Fix printing recursive value or pattern

README.md

@@ -519,7 +519,7 @@ oneIsTwo(3)
 ```
 ```
 [ 3 ]
-/home/ant/projects/patroon/src/index.js:92
+/home/ant/projects/patroon/src/index.js:93
       throw error
       ^
 
@@ -534,12 +534,12 @@ Another error that occurs is when the patroon function is not used correctly.
 patroon(1)
 ```
 ```
-/home/ant/projects/patroon/src/index.js:79
+/home/ant/projects/patroon/src/index.js:80
   if (!isEven(list.length)) { throw new UnevenArgumentCountError('Patroon should have an even amount of arguments.') }
                               ^
 
 UnevenArgumentCountError: Patroon should have an even amount of arguments.
-    at patroon (/home/ant/projects/patroon/src/index.js:79:37)
+    at patroon (/home/ant/projects/patroon/src/index.js:80:37)
 ```
 
 #### PatroonError
@@ -594,10 +594,10 @@ npx nyc check-coverage
      walkable.js |     100 |      100 |     100 |     100 |                   
     -------------|---------|----------|---------|---------|-------------------
 
-  total:     16
-  passing:   16
+  total:     19
+  passing:   19
 
-  duration:  1.6s
+  duration:  1.4s
 
 ```
 

src/index.js

@@ -1,5 +1,6 @@
 const { mapLeaves, path, PathError } = require('./walkable')()
 const { isFunction, equals, T, is, tryCatch, isEven, isNil, toPairs, always } = require('./helpers')
+const { inspect } = require('util')
 
 const deprecated = (fn, message) => (...args) => {
   console.error(`[patroon] deprecated: ${message}`)
@@ -87,7 +88,7 @@ const patroon = (...list) => {
       const error = new NoMatchError('Not able to match any pattern for arguments')
       error.arguments = args
 
-      console.error(args)
+      console.error(inspect(args))
 
       throw error
     }

src/index.test.js

@@ -171,3 +171,22 @@ test('Deprecated functions', ts => {
   console.error = consoleError
   ts.end()
 })
+
+// Circular reference
+const circular = {}
+circular.a = circular
+
+test('At the moment recursive patterns throw and print', t => {
+  t.plan(1)
+  t.throws(() => patroon(circular, true)({}))
+})
+
+test('Throws and prints because path is not defined', t => {
+  t.plan(1)
+  t.throws(() => patroon({ b: _ }, true)(circular))
+})
+
+test('Does not throw when value is recursive', t => {
+  t.plan(1)
+  t.ok(patroon({ a: _ }, true)(circular))
+})

src/walkable.js

@@ -44,7 +44,7 @@ function path (pth, v, errorData) {
 
   if (!(key in v)) {
     const error = new PathError(
-      `Cannot read property '${JSON.stringify(pth)}' of ${JSON.stringify(v)}`)
+      `Cannot read path ${pth}.`)
 
     Object.assign(error, errorData)