i-am-the-slime/Diff.js

## Diff.js
"use strict"
var diff2html = require("diff2html").Diff2Html;
var unidiff = require('unidiff');
var stringify = require('json-stable-stringify');

exports.stableStringify = function(x) {
    return stringify(x);
}

exports.isJsonEqual = function(a) {
    return function(b) {
        return stringify(a) === stringify(b)
    }
}

exports.getPrettyHtml = function(filename) {
        return function(a) {
            return function(b) {
                var aa = stringify(a, {space: 4});
                var bb = stringify(b, {space: 4});
                var diff = unidiff.diffAsText(bb, aa, { aname: filename, bname: "actual"});
                return Diff2Html.getPrettyHtml(
                    diff,
                    {inputFormat: 'diff', showFiles: true, matching: 'lines', outputFormat: 'side-by-side'}
                );
            };
        };
    }

## Diff.purs
module Test.Spec.Assertions.Diff
  ( shouldHaveNoDiff
  , shouldBeGolden
  , Actual(..)
  , Expected(..)
  , GoldenFile(..)
  , (=|=)
  ) where

import Prelude
import Data.Newtype (class Newtype)
import Effect.Aff (Aff)
import Foreign (Foreign)
import Node.Encoding (Encoding(..))
import Node.FS.Aff (exists, writeTextFile)
import Test.Spec.Assertions (fail)
import Test.Spec.File (fileAsForeign, writeToTmpFile)

foreign import getPrettyHtml ∷ String -> Foreign -> Foreign -> String

foreign import isJsonEqual ∷ Foreign -> Foreign -> Boolean

foreign import stableStringify ∷ Foreign -> String

newtype Actual = Actual Foreign

derive instance ntActual ∷ Newtype Actual _
newtype Expected = Expected Foreign

derive instance ntExpected ∷ Newtype Expected _
newtype GoldenFile = GoldenFile String

derive instance ntGoldenFile ∷ Newtype GoldenFile _
infix 4 shouldHaveNoDiff as =|=

shouldBeGolden ∷ Actual -> GoldenFile -> Aff Unit
shouldBeGolden actual@(Actual content) (GoldenFile path) = do
  exist <- exists path
  if exist then do
    expected <- fileAsForeign path
    shouldHaveNoDiff' actual path (Expected expected)
  else do
    writeTextFile UTF8 path (stableStringify content)
    fail $ "Recreated " <> path

shouldHaveNoDiff' ∷ Actual -> String -> Expected -> Aff Unit
shouldHaveNoDiff' (Actual v1) expectedName (Expected v2) =
  unless (v1 `isJsonEqual` v2)
    $ do
        let
          before =
            """<!DOCTYPE html>
        <html>
          <head>
            <link rel="stylesheet"
                  type="text/css"
                  href="https://cdnjs.cloudflare.com/ajax/libs/diff2html/2.5.0/diff2html.min.css">
            <style>
            .d2h-code-side-linenumber, .d2h-code-line-prefix {
              -webkit-touch-callout: none;
              -webkit-user-select: none;
              -khtml-user-select: none;
              -moz-user-select: none;
              -ms-user-select: none;
              user-select: none;
            }
            </style>
            <title>diff2html</title>
          </head>
          <body>
            <div>
        """
        let
          after = "</div></body></html>"
        let
          diff = getPrettyHtml expectedName v1 v2
        path <- writeToTmpFile $ before <> diff <> after
        fail <<< show $ "The two JSON values are different. The diff is saved here: file://" <> path

shouldHaveNoDiff ∷ Actual -> Expected -> Aff Unit
shouldHaveNoDiff a = shouldHaveNoDiff' a "expected"
	"use strict"
	var diff2html = require("diff2html").Diff2Html;
	var unidiff = require('unidiff');
	var stringify = require('json-stable-stringify');

	exports.stableStringify = function(x) {
	return stringify(x);
	}

	exports.isJsonEqual = function(a) {
	return function(b) {
	return stringify(a) === stringify(b)
	}
	}

	exports.getPrettyHtml = function(filename) {
	return function(a) {
	return function(b) {
	var aa = stringify(a, {space: 4});
	var bb = stringify(b, {space: 4});
	var diff = unidiff.diffAsText(bb, aa, { aname: filename, bname: "actual"});
	return Diff2Html.getPrettyHtml(
	diff,
	{inputFormat: 'diff', showFiles: true, matching: 'lines', outputFormat: 'side-by-side'}
	);
	};
	};
	}
	module Test.Spec.Assertions.Diff
	( shouldHaveNoDiff
	, shouldBeGolden
	, Actual(..)
	, Expected(..)
	, GoldenFile(..)
	, (=\|=)
	) where

	import Prelude
	import Data.Newtype (class Newtype)
	import Effect.Aff (Aff)
	import Foreign (Foreign)
	import Node.Encoding (Encoding(..))
	import Node.FS.Aff (exists, writeTextFile)
	import Test.Spec.Assertions (fail)
	import Test.Spec.File (fileAsForeign, writeToTmpFile)

	foreign import getPrettyHtml ∷ String -> Foreign -> Foreign -> String

	foreign import isJsonEqual ∷ Foreign -> Foreign -> Boolean

	foreign import stableStringify ∷ Foreign -> String

	newtype Actual = Actual Foreign

	derive instance ntActual ∷ Newtype Actual _
	newtype Expected = Expected Foreign

	derive instance ntExpected ∷ Newtype Expected _
	newtype GoldenFile = GoldenFile String

	derive instance ntGoldenFile ∷ Newtype GoldenFile _
	infix 4 shouldHaveNoDiff as =\|=

	shouldBeGolden ∷ Actual -> GoldenFile -> Aff Unit
	shouldBeGolden actual@(Actual content) (GoldenFile path) = do
	exist <- exists path
	if exist then do
	expected <- fileAsForeign path
	shouldHaveNoDiff' actual path (Expected expected)
	else do
	writeTextFile UTF8 path (stableStringify content)
	fail $ "Recreated " <> path

	shouldHaveNoDiff' ∷ Actual -> String -> Expected -> Aff Unit
	shouldHaveNoDiff' (Actual v1) expectedName (Expected v2) =
	unless (v1 `isJsonEqual` v2)
	$ do
	let
	before =
	"""<!DOCTYPE html>
	<html>
	<head>
	<link rel="stylesheet"
	type="text/css"
	href="https://cdnjs.cloudflare.com/ajax/libs/diff2html/2.5.0/diff2html.min.css">
	<style>
	.d2h-code-side-linenumber, .d2h-code-line-prefix {
	-webkit-touch-callout: none;
	-webkit-user-select: none;
	-khtml-user-select: none;
	-moz-user-select: none;
	-ms-user-select: none;
	user-select: none;
	}
	</style>
	<title>diff2html</title>
	</head>
	<body>
	<div>
	"""
	let
	after = "</div></body></html>"
	let
	diff = getPrettyHtml expectedName v1 v2
	path <- writeToTmpFile $ before <> diff <> after
	fail <<< show $ "The two JSON values are different. The diff is saved here: file://" <> path

	shouldHaveNoDiff ∷ Actual -> Expected -> Aff Unit
	shouldHaveNoDiff a = shouldHaveNoDiff' a "expected"