test: add compiler tests

lua/github-theme/_test/util.lua

@@ -1,4 +1,4 @@
-local M = {}
+local M = { unique_hlgroup = '____0' }
 local api = vim.api
 
 function M.await_VimEnter()

test/github-theme/config/compiler_spec.lua

@@ -0,0 +1,29 @@
+local assert = require('luassert')
+local t_util = require('github-theme._test.util')
+local uniqgrp = t_util.unique_hlgroup
+
+if vim.fn.has('nvim-0.9.0') == 0 or vim.fn.has('nvim-0.9.0') == false then
+  return
+end
+
+describe('compiler', function()
+  before_each(function()
+    require('github-theme.util.reload')(true)
+  end)
+
+  it('should consider previously-set overrides (1)', function()
+    local same_opts = {}
+    require('github-theme').setup(same_opts)
+    require('github-theme.override').groups = { all = { Normal = { link = uniqgrp } } }
+    require('github-theme').setup(same_opts)
+    vim.cmd.colorscheme({ args = { 'github_dark_dimmed' } })
+    assert.same({ link = uniqgrp }, t_util.get_hl('Normal', true))
+  end)
+
+  it('should consider previously-set overrides (2)', function()
+    require('github-theme').setup({})
+    require('github-theme.override').groups = { all = { Normal = { link = uniqgrp } } }
+    vim.cmd.colorscheme({ args = { 'github_dark_dimmed' } })
+    assert.same({ link = uniqgrp }, t_util.get_hl('Normal', true))
+  end)
+end)

test/minimal_init.vim

@@ -3,6 +3,6 @@ lua <<
     vim.loader.disable()
   end
 .
-set rtp+=.
-set rtp+=./test/plenary
+set rtp^=.
+set rtp^=./test/plenary
 runtime! plugin/plenary.vim