feat(guard): throw an error if info or error are invalid

README.md

@@ -74,6 +74,9 @@ doMyStuff()
   )
 ```
 
+If `info` argument is missing a description or a solution, an error will be
+thrown.
+
 ### Small print
 
 Support: if you find any problems with this module, email / tweet /

package.json

@@ -49,7 +49,7 @@
   },
   "scripts": {
     "ban": "ban",
-    "deps": "deps-ok && dependency-check --no-dev .",
+    "deps": "deps-ok && dependency-check --no-dev --no-default-entries --entry src/index.js .",
     "issues": "git-issues",
     "license": "license-checker --production --onlyunknown --csv",
     "lint": "standard --verbose --fix src/*.js",

src/index-spec.js

@@ -44,4 +44,22 @@ describe('formErrorText', () => {
         .then(normalizeVersion)
     )
   )
+
+  describe('throws an error if', () => {
+    it('error is missing', () => {
+      la(is.raises(() => formErrorText(info)()))
+    })
+
+    it('error is not an exception', () => {
+      la(is.raises(() => formErrorText(info)('a problem')))
+    })
+
+    it('info is missing description', () => {
+      la(is.raises(() => formErrorText({solution: 'do something'})))
+    })
+
+    it('info is missing solution', () => {
+      la(is.raises(() => formErrorText({description: 'hmm'})))
+    })
+  })
 })

src/index.js

@@ -3,6 +3,8 @@
 const { stripIndents } = require('common-tags')
 const { merge } = require('ramda')
 const {getOsVersion, getPlatformInfo} = require('./get-os-info')
+const la = require('lazy-ass')
+const is = require('check-more-types')
 
 function addPlatformInformation (info) {
   return getPlatformInfo()
@@ -20,8 +22,18 @@ const utils = {
   getPlatformInfo
 }
 
+const isInfo = is.schema({
+  description: is.unemptyString,
+  solution: is.unemptyString,
+  printStack: is.maybe.bool
+})
+
 function formErrorText (info) {
+  la(isInfo(info), 'invalid info object', info)
+
   return function onError (error) {
+    la(is.error(error), 'expected error object', error)
+
     const hr = '----------'
     return formError(info, error)
     .then((extended) => stripIndents`