Add a public method to retrieve output from "terminalreporter" as a string

Hi!

What's the problem this feature will solve?

I would like to be able to easily retrieve the entire test report as a string.

I know there exists plugins like pytest-html or pytest-junitxml. However, I much prefer the default terminal output:

• it is perfectly detailed and contains all information needed
• everybody is familiar with the format of this tests report
• it can be read as "raw" in any text editor

Describe the solution you'd like

Possibly adding a method to the TerminalReporter allowing to get the generated report.

The final goal is to be able to send the complete results by email at the end of the tests for example.

Alternative Solutions

It's possible to redirect output of pytest command but that would prevent to implement pytest-email-reporter as a plugin for example.

The solution I currently use is based on the pastebin plugin which is actually part of the pytest repo: https://github.com/pytest-dev/pytest/blob/89dcfbf293802b6efacc5aea2893f9fec03787bc/src/_pytest/pastebin.py#L31-L49

As you see it requires first to access the protected _tw attribute of the "terminalreporter" plugin and then wrapping its .write() method.

It's working very well but I feel uncomfortable "hacking" pytest internals like this. An official API that would permit to access the session report during pytest_terminal_summary() or pytest_unconfigure() would be perfect.

The drawback is that it would consume more memory since the generated string has to be stored somewhere. Maybe it needs to be configurable. Another possibility is to provide a method for formatting the report, but this seems to require more work.

Additional context

Depending on what you decide, I can implement the solution and open the corresponding PR.

Start with src/_pytest/pastebin.py, especially the handling of the terminalreporter plugin and its protected _tw attribute. Read the TerminalReporter entry points used during pytest_terminal_summary() and pytest_unconfigure() to understand when output is available. Done means a documented public API can retrieve the complete terminal report for plugins without wrapping internal methods, with coverage for the relevant lifecycle hooks.