actually use the --files config

This was an oversight in the v18 rewrite.

Fix: #922

src/run/src/list.ts

@@ -43,6 +43,8 @@ export const list = async (
 ) => {
   const saveList: Set<string> = new Set(await readSave(config))
 
+  if (args.length === 0) args = config.get('files') || []
+
   const ignore = [alwaysExcludePattern]
   if (values.exclude) ignore.push(...values.exclude)
 

src/run/test/list.ts

@@ -85,7 +85,7 @@ t.test('list some test files', async t => {
 
   const sortedLog = () =>
     logs
-      .args()[0][0]
+      .args()[0]?.[0]
       .trim()
       .split('\n')
       .sort((a: string, b: string) => a.localeCompare(b, 'en'))
@@ -115,6 +115,25 @@ t.test('list some test files', async t => {
     ])
   })
 
+  t.test('config files', async t => {
+    const orig = mainConfig.config.get
+    t.capture(
+      mainConfig.config,
+      'get',
+      (k: Parameters<typeof mainConfig.config.get>[0]) => {
+        if (k === 'files') return ['src/*.spec.js', 'test/*.*js']
+        return orig.call(mainConfig.config, k)
+      }
+    )
+    await list([], mainConfig.config)
+    t.strictSame(sortedLog(), [
+      'src/index.spec.js',
+      'src/test.spec.js',
+      'test/foo.cjs',
+      'test/foo.mjs',
+    ])
+  })
+
   t.test('specific files, noent, and stdin', async t => {
     await list(
       ['src/test.spec.js', '/dev/stdin', '-', 'enoent not exists'],