Merge remote-tracking branch 'upstream/master' into libcallnr

1 files changed, 1235 insertions, 0 deletions

diff --git a/test/functional/lua/vim_spec.lua b/test/functional/lua/vim_spec.lua
new file mode 100644
index 0000000000..9b2697b3c2
--- /dev/null
+++ b/test/functional/lua/vim_spec.lua
@@ -0,0 +1,1235 @@
+-- Test suite for testing interactions with API bindings
+local helpers = require('test.functional.helpers')(after_each)
+local Screen = require('test.functional.ui.screen')
+
+local funcs = helpers.funcs
+local meths = helpers.meths
+local command = helpers.command
+local clear = helpers.clear
+local eq = helpers.eq
+local ok = helpers.ok
+local eval = helpers.eval
+local feed = helpers.feed
+local pcall_err = helpers.pcall_err
+local exec_lua = helpers.exec_lua
+local matches = helpers.matches
+local source = helpers.source
+local NIL = helpers.NIL
+local retry = helpers.retry
+
+before_each(clear)
+
+describe('lua stdlib', function()
+  -- İ: `tolower("İ")` is `i` which has length 1 while `İ` itself has
+  --    length 2 (in bytes).
+  -- Ⱥ: `tolower("Ⱥ")` is `ⱥ` which has length 2 while `Ⱥ` itself has
+  --    length 3 (in bytes).
+  --
+  -- Note: 'i' !=? 'İ' and 'ⱥ' !=? 'Ⱥ' on some systems.
+  -- Note: Built-in Nvim comparison (on systems lacking `strcasecmp`) works
+  --       only on ASCII characters.
+  it('vim.stricmp', function()
+    eq(0, funcs.luaeval('vim.stricmp("a", "A")'))
+    eq(0, funcs.luaeval('vim.stricmp("A", "a")'))
+    eq(0, funcs.luaeval('vim.stricmp("a", "a")'))
+    eq(0, funcs.luaeval('vim.stricmp("A", "A")'))
+
+    eq(0, funcs.luaeval('vim.stricmp("", "")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0", "\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0\\0", "\\0\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0\\0\\0", "\\0\\0\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0\\0\\0A", "\\0\\0\\0a")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0\\0\\0a", "\\0\\0\\0A")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0\\0\\0a", "\\0\\0\\0a")'))
+
+    eq(0, funcs.luaeval('vim.stricmp("a\\0", "A\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("A\\0", "a\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("a\\0", "a\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("A\\0", "A\\0")'))
+
+    eq(0, funcs.luaeval('vim.stricmp("\\0a", "\\0A")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0A", "\\0a")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0a", "\\0a")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0A", "\\0A")'))
+
+    eq(0, funcs.luaeval('vim.stricmp("\\0a\\0", "\\0A\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0A\\0", "\\0a\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0a\\0", "\\0a\\0")'))
+    eq(0, funcs.luaeval('vim.stricmp("\\0A\\0", "\\0A\\0")'))
+
+    eq(-1, funcs.luaeval('vim.stricmp("a", "B")'))
+    eq(-1, funcs.luaeval('vim.stricmp("A", "b")'))
+    eq(-1, funcs.luaeval('vim.stricmp("a", "b")'))
+    eq(-1, funcs.luaeval('vim.stricmp("A", "B")'))
+
+    eq(-1, funcs.luaeval('vim.stricmp("", "\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0", "\\0\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0\\0", "\\0\\0\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0\\0\\0A", "\\0\\0\\0b")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0\\0\\0a", "\\0\\0\\0B")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0\\0\\0a", "\\0\\0\\0b")'))
+
+    eq(-1, funcs.luaeval('vim.stricmp("a\\0", "B\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("A\\0", "b\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("a\\0", "b\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("A\\0", "B\\0")'))
+
+    eq(-1, funcs.luaeval('vim.stricmp("\\0a", "\\0B")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0A", "\\0b")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0a", "\\0b")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0A", "\\0B")'))
+
+    eq(-1, funcs.luaeval('vim.stricmp("\\0a\\0", "\\0B\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0A\\0", "\\0b\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0a\\0", "\\0b\\0")'))
+    eq(-1, funcs.luaeval('vim.stricmp("\\0A\\0", "\\0B\\0")'))
+
+    eq(1, funcs.luaeval('vim.stricmp("c", "B")'))
+    eq(1, funcs.luaeval('vim.stricmp("C", "b")'))
+    eq(1, funcs.luaeval('vim.stricmp("c", "b")'))
+    eq(1, funcs.luaeval('vim.stricmp("C", "B")'))
+
+    eq(1, funcs.luaeval('vim.stricmp("\\0", "")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0\\0", "\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0\\0\\0", "\\0\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0\\0\\0\\0", "\\0\\0\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0\\0\\0C", "\\0\\0\\0b")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0\\0\\0c", "\\0\\0\\0B")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0\\0\\0c", "\\0\\0\\0b")'))
+
+    eq(1, funcs.luaeval('vim.stricmp("c\\0", "B\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("C\\0", "b\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("c\\0", "b\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("C\\0", "B\\0")'))
+
+    eq(1, funcs.luaeval('vim.stricmp("c\\0", "B")'))
+    eq(1, funcs.luaeval('vim.stricmp("C\\0", "b")'))
+    eq(1, funcs.luaeval('vim.stricmp("c\\0", "b")'))
+    eq(1, funcs.luaeval('vim.stricmp("C\\0", "B")'))
+
+    eq(1, funcs.luaeval('vim.stricmp("\\0c", "\\0B")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0C", "\\0b")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0c", "\\0b")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0C", "\\0B")'))
+
+    eq(1, funcs.luaeval('vim.stricmp("\\0c\\0", "\\0B\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0C\\0", "\\0b\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0c\\0", "\\0b\\0")'))
+    eq(1, funcs.luaeval('vim.stricmp("\\0C\\0", "\\0B\\0")'))
+  end)
+
+  it('vim.startswith', function()
+    eq(true, funcs.luaeval('vim.startswith("123", "1")'))
+    eq(true, funcs.luaeval('vim.startswith("123", "")'))
+    eq(true, funcs.luaeval('vim.startswith("123", "123")'))
+    eq(true, funcs.luaeval('vim.startswith("", "")'))
+
+    eq(false, funcs.luaeval('vim.startswith("123", " ")'))
+    eq(false, funcs.luaeval('vim.startswith("123", "2")'))
+    eq(false, funcs.luaeval('vim.startswith("123", "1234")'))
+
+    eq("string", type(pcall_err(funcs.luaeval, 'vim.startswith("123", nil)')))
+    eq("string", type(pcall_err(funcs.luaeval, 'vim.startswith(nil, "123")')))
+  end)
+
+  it('vim.endswith', function()
+    eq(true, funcs.luaeval('vim.endswith("123", "3")'))
+    eq(true, funcs.luaeval('vim.endswith("123", "")'))
+    eq(true, funcs.luaeval('vim.endswith("123", "123")'))
+    eq(true, funcs.luaeval('vim.endswith("", "")'))
+
+    eq(false, funcs.luaeval('vim.endswith("123", " ")'))
+    eq(false, funcs.luaeval('vim.endswith("123", "2")'))
+    eq(false, funcs.luaeval('vim.endswith("123", "1234")'))
+
+    eq("string", type(pcall_err(funcs.luaeval, 'vim.endswith("123", nil)')))
+    eq("string", type(pcall_err(funcs.luaeval, 'vim.endswith(nil, "123")')))
+  end)
+
+  it("vim.str_utfindex/str_byteindex", function()
+    exec_lua([[_G.test_text = "xy åäö ɧ 汉语 ↥ 🤦x🦄 å بِيَّ"]])
+    local indicies32 = {[0]=0,1,2,3,5,7,9,10,12,13,16,19,20,23,24,28,29,33,34,35,37,38,40,42,44,46,48}
+    local indicies16 = {[0]=0,1,2,3,5,7,9,10,12,13,16,19,20,23,24,28,28,29,33,33,34,35,37,38,40,42,44,46,48}
+    for i,k in pairs(indicies32) do
+      eq(k, exec_lua("return vim.str_byteindex(_G.test_text, ...)", i), i)
+    end
+    for i,k in pairs(indicies16) do
+      eq(k, exec_lua("return vim.str_byteindex(_G.test_text, ..., true)", i), i)
+    end
+    local i32, i16 = 0, 0
+    for k = 0,48 do
+      if indicies32[i32] < k then
+        i32 = i32 + 1
+      end
+      if indicies16[i16] < k then
+        i16 = i16 + 1
+        if indicies16[i16+1] == indicies16[i16] then
+          i16 = i16 + 1
+        end
+      end
+      eq({i32, i16}, exec_lua("return {vim.str_utfindex(_G.test_text, ...)}", k), k)
+    end
+  end)
+
+  it("vim.schedule", function()
+    exec_lua([[
+      test_table = {}
+      vim.schedule(function()
+        table.insert(test_table, "xx")
+      end)
+      table.insert(test_table, "yy")
+    ]])
+    eq({"yy","xx"}, exec_lua("return test_table"))
+
+    -- Validates args.
+    eq('Error executing lua: vim.schedule: expected function',
+      pcall_err(exec_lua, "vim.schedule('stringly')"))
+    eq('Error executing lua: vim.schedule: expected function',
+      pcall_err(exec_lua, "vim.schedule()"))
+
+    exec_lua([[
+      vim.schedule(function()
+        error("big failure\nvery async")
+      end)
+    ]])
+
+    feed("<cr>")
+    eq('Error executing vim.schedule lua callback: [string "<nvim>"]:2: big failure\nvery async', eval("v:errmsg"))
+
+    local screen = Screen.new(60,5)
+    screen:set_default_attr_ids({
+      [1] = {bold = true, foreground = Screen.colors.Blue1},
+      [2] = {bold = true, reverse = true},
+      [3] = {foreground = Screen.colors.Grey100, background = Screen.colors.Red},
+      [4] = {bold = true, foreground = Screen.colors.SeaGreen4},
+    })
+    screen:attach()
+    screen:expect{grid=[[
+      ^                                                            |
+      {1:~                                                           }|
+      {1:~                                                           }|
+      {1:~                                                           }|
+                                                                  |
+    ]]}
+
+    -- nvim_command causes a vimL exception, check that it is properly caught
+    -- and propagated as an error message in async contexts.. #10809
+    exec_lua([[
+      vim.schedule(function()
+        vim.api.nvim_command(":echo 'err")
+      end)
+    ]])
+    screen:expect{grid=[[
+                                                                  |
+      {2:                                                            }|
+      {3:Error executing vim.schedule lua callback: [string "<nvim>"]}|
+      {3::2: Vim(echo):E115: Missing quote: 'err}                     |
+      {4:Press ENTER or type command to continue}^                     |
+    ]]}
+  end)
+
+  it("vim.split", function()
+    local split = function(str, sep, plain)
+      return exec_lua('return vim.split(...)', str, sep, plain)
+    end
+
+    local tests = {
+      { "a,b", ",", false, { 'a', 'b' } },
+      { ":aa::bb:", ":", false, { '', 'aa', '', 'bb', '' } },
+      { "::ee::ff:", ":", false, { '', '', 'ee', '', 'ff', '' } },
+      { "ab", ".", false, { '', '', '' } },
+      { "a1b2c", "[0-9]", false, { 'a', 'b', 'c' } },
+      { "xy", "", false, { 'x', 'y' } },
+      { "here be dragons", " ", false, { "here", "be", "dragons"} },
+      { "axaby", "ab?", false, { '', 'x', 'y' } },
+      { "f v2v v3v w2w ", "([vw])2%1", false, { 'f ', ' v3v ', ' ' } },
+      { "", "", false, {} },
+      { "", "a", false, { '' } },
+      { "x*yz*oo*l", "*", true, { 'x', 'yz', 'oo', 'l' } },
+    }
+
+    for _, t in ipairs(tests) do
+      eq(t[4], split(t[1], t[2], t[3]))
+    end
+
+    local loops = {
+      { "abc", ".-" },
+    }
+
+    for _, t in ipairs(loops) do
+      matches(".*Infinite loop detected", pcall_err(split, t[1], t[2]))
+    end
+
+    -- Validates args.
+    eq(true, pcall(split, 'string', 'string'))
+    eq('Error executing lua: .../shared.lua: s: expected string, got number',
+      pcall_err(split, 1, 'string'))
+    eq('Error executing lua: .../shared.lua: sep: expected string, got number',
+      pcall_err(split, 'string', 1))
+    eq('Error executing lua: .../shared.lua: plain: expected boolean, got number',
+      pcall_err(split, 'string', 'string', 1))
+  end)
+
+  it('vim.trim', function()
+    local trim = function(s)
+      return exec_lua('return vim.trim(...)', s)
+    end
+
+    local trims = {
+      { "   a", "a" },
+      { " b  ", "b" },
+      { "\tc" , "c" },
+      { "r\n", "r" },
+    }
+
+    for _, t in ipairs(trims) do
+      assert(t[2], trim(t[1]))
+    end
+
+    -- Validates args.
+    eq('Error executing lua: .../shared.lua: s: expected string, got number',
+      pcall_err(trim, 2))
+  end)
+
+  it('vim.inspect', function()
+    -- just make sure it basically works, it has its own test suite
+    local inspect = function(t, opts)
+      return exec_lua('return vim.inspect(...)', t, opts)
+    end
+
+    eq('2', inspect(2))
+    eq('{+a = {+b = 1+}+}',
+       inspect({ a = { b = 1 } }, { newline = '+', indent = '' }))
+
+    -- special value vim.inspect.KEY works
+    eq('{  KEY_a = "x",  KEY_b = "y"}', exec_lua([[
+      return vim.inspect({a="x", b="y"}, {newline = '', process = function(item, path)
+        if path[#path] == vim.inspect.KEY then
+          return 'KEY_'..item
+        end
+        return item
+      end})
+    ]]))
+  end)
+
+  it("vim.deepcopy", function()
+    ok(exec_lua([[
+      local a = { x = { 1, 2 }, y = 5}
+      local b = vim.deepcopy(a)
+
+      return b.x[1] == 1 and b.x[2] == 2 and b.y == 5 and vim.tbl_count(b) == 2
+             and tostring(a) ~= tostring(b)
+    ]]))
+
+    ok(exec_lua([[
+      local a = {}
+      local b = vim.deepcopy(a)
+
+      return vim.tbl_islist(b) and vim.tbl_count(b) == 0 and tostring(a) ~= tostring(b)
+    ]]))
+
+    ok(exec_lua([[
+      local a = vim.empty_dict()
+      local b = vim.deepcopy(a)
+
+      return not vim.tbl_islist(b) and vim.tbl_count(b) == 0
+    ]]))
+
+    ok(exec_lua([[
+      local a = {x = vim.empty_dict(), y = {}}
+      local b = vim.deepcopy(a)
+
+      return not vim.tbl_islist(b.x) and vim.tbl_islist(b.y)
+        and vim.tbl_count(b) == 2
+        and tostring(a) ~= tostring(b)
+    ]]))
+
+    ok(exec_lua([[
+      local f1 = function() return 1 end
+      local f2 = function() return 2 end
+      local t1 = {f = f1}
+      local t2 = vim.deepcopy(t1)
+      t1.f = f2
+      return t1.f() ~= t2.f()
+    ]]))
+
+    eq('Error executing lua: .../shared.lua: Cannot deepcopy object of type thread',
+      pcall_err(exec_lua, [[
+        local thread = coroutine.create(function () return 0 end)
+        local t = {thr = thread}
+        vim.deepcopy(t)
+      ]]))
+  end)
+
+  it('vim.pesc', function()
+    eq('foo%-bar', exec_lua([[return vim.pesc('foo-bar')]]))
+    eq('foo%%%-bar', exec_lua([[return vim.pesc(vim.pesc('foo-bar'))]]))
+
+    -- Validates args.
+    eq('Error executing lua: .../shared.lua: s: expected string, got number',
+      pcall_err(exec_lua, [[return vim.pesc(2)]]))
+  end)
+
+  it('vim.tbl_keys', function()
+    eq({}, exec_lua("return vim.tbl_keys({})"))
+    for _, v in pairs(exec_lua("return vim.tbl_keys({'a', 'b', 'c'})")) do
+      eq(true, exec_lua("return vim.tbl_contains({ 1, 2, 3 }, ...)", v))
+    end
+    for _, v in pairs(exec_lua("return vim.tbl_keys({a=1, b=2, c=3})")) do
+      eq(true, exec_lua("return vim.tbl_contains({ 'a', 'b', 'c' }, ...)", v))
+    end
+  end)
+
+  it('vim.tbl_values', function()
+    eq({}, exec_lua("return vim.tbl_values({})"))
+    for _, v in pairs(exec_lua("return vim.tbl_values({'a', 'b', 'c'})")) do
+      eq(true, exec_lua("return vim.tbl_contains({ 'a', 'b', 'c' }, ...)", v))
+    end
+    for _, v in pairs(exec_lua("return vim.tbl_values({a=1, b=2, c=3})")) do
+      eq(true, exec_lua("return vim.tbl_contains({ 1, 2, 3 }, ...)", v))
+    end
+  end)
+
+  it('vim.tbl_map', function()
+    eq({}, exec_lua([[
+      return vim.tbl_map(function(v) return v * 2 end, {})
+    ]]))
+    eq({2, 4, 6}, exec_lua([[
+      return vim.tbl_map(function(v) return v * 2 end, {1, 2, 3})
+    ]]))
+    eq({{i=2}, {i=4}, {i=6}}, exec_lua([[
+      return vim.tbl_map(function(v) return { i = v.i * 2 } end, {{i=1}, {i=2}, {i=3}})
+    ]]))
+  end)
+
+  it('vim.tbl_filter', function()
+    eq({}, exec_lua([[
+      return vim.tbl_filter(function(v) return (v % 2) == 0 end, {})
+    ]]))
+    eq({2}, exec_lua([[
+      return vim.tbl_filter(function(v) return (v % 2) == 0 end, {1, 2, 3})
+    ]]))
+    eq({{i=2}}, exec_lua([[
+      return vim.tbl_filter(function(v) return (v.i % 2) == 0 end, {{i=1}, {i=2}, {i=3}})
+    ]]))
+  end)
+
+  it('vim.tbl_islist', function()
+    eq(true, exec_lua("return vim.tbl_islist({})"))
+    eq(false, exec_lua("return vim.tbl_islist(vim.empty_dict())"))
+    eq(true, exec_lua("return vim.tbl_islist({'a', 'b', 'c'})"))
+    eq(false, exec_lua("return vim.tbl_islist({'a', '32', a='hello', b='baz'})"))
+    eq(false, exec_lua("return vim.tbl_islist({1, a='hello', b='baz'})"))
+    eq(false, exec_lua("return vim.tbl_islist({a='hello', b='baz', 1})"))
+    eq(false, exec_lua("return vim.tbl_islist({1, 2, nil, a='hello'})"))
+  end)
+
+  it('vim.tbl_isempty', function()
+    eq(true, exec_lua("return vim.tbl_isempty({})"))
+    eq(false, exec_lua("return vim.tbl_isempty({ 1, 2, 3 })"))
+    eq(false, exec_lua("return vim.tbl_isempty({a=1, b=2, c=3})"))
+  end)
+
+  it('vim.tbl_extend', function()
+    ok(exec_lua([[
+      local a = {x = 1}
+      local b = {y = 2}
+      local c = vim.tbl_extend("keep", a, b)
+
+      return c.x == 1 and b.y == 2 and vim.tbl_count(c) == 2
+    ]]))
+
+    ok(exec_lua([[
+      local a = {x = 1}
+      local b = {y = 2}
+      local c = {z = 3}
+      local d = vim.tbl_extend("keep", a, b, c)
+
+      return d.x == 1 and d.y == 2 and d.z == 3 and vim.tbl_count(d) == 3
+    ]]))
+
+    ok(exec_lua([[
+      local a = {x = 1}
+      local b = {x = 3}
+      local c = vim.tbl_extend("keep", a, b)
+
+      return c.x == 1 and vim.tbl_count(c) == 1
+    ]]))
+
+    ok(exec_lua([[
+      local a = {x = 1}
+      local b = {x = 3}
+      local c = vim.tbl_extend("force", a, b)
+
+      return c.x == 3 and vim.tbl_count(c) == 1
+    ]]))
+
+    ok(exec_lua([[
+      local a = vim.empty_dict()
+      local b = {}
+      local c = vim.tbl_extend("keep", a, b)
+
+      return not vim.tbl_islist(c) and vim.tbl_count(c) == 0
+    ]]))
+
+    ok(exec_lua([[
+      local a = {}
+      local b = vim.empty_dict()
+      local c = vim.tbl_extend("keep", a, b)
+
+      return vim.tbl_islist(c) and vim.tbl_count(c) == 0
+    ]]))
+
+    ok(exec_lua([[
+      local a = {x = {a = 1, b = 2}}
+      local b = {x = {a = 2, c = {y = 3}}}
+      local c = vim.tbl_extend("keep", a, b)
+
+      local count = 0
+      for _ in pairs(c) do count = count + 1 end
+
+      return c.x.a == 1 and c.x.b == 2 and c.x.c == nil and count == 1
+    ]]))
+
+    eq('Error executing lua: .../shared.lua: invalid "behavior": nil',
+      pcall_err(exec_lua, [[
+        return vim.tbl_extend()
+      ]])
+    )
+
+    eq('Error executing lua: .../shared.lua: wrong number of arguments (given 1, expected at least 3)',
+      pcall_err(exec_lua, [[
+        return vim.tbl_extend("keep")
+      ]])
+    )
+
+    eq('Error executing lua: .../shared.lua: wrong number of arguments (given 2, expected at least 3)',
+      pcall_err(exec_lua, [[
+        return vim.tbl_extend("keep", {})
+      ]])
+    )
+  end)
+
+  it('vim.tbl_deep_extend', function()
+    ok(exec_lua([[
+      local a = {x = {a = 1, b = 2}}
+      local b = {x = {a = 2, c = {y = 3}}}
+      local c = vim.tbl_deep_extend("keep", a, b)
+
+      local count = 0
+      for _ in pairs(c) do count = count + 1 end
+
+      return c.x.a == 1 and c.x.b == 2 and c.x.c.y == 3 and count == 1
+    ]]))
+
+    ok(exec_lua([[
+      local a = {x = {a = 1, b = 2}}
+      local b = {x = {a = 2, c = {y = 3}}}
+      local c = vim.tbl_deep_extend("force", a, b)
+
+      local count = 0
+      for _ in pairs(c) do count = count + 1 end
+
+      return c.x.a == 2 and c.x.b == 2 and c.x.c.y == 3 and count == 1
+    ]]))
+
+    ok(exec_lua([[
+      local a = {x = {a = 1, b = 2}}
+      local b = {x = {a = 2, c = {y = 3}}}
+      local c = {x = {c = 4, d = {y = 4}}}
+      local d = vim.tbl_deep_extend("keep", a, b, c)
+
+      local count = 0
+      for _ in pairs(c) do count = count + 1 end
+
+      return d.x.a == 1 and d.x.b == 2 and d.x.c.y == 3 and d.x.d.y == 4 and count == 1
+    ]]))
+
+    ok(exec_lua([[
+      local a = {x = {a = 1, b = 2}}
+      local b = {x = {a = 2, c = {y = 3}}}
+      local c = {x = {c = 4, d = {y = 4}}}
+      local d = vim.tbl_deep_extend("force", a, b, c)
+
+      local count = 0
+      for _ in pairs(c) do count = count + 1 end
+
+      return d.x.a == 2 and d.x.b == 2 and d.x.c == 4 and d.x.d.y == 4 and count == 1
+    ]]))
+
+    ok(exec_lua([[
+      local a = vim.empty_dict()
+      local b = {}
+      local c = vim.tbl_deep_extend("keep", a, b)
+
+      local count = 0
+      for _ in pairs(c) do count = count + 1 end
+
+      return not vim.tbl_islist(c) and count == 0
+    ]]))
+
+    ok(exec_lua([[
+      local a = {}
+      local b = vim.empty_dict()
+      local c = vim.tbl_deep_extend("keep", a, b)
+
+      local count = 0
+      for _ in pairs(c) do count = count + 1 end
+
+      return vim.tbl_islist(c) and count == 0
+    ]]))
+
+    eq('Error executing lua: .../shared.lua: invalid "behavior": nil',
+      pcall_err(exec_lua, [[
+        return vim.tbl_deep_extend()
+      ]])
+    )
+
+    eq('Error executing lua: .../shared.lua: wrong number of arguments (given 1, expected at least 3)',
+      pcall_err(exec_lua, [[
+        return vim.tbl_deep_extend("keep")
+      ]])
+    )
+
+    eq('Error executing lua: .../shared.lua: wrong number of arguments (given 2, expected at least 3)',
+      pcall_err(exec_lua, [[
+        return vim.tbl_deep_extend("keep", {})
+      ]])
+    )
+  end)
+
+  it('vim.tbl_count', function()
+    eq(0, exec_lua [[ return vim.tbl_count({}) ]])
+    eq(0, exec_lua [[ return vim.tbl_count(vim.empty_dict()) ]])
+    eq(0, exec_lua [[ return vim.tbl_count({nil}) ]])
+    eq(0, exec_lua [[ return vim.tbl_count({a=nil}) ]])
+    eq(1, exec_lua [[ return vim.tbl_count({1}) ]])
+    eq(2, exec_lua [[ return vim.tbl_count({1, 2}) ]])
+    eq(2, exec_lua [[ return vim.tbl_count({1, nil, 3}) ]])
+    eq(1, exec_lua [[ return vim.tbl_count({a=1}) ]])
+    eq(2, exec_lua [[ return vim.tbl_count({a=1, b=2}) ]])
+    eq(2, exec_lua [[ return vim.tbl_count({a=1, b=nil, c=3}) ]])
+  end)
+
+  it('vim.deep_equal', function()
+    eq(true, exec_lua [[ return vim.deep_equal({a=1}, {a=1}) ]])
+    eq(true, exec_lua [[ return vim.deep_equal({a={b=1}}, {a={b=1}}) ]])
+    eq(true, exec_lua [[ return vim.deep_equal({a={b={nil}}}, {a={b={}}}) ]])
+    eq(true, exec_lua [[ return vim.deep_equal({a=1, [5]=5}, {nil,nil,nil,nil,5,a=1}) ]])
+    eq(false, exec_lua [[ return vim.deep_equal(1, {nil,nil,nil,nil,5,a=1}) ]])
+    eq(false, exec_lua [[ return vim.deep_equal(1, 3) ]])
+    eq(false, exec_lua [[ return vim.deep_equal(nil, 3) ]])
+    eq(false, exec_lua [[ return vim.deep_equal({a=1}, {a=2}) ]])
+  end)
+
+  it('vim.list_extend', function()
+    eq({1,2,3}, exec_lua [[ return vim.list_extend({1}, {2,3}) ]])
+    eq('Error executing lua: .../shared.lua: src: expected table, got nil',
+      pcall_err(exec_lua, [[ return vim.list_extend({1}, nil) ]]))
+    eq({1,2}, exec_lua [[ return vim.list_extend({1}, {2;a=1}) ]])
+    eq(true, exec_lua [[ local a = {1} return vim.list_extend(a, {2;a=1}) == a ]])
+    eq({2}, exec_lua [[ return vim.list_extend({}, {2;a=1}, 1) ]])
+    eq({}, exec_lua [[ return vim.list_extend({}, {2;a=1}, 2) ]])
+    eq({}, exec_lua [[ return vim.list_extend({}, {2;a=1}, 1, -1) ]])
+    eq({2}, exec_lua [[ return vim.list_extend({}, {2;a=1}, -1, 2) ]])
+  end)
+
+  it('vim.tbl_add_reverse_lookup', function()
+    eq(true, exec_lua [[
+    local a = { A = 1 }
+    vim.tbl_add_reverse_lookup(a)
+    return vim.deep_equal(a, { A = 1; [1] = 'A'; })
+    ]])
+    -- Throw an error for trying to do it twice (run into an existing key)
+    local code = [[
+    local res = {}
+    local a = { A = 1 }
+    vim.tbl_add_reverse_lookup(a)
+    assert(vim.deep_equal(a, { A = 1; [1] = 'A'; }))
+    vim.tbl_add_reverse_lookup(a)
+    ]]
+    matches('Error executing lua: .../shared.lua: The reverse lookup found an existing value for "[1A]" while processing key "[1A]"',
+      pcall_err(exec_lua, code))
+  end)
+
+  it('vim.call, vim.fn', function()
+    eq(true, exec_lua([[return vim.call('sin', 0.0) == 0.0 ]]))
+    eq(true, exec_lua([[return vim.fn.sin(0.0) == 0.0 ]]))
+    -- compat: nvim_call_function uses "special" value for vimL float
+    eq(false, exec_lua([[return vim.api.nvim_call_function('sin', {0.0}) == 0.0 ]]))
+
+    source([[
+      func! FooFunc(test)
+        let g:test = a:test
+        return {}
+      endfunc
+      func! VarArg(...)
+        return a:000
+      endfunc
+      func! Nilly()
+        return [v:null, v:null]
+      endfunc
+    ]])
+    eq(true, exec_lua([[return next(vim.fn.FooFunc(3)) == nil ]]))
+    eq(3, eval("g:test"))
+    -- compat: nvim_call_function uses "special" value for empty dict
+    eq(true, exec_lua([[return next(vim.api.nvim_call_function("FooFunc", {5})) == true ]]))
+    eq(5, eval("g:test"))
+
+    eq({2, "foo", true}, exec_lua([[return vim.fn.VarArg(2, "foo", true)]]))
+
+    eq(true, exec_lua([[
+      local x = vim.fn.Nilly()
+      return #x == 2 and x[1] == vim.NIL and x[2] == vim.NIL
+    ]]))
+    eq({NIL, NIL}, exec_lua([[return vim.fn.Nilly()]]))
+
+    -- error handling
+    eq({false, 'Vim:E714: List required'}, exec_lua([[return {pcall(vim.fn.add, "aa", "bb")}]]))
+  end)
+
+  it('vim.rpcrequest and vim.rpcnotify', function()
+    exec_lua([[
+      chan = vim.fn.jobstart({'cat'}, {rpc=true})
+      vim.rpcrequest(chan, 'nvim_set_current_line', 'meow')
+    ]])
+    eq('meow', meths.get_current_line())
+    command("let x = [3, 'aa', v:true, v:null]")
+    eq(true, exec_lua([[
+      ret = vim.rpcrequest(chan, 'nvim_get_var', 'x')
+      return #ret == 4 and ret[1] == 3 and ret[2] == 'aa' and ret[3] == true and ret[4] == vim.NIL
+    ]]))
+    eq({3, 'aa', true, NIL}, exec_lua([[return ret]]))
+
+    eq({{}, {}, false, true}, exec_lua([[
+      vim.rpcrequest(chan, 'nvim_exec', 'let xx = {}\nlet yy = []', false)
+      local dict = vim.rpcrequest(chan, 'nvim_eval', 'xx')
+      local list = vim.rpcrequest(chan, 'nvim_eval', 'yy')
+      return {dict, list, vim.tbl_islist(dict), vim.tbl_islist(list)}
+     ]]))
+
+     exec_lua([[
+       vim.rpcrequest(chan, 'nvim_set_var', 'aa', {})
+       vim.rpcrequest(chan, 'nvim_set_var', 'bb', vim.empty_dict())
+     ]])
+     eq({1, 1}, eval('[type(g:aa) == type([]), type(g:bb) == type({})]'))
+
+    -- error handling
+    eq({false, 'Invalid channel: 23'},
+       exec_lua([[return {pcall(vim.rpcrequest, 23, 'foo')}]]))
+    eq({false, 'Invalid channel: 23'},
+       exec_lua([[return {pcall(vim.rpcnotify, 23, 'foo')}]]))
+
+    eq({false, 'Vim:E121: Undefined variable: foobar'},
+       exec_lua([[return {pcall(vim.rpcrequest, chan, 'nvim_eval', "foobar")}]]))
+
+
+    -- rpcnotify doesn't wait on request
+    eq('meow', exec_lua([[
+      vim.rpcnotify(chan, 'nvim_set_current_line', 'foo')
+      return vim.api.nvim_get_current_line()
+    ]]))
+    retry(10, nil, function()
+      eq('foo', meths.get_current_line())
+    end)
+
+    local screen = Screen.new(50,7)
+    screen:set_default_attr_ids({
+      [1] = {bold = true, foreground = Screen.colors.Blue1},
+      [2] = {bold = true, reverse = true},
+      [3] = {foreground = Screen.colors.Grey100, background = Screen.colors.Red},
+      [4] = {bold = true, foreground = Screen.colors.SeaGreen4},
+    })
+    screen:attach()
+    exec_lua([[
+      timer = vim.loop.new_timer()
+      timer:start(20, 0, function ()
+        -- notify ok (executed later when safe)
+        vim.rpcnotify(chan, 'nvim_set_var', 'yy', {3, vim.NIL})
+        -- rpcrequest an error
+        vim.rpcrequest(chan, 'nvim_set_current_line', 'bork')
+      end)
+    ]])
+    screen:expect{grid=[[
+      foo                                               |
+      {1:~                                                 }|
+      {2:                                                  }|
+      {3:Error executing luv callback:}                     |
+      {3:[string "<nvim>"]:6: E5560: rpcrequest must not be}|
+      {3: called in a lua loop callback}                    |
+      {4:Press ENTER or type command to continue}^           |
+    ]]}
+    feed('<cr>')
+    eq({3, NIL}, meths.get_var('yy'))
+
+    exec_lua([[timer:close()]])
+  end)
+
+  it('vim.empty_dict()', function()
+    eq({true, false, true, true}, exec_lua([[
+      vim.api.nvim_set_var('listy', {})
+      vim.api.nvim_set_var('dicty', vim.empty_dict())
+      local listy = vim.fn.eval("listy")
+      local dicty = vim.fn.eval("dicty")
+      return {vim.tbl_islist(listy), vim.tbl_islist(dicty), next(listy) == nil, next(dicty) == nil}
+    ]]))
+
+    -- vim.empty_dict() gives new value each time
+    -- equality is not overriden (still by ref)
+    -- non-empty table uses the usual heuristics (ignores the tag)
+    eq({false, {"foo"}, {namey="bar"}}, exec_lua([[
+      local aa = vim.empty_dict()
+      local bb = vim.empty_dict()
+      local equally = (aa == bb)
+      aa[1] = "foo"
+      bb["namey"] = "bar"
+      return {equally, aa, bb}
+    ]]))
+
+    eq("{ {}, vim.empty_dict() }", exec_lua("return vim.inspect({{}, vim.empty_dict()})"))
+    eq('{}', exec_lua([[ return vim.fn.json_encode(vim.empty_dict()) ]]))
+    eq('{"a": {}, "b": []}', exec_lua([[ return vim.fn.json_encode({a=vim.empty_dict(), b={}}) ]]))
+  end)
+
+  it('vim.validate', function()
+    exec_lua("vim.validate{arg1={{}, 'table' }}")
+    exec_lua("vim.validate{arg1={{}, 't' }}")
+    exec_lua("vim.validate{arg1={nil, 't', true }}")
+    exec_lua("vim.validate{arg1={{ foo='foo' }, 't' }}")
+    exec_lua("vim.validate{arg1={{ 'foo' }, 't' }}")
+    exec_lua("vim.validate{arg1={'foo', 'string' }}")
+    exec_lua("vim.validate{arg1={'foo', 's' }}")
+    exec_lua("vim.validate{arg1={'', 's' }}")
+    exec_lua("vim.validate{arg1={nil, 's', true }}")
+    exec_lua("vim.validate{arg1={1, 'number' }}")
+    exec_lua("vim.validate{arg1={1, 'n' }}")
+    exec_lua("vim.validate{arg1={0, 'n' }}")
+    exec_lua("vim.validate{arg1={0.1, 'n' }}")
+    exec_lua("vim.validate{arg1={nil, 'n', true }}")
+    exec_lua("vim.validate{arg1={true, 'boolean' }}")
+    exec_lua("vim.validate{arg1={true, 'b' }}")
+    exec_lua("vim.validate{arg1={false, 'b' }}")
+    exec_lua("vim.validate{arg1={nil, 'b', true }}")
+    exec_lua("vim.validate{arg1={function()end, 'function' }}")
+    exec_lua("vim.validate{arg1={function()end, 'f' }}")
+    exec_lua("vim.validate{arg1={nil, 'f', true }}")
+    exec_lua("vim.validate{arg1={nil, 'nil' }}")
+    exec_lua("vim.validate{arg1={nil, 'nil', true }}")
+    exec_lua("vim.validate{arg1={coroutine.create(function()end), 'thread' }}")
+    exec_lua("vim.validate{arg1={nil, 'thread', true }}")
+    exec_lua("vim.validate{arg1={{}, 't' }, arg2={ 'foo', 's' }}")
+    exec_lua("vim.validate{arg1={2, function(a) return (a % 2) == 0  end, 'even number' }}")
+
+    eq("Error executing lua: .../shared.lua: 1: expected table, got number",
+      pcall_err(exec_lua, "vim.validate{ 1, 'x' }"))
+    eq("Error executing lua: .../shared.lua: invalid type name: x",
+      pcall_err(exec_lua, "vim.validate{ arg1={ 1, 'x' }}"))
+    eq("Error executing lua: .../shared.lua: invalid type name: 1",
+      pcall_err(exec_lua, "vim.validate{ arg1={ 1, 1 }}"))
+    eq("Error executing lua: .../shared.lua: invalid type name: nil",
+      pcall_err(exec_lua, "vim.validate{ arg1={ 1 }}"))
+
+    -- Validated parameters are required by default.
+    eq("Error executing lua: .../shared.lua: arg1: expected string, got nil",
+      pcall_err(exec_lua, "vim.validate{ arg1={ nil, 's' }}"))
+    -- Explicitly required.
+    eq("Error executing lua: .../shared.lua: arg1: expected string, got nil",
+      pcall_err(exec_lua, "vim.validate{ arg1={ nil, 's', false }}"))
+
+    eq("Error executing lua: .../shared.lua: arg1: expected table, got number",
+      pcall_err(exec_lua, "vim.validate{arg1={1, 't'}}"))
+    eq("Error executing lua: .../shared.lua: arg2: expected string, got number",
+      pcall_err(exec_lua, "vim.validate{arg1={{}, 't'}, arg2={1, 's'}}"))
+    eq("Error executing lua: .../shared.lua: arg2: expected string, got nil",
+      pcall_err(exec_lua, "vim.validate{arg1={{}, 't'}, arg2={nil, 's'}}"))
+    eq("Error executing lua: .../shared.lua: arg2: expected string, got nil",
+      pcall_err(exec_lua, "vim.validate{arg1={{}, 't'}, arg2={nil, 's'}}"))
+    eq("Error executing lua: .../shared.lua: arg1: expected even number, got 3",
+      pcall_err(exec_lua, "vim.validate{arg1={3, function(a) return a == 1 end, 'even number'}}"))
+    eq("Error executing lua: .../shared.lua: arg1: expected ?, got 3",
+      pcall_err(exec_lua, "vim.validate{arg1={3, function(a) return a == 1 end}}"))
+  end)
+
+  it('vim.is_callable', function()
+    eq(true, exec_lua("return vim.is_callable(function()end)"))
+    eq(true, exec_lua([[
+      local meta = { __call = function()end }
+      local function new_callable()
+        return setmetatable({}, meta)
+      end
+      local callable = new_callable()
+      return vim.is_callable(callable)
+    ]]))
+
+    eq(false, exec_lua("return vim.is_callable(1)"))
+    eq(false, exec_lua("return vim.is_callable('foo')"))
+    eq(false, exec_lua("return vim.is_callable({})"))
+  end)
+
+  it('vim.g', function()
+    exec_lua [[
+    vim.api.nvim_set_var("testing", "hi")
+    vim.api.nvim_set_var("other", 123)
+    vim.api.nvim_set_var("to_delete", {hello="world"})
+    ]]
+
+    eq('hi', funcs.luaeval "vim.g.testing")
+    eq(123, funcs.luaeval "vim.g.other")
+    eq(NIL, funcs.luaeval "vim.g.nonexistant")
+
+    eq({hello="world"}, funcs.luaeval "vim.g.to_delete")
+    exec_lua [[
+    vim.g.to_delete = nil
+    ]]
+    eq(NIL, funcs.luaeval "vim.g.to_delete")
+  end)
+
+  it('vim.b', function()
+    exec_lua [[
+    vim.api.nvim_buf_set_var(0, "testing", "hi")
+    vim.api.nvim_buf_set_var(0, "other", 123)
+    vim.api.nvim_buf_set_var(0, "to_delete", {hello="world"})
+    ]]
+
+    eq('hi', funcs.luaeval "vim.b.testing")
+    eq(123, funcs.luaeval "vim.b.other")
+    eq(NIL, funcs.luaeval "vim.b.nonexistant")
+
+    eq({hello="world"}, funcs.luaeval "vim.b.to_delete")
+    exec_lua [[
+    vim.b.to_delete = nil
+    ]]
+    eq(NIL, funcs.luaeval "vim.b.to_delete")
+
+    exec_lua [[
+    vim.cmd "vnew"
+    ]]
+
+    eq(NIL, funcs.luaeval "vim.b.testing")
+    eq(NIL, funcs.luaeval "vim.b.other")
+    eq(NIL, funcs.luaeval "vim.b.nonexistant")
+  end)
+
+  it('vim.w', function()
+    exec_lua [[
+    vim.api.nvim_win_set_var(0, "testing", "hi")
+    vim.api.nvim_win_set_var(0, "other", 123)
+    vim.api.nvim_win_set_var(0, "to_delete", {hello="world"})
+    ]]
+
+    eq('hi', funcs.luaeval "vim.w.testing")
+    eq(123, funcs.luaeval "vim.w.other")
+    eq(NIL, funcs.luaeval "vim.w.nonexistant")
+
+    eq({hello="world"}, funcs.luaeval "vim.w.to_delete")
+    exec_lua [[
+    vim.w.to_delete = nil
+    ]]
+    eq(NIL, funcs.luaeval "vim.w.to_delete")
+
+    exec_lua [[
+    vim.cmd "vnew"
+    ]]
+
+    eq(NIL, funcs.luaeval "vim.w.testing")
+    eq(NIL, funcs.luaeval "vim.w.other")
+    eq(NIL, funcs.luaeval "vim.w.nonexistant")
+  end)
+
+  it('vim.t', function()
+    exec_lua [[
+    vim.api.nvim_tabpage_set_var(0, "testing", "hi")
+    vim.api.nvim_tabpage_set_var(0, "other", 123)
+    vim.api.nvim_tabpage_set_var(0, "to_delete", {hello="world"})
+    ]]
+
+    eq('hi', funcs.luaeval "vim.t.testing")
+    eq(123, funcs.luaeval "vim.t.other")
+    eq(NIL, funcs.luaeval "vim.t.nonexistant")
+
+    eq({hello="world"}, funcs.luaeval "vim.t.to_delete")
+    exec_lua [[
+    vim.t.to_delete = nil
+    ]]
+    eq(NIL, funcs.luaeval "vim.t.to_delete")
+
+    exec_lua [[
+    vim.cmd "tabnew"
+    ]]
+
+    eq(NIL, funcs.luaeval "vim.t.testing")
+    eq(NIL, funcs.luaeval "vim.t.other")
+    eq(NIL, funcs.luaeval "vim.t.nonexistant")
+  end)
+
+  it('vim.env', function()
+    exec_lua [[
+    vim.fn.setenv("A", 123)
+    ]]
+    eq('123', funcs.luaeval "vim.env.A")
+    eq(true, funcs.luaeval "vim.env.B == nil")
+  end)
+
+  it('vim.v', function()
+    eq(funcs.luaeval "vim.api.nvim_get_vvar('progpath')", funcs.luaeval "vim.v.progpath")
+    eq(false, funcs.luaeval "vim.v['false']")
+    eq(NIL, funcs.luaeval "vim.v.null")
+  end)
+
+  it('vim.bo', function()
+    eq('', funcs.luaeval "vim.bo.filetype")
+    exec_lua [[
+    vim.api.nvim_buf_set_option(0, "filetype", "markdown")
+    BUF = vim.api.nvim_create_buf(false, true)
+    vim.api.nvim_buf_set_option(BUF, "modifiable", false)
+    ]]
+    eq(false, funcs.luaeval "vim.bo.modified")
+    eq('markdown', funcs.luaeval "vim.bo.filetype")
+    eq(false, funcs.luaeval "vim.bo[BUF].modifiable")
+    exec_lua [[
+    vim.bo.filetype = ''
+    vim.bo[BUF].modifiable = true
+    ]]
+    eq('', funcs.luaeval "vim.bo.filetype")
+    eq(true, funcs.luaeval "vim.bo[BUF].modifiable")
+    matches("^Error executing lua: .*: Invalid option name: 'nosuchopt'$",
+       pcall_err(exec_lua, 'return vim.bo.nosuchopt'))
+    matches("^Error executing lua: .*: Expected lua string$",
+       pcall_err(exec_lua, 'return vim.bo[0][0].autoread'))
+  end)
+
+  it('vim.wo', function()
+    exec_lua [[
+    vim.api.nvim_win_set_option(0, "cole", 2)
+    vim.cmd "split"
+    vim.api.nvim_win_set_option(0, "cole", 2)
+    ]]
+    eq(2, funcs.luaeval "vim.wo.cole")
+    exec_lua [[
+    vim.wo.conceallevel = 0
+    ]]
+    eq(0, funcs.luaeval "vim.wo.cole")
+    eq(0, funcs.luaeval "vim.wo[0].cole")
+    eq(0, funcs.luaeval "vim.wo[1001].cole")
+    matches("^Error executing lua: .*: Invalid option name: 'notanopt'$",
+       pcall_err(exec_lua, 'return vim.wo.notanopt'))
+    matches("^Error executing lua: .*: Expected lua string$",
+       pcall_err(exec_lua, 'return vim.wo[0][0].list'))
+    eq(2, funcs.luaeval "vim.wo[1000].cole")
+    exec_lua [[
+    vim.wo[1000].cole = 0
+    ]]
+    eq(0, funcs.luaeval "vim.wo[1000].cole")
+  end)
+
+  it('vim.cmd', function()
+    exec_lua [[
+    vim.cmd "autocmd BufNew * ++once lua BUF = vim.fn.expand('<abuf>')"
+    vim.cmd "new"
+    ]]
+    eq('2', funcs.luaeval "BUF")
+    eq(2, funcs.luaeval "#vim.api.nvim_list_bufs()")
+  end)
+
+  it('vim.regex', function()
+    exec_lua [[
+      re1 = vim.regex"ab\\+c"
+      vim.cmd "set nomagic ignorecase"
+      re2 = vim.regex"xYz"
+    ]]
+    eq({}, exec_lua[[return {re1:match_str("x ac")}]])
+    eq({3,7}, exec_lua[[return {re1:match_str("ac abbc")}]])
+
+    meths.buf_set_lines(0, 0, -1, true, {"yy", "abc abbc"})
+    eq({}, exec_lua[[return {re1:match_line(0, 0)}]])
+    eq({0,3}, exec_lua[[return {re1:match_line(0, 1)}]])
+    eq({3,7}, exec_lua[[return {re1:match_line(0, 1, 1)}]])
+    eq({3,7}, exec_lua[[return {re1:match_line(0, 1, 1, 8)}]])
+    eq({}, exec_lua[[return {re1:match_line(0, 1, 1, 7)}]])
+    eq({0,3}, exec_lua[[return {re1:match_line(0, 1, 0, 7)}]])
+  end)
+
+  it('vim.defer_fn', function()
+    eq(false, exec_lua [[
+      vim.g.test = false
+      vim.defer_fn(function() vim.g.test = true end, 150)
+      return vim.g.test
+    ]])
+    exec_lua [[vim.wait(1000, function() return vim.g.test end)]]
+    eq(true, exec_lua[[return vim.g.test]])
+  end)
+
+  it('vim.region', function()
+    helpers.insert(helpers.dedent( [[
+    text tααt tααt text
+    text tαxt txtα tex
+    text tαxt tαxt
+    ]]))
+    eq({5,15}, exec_lua[[ return vim.region(0,{1,5},{1,14},'v',true)[1] ]])
+  end)
+
+  describe('vim.wait', function()
+    before_each(function()
+      exec_lua[[
+        -- high precision timer
+        get_time = function()
+          return vim.fn.reltimefloat(vim.fn.reltime())
+        end
+      ]]
+    end)
+
+    it('should run from lua', function()
+      exec_lua[[vim.wait(100, function() return true end)]]
+    end)
+
+    it('should wait the expected time if false', function()
+      eq({time = true, wait_result = {false, -1}}, exec_lua[[
+        start_time = get_time()
+        wait_succeed, wait_fail_val = vim.wait(200, function() return false end)
+
+        return {
+          -- 150ms waiting or more results in true. Flaky tests are bad.
+          time = (start_time + 0.15) < get_time(),
+          wait_result = {wait_succeed, wait_fail_val}
+        }
+      ]])
+    end)
+
+
+    it('should not block other events', function()
+      eq({time = true, wait_result = true}, exec_lua[[
+        start_time = get_time()
+
+        vim.g.timer_result = false
+        timer = vim.loop.new_timer()
+        timer:start(100, 0, vim.schedule_wrap(function()
+          vim.g.timer_result = true
+        end))
+
+        -- Would wait ten seconds if results blocked.
+        wait_result = vim.wait(10000, function() return vim.g.timer_result end)
+
+        return {
+          time = (start_time + 5) > get_time(),
+          wait_result = wait_result,
+        }
+      ]])
+    end)
+
+    it('should work with vim.defer_fn', function()
+      eq({time = true, wait_result = true}, exec_lua[[
+        start_time = get_time()
+
+        vim.defer_fn(function() vim.g.timer_result = true end, 100)
+        wait_result = vim.wait(10000, function() return vim.g.timer_result end)
+
+        return {
+          time = (start_time + 5) > get_time(),
+          wait_result = wait_result,
+        }
+      ]])
+    end)
+
+    it('should require functions to be passed', function()
+      local pcall_result = exec_lua [[
+        return {pcall(function() vim.wait(1000, 13) end)}
+      ]]
+
+      eq(pcall_result[1], false)
+      matches('condition must be a function', pcall_result[2])
+    end)
+
+    it('should not crash when callback errors', function()
+      local pcall_result = exec_lua [[
+        return {pcall(function() vim.wait(1000, function() error("As Expected") end) end)}
+      ]]
+
+      eq(pcall_result[1], false)
+      matches('As Expected', pcall_result[2])
+    end)
+
+    it('should call callbacks exactly once if they return true immediately', function()
+      eq(true, exec_lua [[
+        vim.g.wait_count = 0
+        vim.wait(1000, function()
+          vim.g.wait_count = vim.g.wait_count + 1
+          return true
+        end, 20)
+        return vim.g.wait_count == 1
+      ]])
+    end)
+
+    it('should call callbacks few times with large `interval`', function()
+      eq(true, exec_lua [[
+        vim.g.wait_count = 0
+        vim.wait(50, function() vim.g.wait_count = vim.g.wait_count + 1 end, 200)
+        return vim.g.wait_count < 5
+      ]])
+    end)
+
+    it('should play nice with `not` when fails', function()
+      eq(true, exec_lua [[
+        if not vim.wait(50, function() end) then
+          return true
+        end
+
+        return false
+      ]])
+    end)
+
+    it('should play nice with `if` when success', function()
+      eq(true, exec_lua [[
+        if vim.wait(50, function() return true end) then
+          return true
+        end
+
+        return false
+      ]])
+    end)
+
+    it('should return immediately with false if timeout is 0', function()
+      eq({false, -1}, exec_lua [[
+        return {
+          vim.wait(0, function() return false end)
+        }
+      ]])
+    end)
+
+    it('should work with tables with __call', function()
+      eq(true, exec_lua [[
+        local t = setmetatable({}, {__call = function(...) return true end})
+        return vim.wait(100, t, 10)
+      ]])
+    end)
+
+    it('should work with tables with __call that change', function()
+      eq(true, exec_lua [[
+        local t = {count = 0}
+        setmetatable(t, {
+          __call = function()
+            t.count = t.count + 1
+            return t.count > 3
+          end
+        })
+
+        return vim.wait(1000, t, 10)
+      ]])
+    end)
+
+    it('should not work with negative intervals', function()
+      local pcall_result = exec_lua [[
+        return pcall(function() vim.wait(1000, function() return false end, -1) end)
+      ]]
+
+      eq(false, pcall_result)
+    end)
+
+    it('should not work with weird intervals', function()
+      local pcall_result = exec_lua [[
+        return pcall(function() vim.wait(1000, function() return false end, 'a string value') end)
+      ]]
+
+      eq(false, pcall_result)
+    end)
+  end)
+end)