Use Jest for tests (#72)

* Use Jest for tests

* Fix return type for typescript

* Refactoring: use more functions

* eslint max len 120

* Add function for parsing page

* Add tests with jest

* Move test, add new test

* Add function to jest ignored files to run coverage

* Update version

.eslintrc.json

@@ -3,15 +3,15 @@
       "commonjs": true,
       "es2021": true,
       "node": true,
-      "mocha": true
+      "jest": true
     },
     "extends": "google",
     "parserOptions": {
       "ecmaVersion": 12
     },
     "rules": {
       "max-len": [
-        "error", 100
+        "error", 120
       ],
       "object-curly-spacing": [
         "error", "always"

functions.js

@@ -14,6 +14,17 @@ function mapResponse(array) {
   }));
 }
 
+/**
+ * Get JSON response from Investing APIs
+ * @param {*} page puppeteer page
+ * @return {Object} JSON response from Investing
+ */
+async function getJsonContent(page) {
+  const content = await page.evaluate(() => document.querySelector('body').textContent);
+  return JSON.parse(content);
+}
+
 module.exports = {
   mapResponse,
+  getJsonContent,
 };

index.d.ts

@@ -4,5 +4,12 @@ declare module "investing-com-api" {
     period?: 'P1D' | 'P1W' | 'P1M' | 'P3M' | 'P6M' | 'P1Y' | 'P5Y' | 'MAX',
     interval?: 'PT1M' | 'PT5M' | 'PT15M' | 'PT30M' | 'PT1H' | 'PT5H' | 'P1D' | 'P1W' | 'P1M',
     pointscount?: 60 | 70 | 120
-  ): { date: number, value: number }[];
+  ): {
+    date: number,
+    value: number,
+    price_open: number,
+    price_high: number,
+    price_low: number,
+    price_close: number,
+  }[];
 }

index.js

@@ -1,6 +1,32 @@
 const puppeteer = require('puppeteer');
 const { mapping } = require('./mapping');
-const { mapResponse } = require('./functions');
+const { getJsonContent, mapResponse } = require('./functions');
+
+const validPeriod = ['P1D', 'P1W', 'P1M', 'P3M', 'P6M', 'P1Y', 'P5Y', 'MAX'];
+const validInterval = ['PT1M', 'PT5M', 'PT15M', 'PT30M', 'PT1H', 'PT5H', 'P1D', 'P1W', 'P1M'];
+const validPointscount = [60, 70, 120];
+
+/**
+ * Check if params are valid
+ * @param {String} input input
+ * @param {String} period period
+ * @param {String} interval interval
+ * @param {Number} pointscount pointscount
+ */
+function checkParams(input, period, interval, pointscount) {
+  if (!input) {
+    throw Error('Parameter input is required');
+  }
+  if (!validPeriod.includes(period)) {
+    throw Error('Invalid period parameter. Valid values are: P1D, P1W, P1M, P3M, P6M, P1Y, P5Y, MAX');
+  }
+  if (!validInterval.includes(interval)) {
+    throw Error('Invalid interval parameter. Valid values are: PT1M, PT5M, PT15M, PT30M, PT1H, PT5H, P1D, P1W, P1M');
+  }
+  if (!validPointscount.includes(pointscount)) {
+    throw Error('Invalid pointscount parameter. Valid values are: 60, 70, 120');
+  }
+}
 
 /**
  * Call Investing
@@ -19,9 +45,8 @@ async function callInvesting(pairId, period, interval, pointscount) {
   await page.setUserAgent('Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36');
   // eslint-disable-next-line max-len
   await page.goto(`https://api.investing.com/api/financialdata/${pairId}/historical/chart?period=${period}&interval=${interval}&pointscount=${pointscount}`);
-  const content = await page.evaluate(() => document.querySelector('body').textContent);
+  const jsonContent = await getJsonContent(page);
   await browser.close();
-  const jsonContent = JSON.parse(content);
   return jsonContent;
 }
 
@@ -38,9 +63,7 @@ async function callInvesting(pairId, period, interval, pointscount) {
  */
 async function investing(input, period = 'P1M', interval = 'P1D', pointscount = 120) {
   try {
-    if (!input) {
-      throw Error('Parameter input is required');
-    }
+    checkParams(input, period, interval, pointscount);
     const endpoint = mapping[input];
     if (!endpoint) {
       throw Error(`No mapping found for ${input}, check mapping.js`);