Improved prettify when escape characters and add tests (#291)

.eslintignore

@@ -4,3 +4,4 @@ dist/**/*
 coverage/**/*
 node_modules/**/*
 webpack/**/*
+**/__fixtures__/prettify/*

app/common/__fixtures__/prettify/escaped-characters-input.json

@@ -0,0 +1 @@
+{"slash": "\\", "slashes": "\\\\", "quote": "\""}

app/common/__fixtures__/prettify/escaped-characters-output.json

@@ -0,0 +1,6 @@
+{
+  "slash": "\\",
+  "slashes": "\\\\",
+  "quote": "\""
+}
+

app/common/__fixtures__/prettify/extra-whitespace-input.json

@@ -0,0 +1,12 @@
+{
+
+  "foo":    "bar",
+  "arr": [
+    1,
+    2,
+
+    3,
+    4
+
+  ]
+}

app/common/__fixtures__/prettify/extra-whitespace-output.json

@@ -0,0 +1,9 @@
+{
+  "foo": "bar",
+  "arr": [
+    1,
+    2,
+    3,
+    4
+  ]
+}

app/common/__fixtures__/prettify/minimal-whitespace-input.json

@@ -0,0 +1 @@
+{"foo":"bar","arr":[1,2,3,4],"object":{"foo":{},"empty":[]}}

app/common/__fixtures__/prettify/minimal-whitespace-output.json

@@ -0,0 +1,13 @@
+{
+  "foo": "bar",
+  "arr": [
+    1,
+    2,
+    3,
+    4
+  ],
+  "object": {
+    "foo": {},
+    "empty": []
+  }
+}

app/common/__fixtures__/prettify/precision-input.json

@@ -0,0 +1,6 @@
+{
+  "float": 1.24815739284710478594274018450372432784024,
+  "round": 1.000000,
+  "invalid": foo,
+  "exponent": 1E5
+}

app/common/__fixtures__/prettify/precision-output.json

@@ -0,0 +1,6 @@
+{
+  "float": 1.24815739284710478594274018450372432784024,
+  "round": 1.000000,
+  "invalid": foo,
+  "exponent": 1E5
+}

app/common/__fixtures__/prettify/root-array-input.json

@@ -0,0 +1 @@
+[1,2,3]

app/common/__fixtures__/prettify/root-array-output.json

@@ -0,0 +1,6 @@
+[
+  1,
+  2,
+  3
+]
+

app/common/__fixtures__/prettify/root-string-input.json

@@ -0,0 +1 @@
+"Hello World!"

app/common/__fixtures__/prettify/root-string-output.json

@@ -0,0 +1 @@
+"Hello World!"

app/common/__fixtures__/prettify/trailing-comma-input.json

@@ -0,0 +1 @@
+{"foo": "bar", "array": [1,2,3,4,],"last": "comma",}

app/common/__fixtures__/prettify/trailing-comma-output.json

@@ -0,0 +1,10 @@
+{
+  "foo": "bar",
+  "array": [
+    1,
+    2,
+    3,
+    4,
+  ],
+  "last": "comma",
+}

app/common/__fixtures__/prettify/unquoted-strings-input.json

@@ -0,0 +1 @@
+{foo: bar, bar: [1,2,3,number?]}

app/common/__fixtures__/prettify/unquoted-strings-output.json

@@ -0,0 +1,10 @@
+{
+  foo: bar,
+  bar: [
+    1,
+    2,
+    3,
+    number?
+  ]
+}
+

app/common/__tests__/prettify.test.js

@@ -0,0 +1,23 @@
+import {prettifyJson} from '../prettify';
+import fs from 'fs';
+import path from 'path';
+
+describe('prettify()', () => {
+  const basePath = path.join(__dirname, '../__fixtures__/prettify');
+  const files = fs.readdirSync(basePath);
+  for (const file of files) {
+    if (!file.match(/-input\.json$/)) {
+      continue;
+    }
+
+    const slug = file.replace(/-input\.json$/, '');
+    const name = slug.replace(/-/g, ' ');
+
+    it(`handles ${name}`, () => {
+      const input = fs.readFileSync(path.join(basePath, `${slug}-input.json`), 'utf8').trim();
+      const output = fs.readFileSync(path.join(basePath, `${slug}-output.json`), 'utf8').trim();
+      const result = prettifyJson(input, '  ');
+      expect(result).toBe(output);
+    });
+  }
+});

app/common/prettify.js

@@ -7,7 +7,7 @@
  * @param indentChars
  * @returns {string}
  */
-export function prettifyJson (json, indentChars) {
+export function prettifyJson (json, indentChars = '\t') {
   // Convert the unicode. To correctly mimic JSON.stringify(JSON.parse(json), null, indentChars)
   // we need to convert all escaped unicode characters to proper unicode characters.
   try {
@@ -19,10 +19,11 @@ export function prettifyJson (json, indentChars) {
 
   let i = 0;
   let il = json.length;
-  let tab = (typeof indentChars !== 'undefined') ? indentChars : '    ';
+  let tab = indentChars;
   let newJson = '';
   let indentLevel = 0;
   let inString = false;
+  let isEscaped = false;
   let currentChar = null;
   let previousChar = null;
   let nextChar = null;
@@ -32,7 +33,18 @@ export function prettifyJson (json, indentChars) {
     previousChar = json.charAt(i - 1);
     nextChar = json.charAt(i + 1);
 
+    // Handle the escaped case
+    if (isEscaped) {
+      isEscaped = false;
+      newJson += currentChar;
+      continue;
+    }
+
     switch (currentChar) {
+      case '\\':
+        isEscaped = !isEscaped;
+        newJson += currentChar;
+        break;
       case '{':
         if (!inString && nextChar !== '}') {
           newJson += currentChar + '\n' + _repeatString(tab, indentLevel + 1);
@@ -87,9 +99,7 @@ export function prettifyJson (json, indentChars) {
         }
         break;
       case '"':
-        if (previousChar !== '\\') {
-          inString = !inString;
-        }
+        inString = !inString;
         newJson += currentChar;
         break;
       case '\r':
@@ -101,7 +111,8 @@ export function prettifyJson (json, indentChars) {
     }
   }
 
-  return newJson;
+  // Remove lines that only contain whitespace
+  return newJson.replace(/^\s*\n/gm, '');
 }
 
 function _repeatString (s, count) {