chore: POC plenary test

[alex-courtis]

Plenary test is used by
telescope
lualine
packer

It allows static mocking of nvim functions.

[gegoune]

I can't recall where and when it was but I have seen projects moving away from plenary tests. Might be worth exploring what top plugins in the ecosystem use/do.

[GCrispino]

I don't have a lot of experience in the neovim development space, so I don't think I can weigh in too much here, sorry :/ .

I guess my only question would be setup wise. I checked the branch out on MacOS and ran the script in ./scripts/test.sh, but got an error - I believe I need to install plenary or something like that?

[GCrispino]

Is this intended?

[alex-courtis]

Whoops... didn't need that one...

[GCrispino]

Should we add a command in Makefile (e.g. make test) that runs this?

[alex-courtis]

Yup. It can then run in CI.

[GCrispino]

I can't recall where and when it was but I have seen projects moving away from plenary tests. Might be worth exploring what top plugins in the ecosystem use/do.

I know very little about this but I watched this video on the subject, which uses plenary and mentions mini.test.

[alex-courtis]

I guess my only question would be setup wise. I checked the branch out on MacOS and ran the script in ./scripts/test.sh, but got an error - I believe I need to install plenary or something like that?

Whoops... forgot to add that step - check out plenary at ./plenary.nvim

Early days; many thanks for taking a look!

[alex-courtis]

I know very little about this but I watched this video on the subject, which uses plenary and mentions mini.test.

The mini plugins are rather good, looks promising. I have homework to do.

[alex-courtis]

Tidied and added missing bits.

It looks like plenary is a subset of busted, which isn't well liked any more.

Let's see how mini goes...

[alex-courtis]

I gave mini.test a go:

• optional busted (plenary) compatibility
• nice style of laying out tests via sets
• high level of control over child vim process
• all the mini plugins have very comprehensive tests

Thoughts:

• sets are nice, but way too many strings; could probably use table keys directly
• asserts are pretty basic
• no plugins but mini uses it

Dealbreaker:

• doesn't provide mocks/stubs https://github.com/echasnovski/mini.test/blob/main/doc/mini-test.txt#L37

My Conclusion:

• Plenary works nicely

Same utils test in mini; didn't setup the harnesses, which are very close to plenary anyway.

local utils = require("nvim-tree.utils")

local new_set = MiniTest.new_set
local eq = MiniTest.expect.equality

-- Create (but not start) child Neovim object
local child = MiniTest.new_child_neovim()

local T = new_set({
  hooks = {
    post_once = child.stop,
  },
})

T["utils.path_add_trailing()"] = new_set()

T["utils.path_add_trailing()"]["trailing added"] = function()
  eq("foo/", utils.path_add_trailing("foo"))
end

T["utils.path_add_trailing()"]["trailing already present"] = function()
  eq("foo/", utils.path_add_trailing("foo/"))
end

T["utils.canonical_path()"] = new_set()

T["utils.canonical_path()"]["not windows"] = function()
  eq("c:\\foo\\bar", utils.canonical_path("c:\\foo\\bar"))
end

T["utils.canonical_path()"]["is windows"] = function()
  -- missing the ability to mock/stub
  -- https://github.com/echasnovski/mini.test/blob/main/doc/mini-test.txt#L37

  -- vim.fn.has.on_call_with("win32unix").returns(1)
  eq("c:\\foo\\bar", utils.canonical_path("C:\\foo\\bar"))
end

return T