How can I configure the "Run" button next to the editor tabs in VS Code for Python files?

I have the following configuration in my launch.json:

<!-- language: lang-json -->

{
    "configurations": 
    [
    {
      "name": "Python: Current File",
      "type": "python",
      "request": "launch",
      "program": "${file}",
      "console": "integratedTerminal",
      "justMyCode": true,
      "cwd": "${fileDirname}",
      "env": {"PYTHONPATH": "C:/repo/python"}
    }
    ]
}

With this, I can easily run and debug the current script from the Run/Debug side panel:

All good, so far. But now I'd like to also be able to directly run the script from the Run button on the editor tabs:

Unfortunately, this does not work. It runs the file, but the configuration from above is not taken.

How can I add a configuration with PYTHONPATH etc. also for this Run button in the editor tabs?

Note that launch.json only works for debugging. The triangle button in the upper right corner of the editor interface only runs or debugs the current script file, and does not apply the configuration in launch.

If you want to debug the file outside the Run and Debug panel and use launch.json, use the shortcut key <kbd>Ctrl</kbd>+<kbd>F5</kbd> or the top menu Run-->Run Without Debugging.

As for the configuration of the play button in the upper right corner you mentioned, this has existed on GitHub, but not enough votes have been collected. If you are interested in this, you can continue to raise it and pay attention.

I'm pretty sure the Run Python File button invokes the same thing as the Python: Run Python File in Terminal command in the command palette, which- if I understand correctly- uses settings that start with python.terminal.*. The current list of those settings at the time of this writing is the following (shown with their default values):

// Activate Python Environment in the current Terminal on load of the Extension.
"python.terminal.activateEnvInCurrentTerminal": false,

// Activate Python Environment in all Terminals created.
"python.terminal.activateEnvironment": true,

// When executing a file in the terminal, whether to use execute in the file's directory, instead of the current open folder.
"python.terminal.executeInFileDir": false,

// When launching a python terminal, whether to focus the cursor on the terminal.
"python.terminal.focusAfterLaunch": false,

// Python launch arguments to use when executing a file in the terminal.
"python.terminal.launchArgs": [],

Note: docs on debugging Python can be found here: https://code.visualstudio.com/docs/python/debugging.

There is a property in python-type launch configs called "purpose", where you can put "debug-in-terminal" in the array value, which seems to make it so the launch config will apply when use the "debug in terminal" mode of the play button at the top-right of the screen.

For commandline arguments, use the python.terminal.launchArgs setting. As for PYTHONPATH, that's an environment variable, so you'll have to modify each of terminal.integrated.env.windows, terminal.integrated.env.osx, terminal.integrated.env.linux in your settings.json file (you can do it in the workspace or user settings.json file). Ex.

"terminal.integrated.env.linux": {
    "FOO": "foo",
    "BAR": "hello",
    "BAZ": "baz",
},
// repeat for OSX and Windows (unfortunately, it's repetitive)

Note also that since the Python: Run Python File in Terminal feature attempts to reuse the terminal, and that you can't (as far as I know) change a process' environment variables after it has been created, you'll need to close that terminal to get changes you make to the terminal.integrated.env.* to get "picked up" (from the terminal being recreated, and the shell process along with it).

Note: There's a related issue ticket at: Allow "Run Python File in Terminal" button to be configurable #11812.