tests: make treesitter its own category

test/functional/treesitter/language_spec.lua

@@ -0,0 +1,71 @@
+local helpers = require('test.functional.helpers')(after_each)
+
+local clear = helpers.clear
+local eq = helpers.eq
+local exec_lua = helpers.exec_lua
+local pcall_err = helpers.pcall_err
+local matches = helpers.matches
+local pending_c_parser = helpers.pending_c_parser
+
+before_each(clear)
+
+describe('treesitter API', function()
+  -- error tests not requiring a parser library
+  it('handles missing language', function()
+    eq("Error executing lua: .../language.lua:0: no parser for 'borklang' language, see :help treesitter-parsers",
+       pcall_err(exec_lua, "parser = vim.treesitter.get_parser(0, 'borklang')"))
+
+    -- actual message depends on platform
+    matches("Error executing lua: Failed to load parser: uv_dlopen: .+",
+       pcall_err(exec_lua, "parser = vim.treesitter.require_language('borklang', 'borkbork.so')"))
+
+    -- Should not throw an error when silent
+    eq(false, exec_lua("return vim.treesitter.require_language('borklang', nil, true)"))
+    eq(false, exec_lua("return vim.treesitter.require_language('borklang', 'borkbork.so', true)"))
+
+    eq("Error executing lua: .../language.lua:0: no parser for 'borklang' language, see :help treesitter-parsers",
+       pcall_err(exec_lua, "parser = vim.treesitter.inspect_language('borklang')"))
+  end)
+
+  it('inspects language', function()
+    if pending_c_parser(pending) then return end
+
+    local keys, fields, symbols = unpack(exec_lua([[
+      local lang = vim.treesitter.inspect_language('c')
+      local keys, symbols = {}, {}
+      for k,_ in pairs(lang) do
+        keys[k] = true
+      end
+
+      -- symbols array can have "holes" and is thus not a valid msgpack array
+      -- but we don't care about the numbers here (checked in the parser test)
+      for _, v in pairs(lang.symbols) do
+        table.insert(symbols, v)
+      end
+      return {keys, lang.fields, symbols}
+    ]]))
+
+    eq({fields=true, symbols=true}, keys)
+
+    local fset = {}
+    for _,f in pairs(fields) do
+      eq("string", type(f))
+      fset[f] = true
+    end
+    eq(true, fset["directive"])
+    eq(true, fset["initializer"])
+
+    local has_named, has_anonymous
+    for _,s in pairs(symbols) do
+      eq("string", type(s[1]))
+      eq("boolean", type(s[2]))
+      if s[1] == "for_statement" and s[2] == true then
+        has_named = true
+      elseif s[1] == "|=" and s[2] == false then
+        has_anonymous = true
+      end
+    end
+    eq({true,true}, {has_named,has_anonymous})
+  end)
+end)
+