[Feature] Combine sharding with html reporter

[bamanczak]

Currently there is no way to combine test results into one html report, while using sharding on multiple machines. (v1.17.0-rc1)

I end up with multiple reports which makes it harder for sharing with others in case of failures.

It would be nice to be able to combine multiple executions into 1 report.

I believe anyone who wants to scale tests horizontally might benefit from such feature

[JoelEinbinder]

Sounds reasonable to me! What kind of api would you like to combine the reports together?

[bamanczak]

I personally have no preferences for how to merge the reports together. Whatever I can do on CI in a fast way.

[MindaugasMateika]

Since I'm currently using https://plugins.jenkins.io/allure-jenkins-plugin/ to merge multiple Allure reports and it is as simple as 👇 then I'd favor a similar approach to HTML reporter but any other out-of-the-box no-brainer solution would work as well.

            script {
                allure([
                        commandline      : 'allure-2.x',
                        includeProperties: false,
                        jdk              : '',
                        results          : [
                                [path: 'allure-results1'],
                                [path: 'allure-results2']
                        ]
                ])

[liamdebeasi]

This feature would be great to have. We are looking to migrate our E2E testing solution to Playwright. We have a component library where each test runs several variations of a particular test to check for visual regressions. Some of the variants we have are:

1. LTR vs RTL modes
2. Desktop vs mobile viewports
3. Different themes for the components

Right now the results for these tests can get split up across multiple shards. It would be great to have a single result where we can see all of the test results.