feat: resolve npm module type with loader option

deno.json

@@ -8,17 +8,18 @@
   "imports": {
     "@deno/cache-dir": "jsr:@deno/cache-dir@^0.8.0",
     "@deno/info": "./modules/deno/info.ts",
+    "@miyauci/esbuild-deno-specifier": "./src/mod.ts",
     "@miyauci/format": "jsr:@miyauci/format@^1.1.0",
     "@miyauci/node-esm-resolver": "jsr:@miyauci/node-esm-resolver@1.0.0-beta.8",
+    "@std/collections": "jsr:@std/collections@^0.224.2",
     "@std/expect": "jsr:@std/expect@^0.224.2",
     "@std/fs": "jsr:@std/fs@^0.229.1",
     "@std/log": "jsr:@std/log@^0.224.1",
     "@std/path": "jsr:@std/path@^0.225.1",
     "@std/testing": "jsr:@std/testing@^0.224.0",
     "@std/url": "jsr:@std/url@^0.224.0",
     "@unional/path-equal": "jsr:@unional/path-equal@^1.2.5",
-    "esbuild": "npm:esbuild@^0.21.4",
-    "@miyauci/esbuild-deno-specifier": "./src/mod.ts"
+    "esbuild": "npm:esbuild@^0.21.4"
   },
   "exports": "./src/mod.ts"
 }

src/load.ts

@@ -1,18 +1,19 @@
-import type { OnLoadResult } from "esbuild";
+import type { Loader, OnLoadResult } from "esbuild";
 import * as Path from "@std/path/dirname";
 import { dirname } from "@std/url/dirname";
 import { toFileUrl } from "@std/path/to-file-url";
 import { fromFileUrl } from "@std/path/from-file-url";
 import type { PluginData } from "./types.ts";
-import { mediaTypeToLoader } from "./utils.ts";
+import { mediaTypeToLoader, resolveLongestExt } from "./utils.ts";
 
 export async function loadDataURL(
   url: URL,
   pluginData: PluginData,
 ): Promise<OnLoadResult> {
   const result = await fetch(url);
   const contents = await result.text();
-  const loader = mediaTypeToLoader(pluginData.mediaType);
+  const loader = pluginData.mediaType &&
+    mediaTypeToLoader(pluginData.mediaType);
 
   return { contents, loader };
 }
@@ -21,10 +22,14 @@ export async function loadFileURL(
   url: URL,
   pluginData: PluginData,
   readFile: (url: URL) => Promise<string> | string,
+  loaders: Record<string, Loader>,
 ): Promise<OnLoadResult> {
   const contents = await readFile(url);
 
-  const loader = mediaTypeToLoader(pluginData.mediaType);
+  const loader = pluginData.mediaType
+    ? mediaTypeToLoader(pluginData.mediaType)
+    : resolveLongestExt(fromFileUrl(url), loaders) ?? "default";
+
   const resolveDir = fromFileUrl(dirname(url));
 
   return { contents, loader, pluginData, resolveDir };
@@ -48,7 +53,8 @@ export async function loadHttpURL(
   const fileUrl = toFileUrl(localPath);
   const contents = await readFile(fileUrl);
 
-  const loader = mediaTypeToLoader(pluginData.mediaType);
+  const loader = pluginData.mediaType &&
+    mediaTypeToLoader(pluginData.mediaType);
   const resolveDir = Path.dirname(localPath);
 
   return { contents, loader, pluginData, resolveDir };

src/modules/npm.ts

@@ -15,7 +15,6 @@ import { require } from "../npm/cjs/require.ts";
 import { assertModule, assertModuleEntry } from "./utils.ts";
 import type { Subpath } from "../types.ts";
 import { Msg } from "../constants.ts";
-import { fileFormat } from "../npm/cjs/file_format.ts";
 import { resolveSideEffects } from "../side_effects.ts";
 import { lookupPackageScope } from "../npm/cjs/lookup_package_scope.ts";
 
@@ -182,8 +181,6 @@ export async function toResolveResult(
       const finalURL = context.realURL
         ? (await context.realURL(url)) ?? url
         : url;
-      const format = await fileFormat(finalURL, context);
-      const mediaType = (format && formatToMediaType(format)) ?? "Unknown";
       const packageURL = await lookupPackageScope(finalURL, context);
 
       if (packageURL) {
@@ -196,15 +193,15 @@ export async function toResolveResult(
             fromFileUrl(finalURL),
           );
 
-          return { url: finalURL, mediaType, sideEffects };
+          return { url: finalURL, mediaType: undefined, sideEffects };
         }
       }
 
-      return { url: finalURL, mediaType, sideEffects: undefined };
+      return { url: finalURL, mediaType: undefined, sideEffects: undefined };
     }
 
     default: {
-      return { url, mediaType: "Unknown", sideEffects: undefined };
+      return { url, mediaType: undefined, sideEffects: undefined };
     }
   }
 }

src/modules/types.ts

@@ -16,7 +16,7 @@ export interface DependencyContext extends Context {
 
 export interface ResolveResult {
   url: URL;
-  mediaType: MediaType;
+  mediaType: MediaType | undefined;
   sideEffects: boolean | undefined;
 }
 

src/option.ts

@@ -1,4 +1,9 @@
-import { type BuildOptions, type ImportKind, type Platform } from "esbuild";
+import {
+  type BuildOptions,
+  type ImportKind,
+  type Loader,
+  type Platform,
+} from "esbuild";
 
 /**
  * @see https://esbuild.github.io/api/#resolve-extensions
@@ -26,6 +31,48 @@ const defaultMainFields = {
  */
 const defaultPlatform = "browser" satisfies Platform;
 
+/** Default map of extension and loader.
+ *
+ * @see https://esbuild.github.io/content-types/
+ */
+const defaultContentTypes = {
+  /**
+   * @see https://esbuild.github.io/content-types/#javascript
+   */
+  ".js": "js",
+  ".mjs": "js",
+  ".cjs": "js",
+
+  /**
+   * @see https://esbuild.github.io/content-types/#typescript
+   */
+  ".ts": "ts",
+  ".mts": "ts",
+  ".cts": "ts",
+
+  /**
+   * @see https://esbuild.github.io/content-types/#jsx
+   */
+  ".jsx": "jsx",
+  ".tsx": "tsx",
+
+  /**
+   * @see https://esbuild.github.io/content-types/#json
+   */
+  ".json": "json",
+
+  /**
+   * @see https://esbuild.github.io/content-types/#css
+   */
+  ".css": "css",
+  ".module.css": "local-css",
+
+  /**
+   * @see https://esbuild.github.io/content-types/#text
+   */
+  ".txt": "text",
+} satisfies Record<string, Loader>;
+
 export function normalizeResolveExtensions(
   resolveExtensions?: string[],
 ): string[] {
@@ -92,6 +139,15 @@ export function resolvePlatform(platForm: Platform): string | null {
   }
 }
 
+export function normalizeLoader(
+  loader?: Record<string, Loader>,
+): Record<string, Loader> {
+  return {
+    ...defaultContentTypes,
+    ...loader,
+  };
+}
+
 export type DependentBuildOptions = Pick<
   BuildOptions,
   | "platform"
@@ -101,4 +157,5 @@ export type DependentBuildOptions = Pick<
   | "logLevel"
   | "packages"
   | "absWorkingDir"
+  | "loader"
 >;

src/plugin.ts

@@ -16,6 +16,7 @@ import { loadDataURL, loadFileURL, loadHttpURL } from "./load.ts";
 import { GlobalStrategy, LocalStrategy } from "./strategy.ts";
 import { resolveReferrer } from "./referrer.ts";
 import { existDir, existFile, readFile, realURL } from "./io.ts";
+import { normalizeLoader } from "./option.ts";
 
 export interface DenoSpecifierPluginOptions {
   /** Enables or disables the use of a local node_modules folder for npm packages.
@@ -139,6 +140,8 @@ export function denoSpecifierPlugin(
         },
       );
 
+      const loader = normalizeLoader(build.initialOptions.loader);
+
       build.onLoad(
         { filter: /.*/, namespace: Namespace.DenoUrl },
         (args) => {
@@ -151,7 +154,7 @@ export function denoSpecifierPlugin(
               return loadHttpURL(null, pluginData, readStrict);
 
             case "file:":
-              return loadFileURL(url, pluginData, readStrict);
+              return loadFileURL(url, pluginData, readStrict, loader);
 
             case "data:":
               return loadDataURL(url, pluginData);

src/types.ts

@@ -3,7 +3,7 @@ import type { MediaType, Module, SourceFileInfo as Source } from "@deno/info";
 export interface PluginData {
   module: Module;
   source: Source;
-  mediaType: MediaType;
+  mediaType: MediaType | undefined;
 }
 
 export type Subpath = `.${string}`;

src/utils.ts

@@ -2,6 +2,8 @@ import { type MediaType } from "@deno/info";
 import { toFileUrl } from "@std/path/to-file-url";
 import { join } from "@std/url/join";
 import { getLogger } from "@std/log/get-logger";
+import { runningReduce } from "@std/collections/running-reduce";
+import { extname } from "@std/path/extname";
 import { type Logger } from "@std/log/logger";
 
 import type { Loader } from "esbuild";
@@ -102,3 +104,40 @@ export function createNpmRegistryURL(denoDir: string): URL {
 export function createPjsonURL(packageURL: URL | string): URL {
   return join(packageURL, "package.json");
 }
+
+/**
+ * @param path
+ * @returns
+ */
+export function* splitExts(path: string): Generator<string> {
+  const ext = extname(path);
+
+  if (!ext) return;
+
+  yield ext;
+
+  path = path.slice(0, path.length - ext.length);
+
+  yield* splitExts(path);
+}
+
+/** Resolve path extension with longest match. */
+export function resolveLongestExt<T>(
+  path: string,
+  record: Record<string, T>,
+): T | undefined {
+  const allExts = getAllExtensions(path);
+
+  for (const ext of allExts) if (ext in record) return record[ext];
+}
+
+export function getAllExtensions(path: string): string[] {
+  const partOfExts = [...splitExts(path)];
+  const allExts = runningReduce(
+    partOfExts,
+    (acc, current) => current + acc,
+    "",
+  ).reverse();
+
+  return allExts;
+}