feat: support .config dir (#136)

Author: pi0

README.md

@@ -13,7 +13,8 @@ c12 (pronounced as /siːtwelv/, like c-twelve) is a smart configuration loader.
 ## ✅ Features
 
 - `.js`, `.ts`, `.cjs`, `.mjs` config loader with [unjs/jiti](https://github.com/unjs/jiti)
-- `.json`, `.json5` and `.jsonc` config support.
+- `.json`, `.json5` and `.jsonc` config support
+- `.config/` directory support following [config dir proposal](https://github.com/pi0/config-dir)
 - `.rc` config support with [unjs/rc9](https://github.com/unjs/rc9)
 - `.env` support with [dotenv](https://www.npmjs.com/package/dotenv)
 - Multiple sources merged with [unjs/defu](https://github.com/unjs/defu)

src/loader.ts

@@ -298,11 +298,16 @@ async function resolveConfig<
     source = cloned.dir;
   }
 
-  // Try resolving as npm package
-  if (NPM_PACKAGE_RE.test(source)) {
+  // Util to try resolving a module
+  const tryResolve = (id: string) => {
     try {
-      source = options.jiti!.resolve(source, { paths: [options.cwd!] });
+      return options.jiti!.resolve(id, { paths: [options.cwd!] });
     } catch {}
+  };
+
+  // Try resolving as npm package
+  if (NPM_PACKAGE_RE.test(source)) {
+    source = tryResolve(source) || source;
   }
 
   // Import from local fs
@@ -314,19 +319,22 @@ async function resolveConfig<
   }
   const res: ResolvedConfig<T, MT> = {
     config: undefined as unknown as T,
+    configFile: undefined,
     cwd,
     source,
     sourceOptions,
   };
-  try {
-    res.configFile = options.jiti!.resolve(resolve(cwd, source), {
-      paths: [cwd],
-    });
-  } catch {}
+
+  res.configFile =
+    tryResolve(resolve(cwd, source)) ||
+    tryResolve(resolve(cwd, ".config", source.replace(/\.config$/, ""))) ||
+    tryResolve(resolve(cwd, ".config", source)) ||
+    source;
 
   if (!existsSync(res.configFile!)) {
     return res;
   }
+
   if (res.configFile!.endsWith(".jsonc")) {
     const { parse } = await import("jsonc-parser");
     res.config = parse(await readFile(res.configFile!, "utf8"));

test/fixture/test.config.ts test/fixture/.config/test.ts

@@ -144,7 +144,7 @@ describe("c12", () => {
               "secondary": "theme_secondary",
             },
           },
-          "configFile": "<path>/fixture/theme/test.config.json5",
+          "configFile": "<path>/fixture/theme/.config/test.config.json5",
           "cwd": "<path>/fixture/theme",
           "meta": {},
           "source": "test.config",