Validate input

src/exec.js

@@ -2,6 +2,7 @@ import isCi from 'is-ci'
 import execa from 'execa'
 import PluginError from 'plugin-error'
 
+import { validateInput } from './input.js'
 import { parseOpts } from './options.js'
 import { printEcho } from './echo.js'
 
@@ -14,6 +15,7 @@ import { printEcho } from './echo.js'
 // with whitespaces escaping. Also escaping is shell-specific, e.g. on Windows
 // `cmd.exe` only use double quotes not single quotes.
 export const exec = function(input, opts) {
+  validateInput({ input })
   const optsB = parseOpts({ opts, defaultOpts })
   return execCommand(input, optsB)
 }

src/input.js

@@ -0,0 +1,10 @@
+// Validate main command and arguments
+export const validateInput = function({ input }) {
+  if (!isValidInput({ input })) {
+    throw new Error('The command must be a non-empty string')
+  }
+}
+
+export const isValidInput = function({ input }) {
+  return typeof input === 'string' && input.trim() !== ''
+}

src/options.js

@@ -2,7 +2,7 @@ import { validate } from 'jest-validate'
 
 import { pickBy } from './utils.js'
 
-// Parse main arguments and options
+// Parse options
 // TODO: validate options (including that `input` is a string)
 export const parseOpts = function({ opts = {}, defaultOpts, forcedOpts = {} }) {
   const optsA = pickBy(opts, value => value !== undefined)

src/stream.js

@@ -2,6 +2,7 @@ import { callbackify } from 'util'
 
 import through from 'through2-concurrent'
 
+import { isValidInput } from './input.js'
 import { parseOpts } from './options.js'
 import { execCommand } from './exec.js'
 
@@ -48,7 +49,7 @@ const execVinyl = callbackify(cExecVinyl)
 const fireCommand = function({ input, opts }) {
   // Returning `undefined` or invalid command skips it silently.
   // `file.exec` array will be pushed with `undefined`.
-  if (typeof input !== 'string' || input.trim() === '') {
+  if (!isValidInput({ input })) {
     return
   }
 

src/task.js

@@ -1,11 +1,13 @@
 import isCi from 'is-ci'
 import renameFn from 'rename-fn'
 
+import { validateInput } from './input.js'
 import { parseOpts } from './options.js'
 import { execCommand } from './exec.js'
 
 // Create a Gulp task
 export const task = function(input, opts) {
+  validateInput({ input })
   const optsA = parseOpts({ opts, defaultOpts, forcedOpts })
 
   const gulpTask = execCommand.bind(null, input, optsA)