feat/issue-1398: added support for custom configuration

lib/makeCmdTasks.js

@@ -1,7 +1,8 @@
 import debug from 'debug'
 
 import { configurationError } from './messages.js'
-import { resolveTaskFn } from './resolveTaskFn.js'
+import { makeErr, resolveTaskFn } from './resolveTaskFn.js'
+import { getInitialState } from './state.js'
 
 const debugLog = debug('lint-staged:makeCmdTasks')
 
@@ -31,20 +32,44 @@ export const makeCmdTasks = async ({ commands, cwd, files, gitDir, shell, verbos
     const resolvedArray = Array.isArray(resolved) ? resolved : [resolved] // Wrap non-array command as array
 
     for (const command of resolvedArray) {
-      // If the function linter didn't return string | string[]  it won't work
-      // Do the validation here instead of `validateConfig` to skip evaluating the function multiple times
-      if (isFn && typeof command !== 'string') {
-        throw new Error(
-          configurationError(
-            '[Function]',
-            'Function task should return a string or an array of strings',
-            resolved
+      if (isFn && command && typeof command === 'object') {
+        if (
+          typeof command.title === 'string' &&
+          typeof command.command === 'string' &&
+          typeof command.task === 'function'
+        ) {
+          const task = async (ctx = getInitialState()) => {
+            try {
+              await command.task()
+            } catch (e) {
+              throw makeErr(command.title, e, ctx)
+            }
+          }
+          cmdTasks.push({
+            title: command.title,
+            command: command.command,
+            task,
+          })
+        } else {
+          throw new Error(
+            configurationError('[Function]', 'Function task should be in proper format', resolved)
           )
-        )
+        }
+      } else {
+        // If the function linter didn't return string | string[]  it won't work
+        // Do the validation here instead of `validateConfig` to skip evaluating the function multiple times
+        if (isFn && typeof command !== 'string') {
+          throw new Error(
+            configurationError(
+              '[Function]',
+              'Function task should return a string or an array of strings',
+              resolved
+            )
+          )
+        }
+        const task = resolveTaskFn({ command, cwd, files, gitDir, isFn, shell, verbose })
+        cmdTasks.push({ title: command, command, task })
       }
-
-      const task = resolveTaskFn({ command, cwd, files, gitDir, isFn, shell, verbose })
-      cmdTasks.push({ title: command, command, task })
     }
   }
 

lib/resolveTaskFn.js

@@ -108,7 +108,7 @@ const interruptExecutionOnError = (ctx, execaChildProcess) => {
  * @param {Object} ctx
  * @returns {Error}
  */
-const makeErr = (command, result, ctx) => {
+export const makeErr = (command, result, ctx) => {
   ctx.errors.add(TaskError)
 
   // https://nodejs.org/api/events.html#error-events