Breakpoints not working (with pytest-cov)

[mfussenegger]

Breakpoints not working (with pytest-cov)

[mfussenegger]

Looks like this is a pytest-cov / debugpy limitation. See microsoft/debugpy#863 (comment)

[jeanlucthumm]

The debugger works when I'm inside a non-test, main() function, set a breakpoint, and do lua require'dap'.continue(), so maybe there's something wrong with pytest setups specifically?

[philkoch]

I'm having a similar issue. Configured nvim-dap-python with examples from the docs

local mason_path = vim.fn.glob(vim.fn.stdpath "data" .. "/mason/")
require("dap-python").setup(mason_path .. "packages/debugpy/venv/bin/python")
require("dap-python").test_runner = "pytest"
-- mappings
lvim.builtin.which_key.mappings["dm"] = { "<cmd>lua require('dap-python').test_method()<cr>", "Test Method" }
lvim.builtin.which_key.mappings["df"] = { "<cmd>lua require('dap-python').test_class()<cr>", "Test Class" }

When invoking the test_method-action in a pytest-unittest file, the debugger starts as expected, but does not stop at breakpoints. Same as for the others, the debugger and breakpoints work fine when used in "normal" python modules.

[mfussenegger]

A minimal example with reproduction steps would be good.

Using a simple:

def inc(x):
    return x + 1

def test_answer():
    assert inc(3) == 5

And running :lua require('dap-python').test_method() with the cursor in test_answer, test_runner set to pytest, and a breakpoint in the inc body works fine for me.

[philkoch]

Sorry for the late reply, I didn't find time to test it earlier.
I found out what broke it for me. I'm using a poetry environment in which all dev-tools are configured via the pyproject.toml. PyTest is also configured in there:

[tool.pytest.ini_options]
addopts = "--cov" # <-- no stopping at breakpoints with --cov
testpaths = ["tests"]

When the --cov is added nvim-dap-python does not stop at breakpoints, when I remove it it works fine.