Code coverage getting dropped when we combine code coverage from karma unit test case and from cypress integration test case

[rk011219]

Logs and screenshots
I have angular 14 project where I am using karma framework for unit testing and cypress for integration test. I have separate code coverage for karma unit test and cypress integration test and I have combined both code coverage json files but code coverage got dropped after merging. I think code coverage is taking delta of them.

Karma Unit test case coverage:-

Cypress Integration code coverage:-

Combined Code coverage:-

If you see above reports, I am expecting combine report should show 100 % code coverage for components/sym-ui-sedr-actions because I have covered the component in integration test but it was showing delta. Is there any solution?

Versions

Cypress 10.8.0
"cypress-parallel": "0.9.1",
"@cypress/code-coverage": "3.10.0",
Angular 12.1.3
os : windows 10, linux
Node v12.22.3
npm v6.14.13
application instrumented using istambul and followed below lnk
https://lukas-klement.medium.com/implementing-code-coverage-with-angular-and-cypress-6ed08ed7e617

window.coverage : yes

Is there .nyc_output folder? Is there .nyc_output/out.json file.
-yes
Do you have any custom NYC settings in package.json (nyc object) or in other [NYC config files]
yes
{
"extends": "@istanbuljs/nyc-config-typescript",
"all": true,
"excludeAfterRemap": true,
"reporter": ["html"],
"exclude": [
"./coverage/",
"cypress/",
"./dist/",
"/.spec.ts",
"/projects//test.ts",
"/projects//.js",
"./.js",
"./.config.ts",
"/projects//*.html",
"./src/**"
]
}
Do you run Cypress tests in a Docker container?
NO

Describe the bug
If you see above reports, I am expecting combine report should show 100 % code coverage for components/sym-ui-sedr-actions because I have covered the component in integration test but it was showing delta. Is there any solution?

FYI I am using Istanbul for instrumenting code for karma as well as for cypress

Example
.nycrc.json
{
"extends": "@istanbuljs/nyc-config-typescript",
"all": true,
"excludeAfterRemap": true,
"exclude": [
"./coverage/",
"cypress/",
"./dist/",
"/.spec.ts",
"/projects//test.ts",
"/projects//.js",
"./.js",
"./.config.ts",
"/projects//*.html",
"./src/**"
]
}

Krama.config.js
module.exports = function (config) {
config.set({
basePath: '',
frameworks: ['jasmine', '@angular-devkit/build-angular'],
plugins: [
require('karma-jasmine'),
require('karma-chrome-launcher'),
require('karma-firefox-launcher'),
require('karma-jasmine-html-reporter'),
require('karma-json-reporter'),
require('karma-coverage'),
require('karma-spec-reporter'),
require('@angular-devkit/build-angular/plugins/karma'),
],
client: {
jasmine: {
random: false,
seed: '4321',
oneFailurePerSpec: true,
failFast: true,
timeoutInterval: 30 * 1000,
},
clearContext: false, // leave Jasmine Spec Runner output visible in browser
},
jasmineHtmlReporter: {
suppressAll: true, // removes the duplicated traces
},
coverageReporter: {
check: {
emitWarning: false,
global: {
statements: 85.42,
branches: 70,
functions: 84.37,
lines: 81.76,
excludes: ['src/**/*.js'],
},
},
dir: require('path').join(__dirname, '../../../coverage/sym-ui/sedr'),
instrumenterOptions: {
istanbul: { noCompact: true },
},
reporters: [{ type: 'html' },{ type: 'json' }, { type: 'text-summary' }],
subdir: '.',
watermarks: {
statements: [60, 85],
functions: [60, 85],
branches: [60, 85],
lines: [60, 85],
},
},
reporters: ['spec', 'progress', 'kjhtml', 'json'],
port: 0,
colors: true,
logLevel: config.LOG_INFO,
autoWatch: true,
// start these browsers
// available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
// Start these browsers, currently available:
// - ChromeHeadlessNoSandbox
// - Chrome
// - ChromeCanary
// - Firefox
// - Opera
// - Safari (only Mac)
// - IE (only Windows)
browsers: ['ChromeHeadlessNoSandbox'],
customLaunchers: {
ChromeHeadlessNoSandbox: {
base: 'ChromeHeadless',
flags: [
'--disable-web-security',
'--disable-gpu',
'--no-sandbox'
]
},
},
captureTimeout: 100 * 1000,
reportSlowerThan: 5000,
singleRun: false,
restartOnFileChange: true,
browserDisconnectTimeout: 100 * 1000,
browserDisconnectTolerance: 8,
browserNoActivityTimeout: 100 * 1000,
});
};

[Scott-Fischer]

I'm seeing this as well with combined reports from Jest and Cypress

[maciek-ibm]

When running only Cypress the coverage i.e. in statements is 86.29% but after merging coverage from Cypress & Jest it drops to 80.17%. Does anyone here know how to fix this?