Improve tests

package.json

@@ -36,7 +36,8 @@
     "ava": "^1.4.1",
     "gulp": "^4.0.2",
     "gulp-shared-tasks": "^0.27.81",
-    "husky": "^2.3.0"
+    "husky": "^2.3.0",
+    "pretty-format": "^24.8.0"
   },
   "engines": {
     "node": ">=8.12.0"

test/helpers/error.js

@@ -0,0 +1,17 @@
+// Make sure exceptions are snapshot as well
+export const stringifyErrors = function(func) {
+  return addErrorHandler(func, String)
+}
+
+// Wrap a function with a error handler
+const addErrorHandler = function(func, errorHandler) {
+  return errorHandledFunc.bind(null, func, errorHandler)
+}
+
+const errorHandledFunc = function(func, errorHandler, ...args) {
+  try {
+    return func(...args)
+  } catch (error) {
+    return errorHandler(error, ...args)
+  }
+}

test/main.js

@@ -1,7 +1,40 @@
 import test from 'ava'
+import prettyFormat from 'pretty-format'
 
 import fastCartesian from '../src/main.js'
 
-test('Dummy test', t => {
-  t.is(typeof fastCartesian, 'function')
+import { stringifyErrors } from './helpers/error.js'
+
+const eFastCartesian = stringifyErrors(fastCartesian)
+
+const generator = function*() {
+  yield 0
+  yield 1
+}
+
+;[
+  [],
+  [[]],
+  [[], []],
+  [undefined],
+  [null],
+  [[], true],
+  [[0]],
+  [[0], [1]],
+  [[0, 1]],
+  [[0, 1], [2]],
+  [[0, 1], [2, 3]],
+  // eslint-disable-next-line no-magic-numbers
+  [[0, 1, 2], [3, 4]],
+  [[[0]]],
+  [[0, undefined, 1]],
+  ['abc'],
+  [new Map([[{}, 0], [{}, 1]])],
+  [new Set([0, 1])],
+  [generator()],
+].forEach(args => {
+  const title = prettyFormat(args, { min: true })
+  test(title, t => {
+    t.snapshot(eFastCartesian(...args))
+  })
 })

test/snapshots/main.js.md

@@ -0,0 +1,233 @@
+# Snapshot report for `test/main.js`
+
+The actual snapshot is saved in `main.js.snap`.
+
+Generated by [AVA](https://ava.li).
+
+## ["abc"]
+
+> Snapshot 1
+
+    [
+      [
+        'a',
+      ],
+      [
+        'b',
+      ],
+      [
+        'c',
+      ],
+    ]
+
+## [Map {{} => 0, {} => 1}]
+
+> Snapshot 1
+
+    [
+      [
+        [
+          {},
+          0,
+        ],
+      ],
+      [
+        [
+          {},
+          1,
+        ],
+      ],
+    ]
+
+## [Set {0, 1}]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+      ],
+      [
+        1,
+      ],
+    ]
+
+## [[0, 1, 2], [3, 4]]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+        3,
+      ],
+      [
+        0,
+        4,
+      ],
+      [
+        1,
+        3,
+      ],
+      [
+        1,
+        4,
+      ],
+      [
+        2,
+        3,
+      ],
+      [
+        2,
+        4,
+      ],
+    ]
+
+## [[0, 1], [2, 3]]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+        2,
+      ],
+      [
+        0,
+        3,
+      ],
+      [
+        1,
+        2,
+      ],
+      [
+        1,
+        3,
+      ],
+    ]
+
+## [[0, 1], [2]]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+        2,
+      ],
+      [
+        1,
+        2,
+      ],
+    ]
+
+## [[0, 1]]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+      ],
+      [
+        1,
+      ],
+    ]
+
+## [[0, undefined, 1]]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+      ],
+      [
+        undefined,
+      ],
+      [
+        1,
+      ],
+    ]
+
+## [[0], [1]]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+        1,
+      ],
+    ]
+
+## [[0]]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+      ],
+    ]
+
+## [[[0]]]
+
+> Snapshot 1
+
+    [
+      [
+        [
+          0,
+        ],
+      ],
+    ]
+
+## [[], []]
+
+> Snapshot 1
+
+    []
+
+## [[], true]
+
+> Snapshot 1
+
+    'TypeError: Argument must be iterable: true'
+
+## [[]]
+
+> Snapshot 1
+
+    []
+
+## []
+
+> Snapshot 1
+
+    []
+
+## [null]
+
+> Snapshot 1
+
+    'TypeError: Argument must be iterable: null'
+
+## [undefined]
+
+> Snapshot 1
+
+    'TypeError: Argument must be iterable: undefined'
+
+## [{}]
+
+> Snapshot 1
+
+    [
+      [
+        0,
+      ],
+      [
+        1,
+      ],
+    ]