir })) as ModuleImportMap[T];
+    try {
+      loaded[moduleId] = require(resolveSync(moduleId, { basedir })) as unknown;
+    } catch {
+      loaded[moduleId] = require(resolveSync(`./${moduleId}`, { basedir })) as unknown;
+    }
   } catch {
+    loaded[moduleId] = null;
     return;
   }
-};
+
+  return loaded[moduleId];
+}