1 files changed, 54 insertions, 0 deletions
diff --git a/test/functional/lua/help_spec.lua b/test/functional/lua/help_spec.lua
new file mode 100644
index 0000000000..266f261ab9
--- /dev/null
+++ b/test/functional/lua/help_spec.lua
@@ -0,0 +1,54 @@
+-- Tests for gen_help_html.lua. Validates :help tags/links and HTML doc generation.
+--
+-- TODO: extract parts of gen_help_html.lua into Nvim stdlib?
+
+local helpers = require('test.functional.helpers')(after_each)
+local clear = helpers.clear
+local exec_lua = helpers.exec_lua
+local eq = helpers.eq
+local ok = helpers.ok
+
+describe(':help docs', function()
+  before_each(clear)
+  it('validate', function()
+    -- If this test fails, try these steps (in order):
+    -- 1. Try to fix/cleanup the :help docs, especially Nvim-owned :help docs.
+    -- 2. Try to fix the parser: https://github.com/vigoux/tree-sitter-vimdoc
+    -- 3. File a parser bug, and adjust the tolerance of this test in the meantime.
+
+    local rv = exec_lua([[return require('scripts.gen_help_html').validate('./build/runtime/doc')]])
+    -- Check that parse errors did not increase wildly.
+    -- TODO: yes, there are currently 24k+ parser errors.
+    --       WIP: https://github.com/vigoux/tree-sitter-vimdoc/pull/16
+    ok(rv.err_count < 24000, '<24000', rv.err_count)
+    -- TODO: should be eq(0, …)
+    ok(exec_lua('return vim.tbl_count(...)', rv.invalid_tags) < 538, '<538',
+      exec_lua('return vim.inspect(...)', rv.invalid_tags))
+  end)
+
+  it('gen_help_html.lua generates HTML', function()
+    -- Test:
+    -- 1. Check that parse errors did not increase wildly. Because we explicitly test only a few
+    --    :help files, we can be more precise about the tolerances here.
+    -- 2. exercise gen_help_html.lua, check that it actually works.
+    -- 3. check that its tree-sitter-vimdoc dependency is working.
+
+    local tmpdir = exec_lua('return vim.fs.dirname(vim.fn.tempname())')
+    -- Because gen() is slow (1 min), this test is limited to a few files.
+    local rv = exec_lua([[
+      local to_dir = ...
+      return require('scripts.gen_help_html').gen(
+        './build/runtime/doc',
+        to_dir,
+        { 'pi_health.txt', 'help.txt', 'index.txt', 'nvim.txt', }
+      )
+      ]],
+      tmpdir
+    )
+    eq(4, #rv.helpfiles)
+    ok(rv.err_count < 700, '<700', rv.err_count)
+    -- TODO: should be eq(0, …)
+    ok(exec_lua('return vim.tbl_count(...)', rv.invalid_tags) <= 32, '<=32',
+      exec_lua('return vim.inspect(...)', rv.invalid_tags))
+  end)
+end)