From cac8f9bf21b84bdc8f652f39d3a6c437e21de4fe Mon Sep 17 00:00:00 2001
From: Nicklas Gummesson <nicklas@dropbox.com>
Date: Mon, 14 May 2018 15:33:42 -0700
Subject: [PATCH] Calculate overall time from actual run time

Instead of summing up the individual test suite which can be significantly larger and not accurate
---
 .../__snapshots__/buildJsonResults.test.js.snap      |  2 +-
 __tests__/buildJsonResults.test.js                   |  4 ++++
 utils/buildJsonResults.js                            | 12 +++++++++---
 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/__tests__/__snapshots__/buildJsonResults.test.js.snap b/__tests__/__snapshots__/buildJsonResults.test.js.snap
index f5dcba4..5e8a628 100644
--- a/__tests__/__snapshots__/buildJsonResults.test.js.snap
+++ b/__tests__/__snapshots__/buildJsonResults.test.js.snap
@@ -8,7 +8,7 @@ Object {
         "failures": 0,
         "name": "jest tests",
         "tests": 2,
-        "time": 0.236,
+        "time": 1.234,
       },
     },
     Object {
diff --git a/__tests__/buildJsonResults.test.js b/__tests__/buildJsonResults.test.js
index 0c3985a..6cb99b7 100644
--- a/__tests__/buildJsonResults.test.js
+++ b/__tests__/buildJsonResults.test.js
@@ -102,6 +102,10 @@ describe('buildJsonResults', () => {
   it('should support displayName template var for jest multi-project', () => {
     const multiProjectNoFailingTestsReport = require('../__mocks__/multi-project-no-failing-tests.json');
 
+    // Mock Date.now() to return a fixed later value
+    const startDate = new Date(multiProjectNoFailingTestsReport.startTime);
+    spyOn(Date, 'now').and.returnValue(startDate.getTime() + 1234);
+
     const jsonResults = buildJsonResults(multiProjectNoFailingTestsReport, '',
     Object.assign({}, constants.DEFAULT_OPTIONS, {
       suiteNameTemplate: "{displayName}-foo",
diff --git a/utils/buildJsonResults.js b/utils/buildJsonResults.js
index 3b54169..414d2c1 100644
--- a/utils/buildJsonResults.js
+++ b/utils/buildJsonResults.js
@@ -13,6 +13,10 @@ const replaceVars = function (str, replacementMap) {
   return str;
 };
 
+const executionTime = function (startTime, endTime) {
+  return (endTime - startTime) / 1000;
+}
+
 module.exports = function (report, appDirectory, options) {
   // Generate a single XML file for all jest tests
   let jsonResults = {
@@ -22,7 +26,10 @@ module.exports = function (report, appDirectory, options) {
           'name': options.suiteName,
           'tests': 0,
           'failures': 0,
-          'time': 0
+          // Overall execution time:
+          // Since tests are typically executed in parallel this time can be significantly smaller
+          // than the sum of the individual test suites
+          'time': executionTime(report.startTime, Date.now())
         }
       }
     ]
@@ -59,7 +66,7 @@ module.exports = function (report, appDirectory, options) {
 
     // Add <testsuite /> properties
     const suiteNumTests = suite.numFailingTests + suite.numPassingTests + suite.numPendingTests;
-    const suiteExecutionTime = (suite.perfStats.end - suite.perfStats.start) / 1000;
+    const suiteExecutionTime = executionTime(suite.perfStats.start, suite.perfStats.end);
 
     let testSuite = {
       'testsuite': [{
@@ -78,7 +85,6 @@ module.exports = function (report, appDirectory, options) {
     // Update top level testsuites properties
     jsonResults.testsuites[0]._attr.failures += suite.numFailingTests;
     jsonResults.testsuites[0]._attr.tests += suiteNumTests;
-    jsonResults.testsuites[0]._attr.time += suiteExecutionTime;
 
     // Iterate through test cases
     suite.testResults.forEach((tc) => {