patch 8.2.1105: insufficient test coverage for Lua

Problem:    Insufficient test coverage for Lua.
Solution:   Add tests. (Yegappan Lakshmanan, closes #6368)  Fix uncovered
            memory leak.  Avoid unnecessary copy/free.

src/if_lua.c

@@ -936,8 +936,7 @@ luaV_list_newindex(lua_State *L)
 	    typval_T v;
 	    luaV_checktypval(L, 3, &v, "setting list item");
 	    clear_tv(&li->li_tv);
-	    copy_tv(&v, &li->li_tv);
+	    li->li_tv = v;
-	    clear_tv(&v);
         }
     }
     return 0;
@@ -1084,7 +1083,7 @@ luaV_dict_newindex(lua_State *L)
     dict_T *d = luaV_unbox(L, luaV_Dict, 1);
     char_u *key = (char_u *) luaL_checkstring(L, 2);
     dictitem_T *di;
-    typval_T v;
+    typval_T tv;
 
     if (d->dv_lock)
 	luaL_error(L, "dict is locked");
@@ -1094,9 +1093,12 @@ luaV_dict_newindex(lua_State *L)
 	luaL_error(L, "empty key");
     if (!lua_isnil(L, 3)) // read value?
     {
-	luaV_checktypval(L, 3, &v, "setting dict item");
+	luaV_checktypval(L, 3, &tv, "setting dict item");
-	if (d->dv_scope == VAR_DEF_SCOPE && v.v_type == VAR_FUNC)
+	if (d->dv_scope == VAR_DEF_SCOPE && tv.v_type == VAR_FUNC)
+	{
+	    clear_tv(&tv);
 	    luaL_error(L, "cannot assign funcref to builtin scope");
+	}
     }
     di = dict_find(d, key, -1);
     if (di == NULL) // non-existing key?
@@ -1105,10 +1107,14 @@ luaV_dict_newindex(lua_State *L)
 	    return 0;
 	di = dictitem_alloc(key);
 	if (di == NULL)
+	{
+	    clear_tv(&tv);
 	    return 0;
+	}
 	if (dict_add(d, di) == FAIL)
 	{
 	    vim_free(di);
+	    clear_tv(&tv);
 	    return 0;
 	}
     }
@@ -1121,10 +1127,7 @@ luaV_dict_newindex(lua_State *L)
 	dictitem_free(di);
     }
     else
-    {
+	di->di_tv = tv;
-	copy_tv(&v, &di->di_tv);
-	clear_tv(&v);
-    }
     return 0;
 }
 
@@ -1441,7 +1444,8 @@ luaV_buffer_newindex(lua_State *L)
 			curwin->w_cursor.lnum -= 1;
 			check_cursor_col();
 		    }
-		    else check_cursor();
+		    else
+			check_cursor();
 		    changed_cline_bef_curs();
 		}
 		invalidate_botline();
@@ -1842,8 +1846,7 @@ luaV_dict(lua_State *L)
 		    lua_pushnil(L);
 		    return 1;
 		}
-		copy_tv(&v, &di->di_tv);
+		di->di_tv = v;
-		clear_tv(&v);
 		lua_pop(L, 2); // key copy and value
 	    }
 	}
@@ -2398,7 +2401,7 @@ ex_luado(exarg_T *eap)
     lua_replace(L, -2); // function -> body
     for (l = eap->line1; l <= eap->line2; l++)
     {
-	// Check the line number, the command my have deleted lines.
+	// Check the line number, the command may have deleted lines.
 	if (l > curbuf->b_ml.ml_line_count)
 	    break;
 

src/testdir/test_lua.vim

@@ -4,6 +4,15 @@ source check.vim
 CheckFeature lua
 CheckFeature float
 
+let s:luaver = split(split(luaeval('_VERSION'), ' ')[1], '\.')
+let s:major = str2nr(s:luaver[0])
+let s:minor = str2nr(s:luaver[1])
+if s:major < 5 || (s:major == 5 && s:minor < 3)
+  let s:lua_53_or_later = 0
+else
+  let s:lua_53_or_later = 1
+endif
+
 func TearDown()
   " Run garbage collection after each test to exercise luaV_setref().
   call test_garbagecollect_now()
@@ -28,6 +37,23 @@ func Test_lua_command()
   bwipe!
 endfunc
 
+func Test_lua_luado()
+  new
+  call setline(1, ['one', 'two'])
+  luado return(linenr)
+  call assert_equal(['1', '2'], getline(1, '$'))
+  close!
+
+  " Error cases
+  call assert_fails('luado string.format()',
+        \ "[string \"vim chunk\"]:1: bad argument #1 to 'format' (string expected, got no value)")
+  call assert_fails('luado func()',
+        \ s:lua_53_or_later
+        \ ? "[string \"vim chunk\"]:1: attempt to call a nil value (global 'func')"
+        \ : "[string \"vim chunk\"]:1: attempt to call global 'func' (a nil value)")
+  call assert_fails('luado error("failed")', "[string \"vim chunk\"]:1: failed")
+endfunc
+
 " Test vim.eval()
 func Test_lua_eval()
   " lua.eval with a number
@@ -55,6 +81,24 @@ func Test_lua_eval()
   call assert_equal('blob', luaeval('vim.type(v)'))
   call assert_equal(0z00112233.deadbeef, luaeval('v'))
 
+  " lua.eval with a float
+  lua v = vim.eval('3.14')
+  call assert_equal('number', luaeval('vim.type(v)'))
+  call assert_equal(3.14, luaeval('v'))
+
+  " lua.eval with a bool
+  lua v = vim.eval('v:true')
+  call assert_equal('number', luaeval('vim.type(v)'))
+  call assert_equal(1, luaeval('v'))
+  lua v = vim.eval('v:false')
+  call assert_equal('number', luaeval('vim.type(v)'))
+  call assert_equal(0, luaeval('v'))
+
+  " lua.eval with a null
+  lua v = vim.eval('v:null')
+  call assert_equal('nil', luaeval('vim.type(v)'))
+  call assert_equal(v:null, luaeval('v'))
+
   call assert_fails('lua v = vim.eval(nil)',
         \ "[string \"vim chunk\"]:1: bad argument #1 to 'eval' (string expected, got nil)")
   call assert_fails('lua v = vim.eval(true)',
@@ -82,6 +126,13 @@ func Test_lua_window()
   " Window 3 does not exist so vim.window(3) should return nil
   call assert_equal('nil', luaeval('tostring(vim.window(3))'))
 
+  call assert_fails("let n = luaeval('vim.window().xyz()')",
+        \ s:lua_53_or_later
+        \ ? "[string \"luaeval\"]:1: attempt to call a nil value (field 'xyz')"
+        \ : "[string \"luaeval\"]:1: attempt to call field 'xyz' (a nil value)")
+  call assert_fails('lua vim.window().xyz = 1',
+        \ "[string \"vim chunk\"]:1: invalid window property: `xyz'")
+
   %bwipe!
 endfunc
 
@@ -125,6 +176,15 @@ endfunc
 func Test_lua_call()
   call assert_equal(has('lua'), luaeval('vim.call("has", "lua")'))
   call assert_equal(printf("Hello %s", "vim"), luaeval('vim.call("printf", "Hello %s", "vim")'))
+
+  " Error cases
+  call assert_fails("call luaeval('vim.call(\"min\", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21)')",
+        \ '[string "luaeval"]:1: Function called with too many arguments')
+  lua co = coroutine.create(function () print("hi") end)
+  call assert_fails("call luaeval('vim.call(\"type\", co)')",
+        \ '[string "luaeval"]:1: lua: cannot convert value')
+  lua co = nil
+  call assert_fails("call luaeval('vim.call(\"abc\")')", '[string "luaeval"]:1: lua: call_vim_function failed')
 endfunc
 
 " Test vim.fn.*
@@ -245,6 +305,15 @@ func Test_lua_buffer_insert()
   lua vim.buffer():insert('4', 10)
 
   call assert_equal(['1', '2', '3', '4'], getline(1, '$'))
+  call assert_equal('4', luaeval('vim.buffer()[4]'))
+  call assert_equal(v:null, luaeval('vim.buffer()[5]'))
+  call assert_equal(v:null, luaeval('vim.buffer()[{}]'))
+  call assert_fails('lua vim.buffer():xyz()',
+        \ s:lua_53_or_later
+        \ ? "[string \"vim chunk\"]:1: attempt to call a nil value (method 'xyz')"
+        \ : "[string \"vim chunk\"]:1: attempt to call method 'xyz' (a nil value)")
+  call assert_fails('lua vim.buffer()[1] = {}',
+        \ '[string "vim chunk"]:1: wrong argument to change')
   bwipe!
 endfunc
 
@@ -252,6 +321,7 @@ endfunc
 func Test_lua_buffer_delete()
   new
   call setline(1, ['1', '2', '3'])
+  call cursor(3, 1)
   lua vim.buffer()[2] = nil
   call assert_equal(['1', '3'], getline(1, '$'))
 
@@ -331,10 +401,26 @@ func Test_lua_list()
   lua l[6] = nil
   lua l:insert('first')
   lua l:insert('xx', 3)
+  call assert_fails('lua l:insert("xx", -20)',
+        \ '[string "vim chunk"]:1: invalid position')
   call assert_equal(['first', 124, 'abc', 'xx', v:true, v:false, v:null, {'a': 1, 'b': 2, 'c': 3}], l)
 
   lockvar 1 l
   call assert_fails('lua l:add("x")', '[string "vim chunk"]:1: list is locked')
+  call assert_fails('lua l:insert(2)', '[string "vim chunk"]:1: list is locked')
+  call assert_fails('lua l[9] = 1', '[string "vim chunk"]:1: list is locked')
+
+  unlockvar l
+  let l = [1, 2]
+  lua ll = vim.eval('l')
+  let x = luaeval("ll[3]")
+  call assert_equal(v:null, x)
+  call assert_fails('let x = luaeval("ll:xyz(3)")',
+        \ s:lua_53_or_later
+        \ ? "[string \"luaeval\"]:1: attempt to call a nil value (method 'xyz')"
+        \ : "[string \"luaeval\"]:1: attempt to call method 'xyz' (a nil value)")
+  let y = luaeval("ll[{}]")
+  call assert_equal(v:null, y)
 
   lua l = nil
 endfunc
@@ -354,11 +440,7 @@ func Test_lua_list_table()
 endfunc
 
 func Test_lua_list_table_insert_remove()
-  let luaver = split(split(luaeval('_VERSION'), ' ')[1], '\.')
+  if !s:lua_53_or_later
-  let major = str2nr(luaver[0])
-  let minor = str2nr(luaver[1])
-
-  if major < 5 || (major == 5 && minor < 3)
     throw 'Skipped: Lua version < 5.3'
   endif
 
@@ -429,6 +511,7 @@ func Test_lua_dict()
   call assert_match('^dict: \%(0x\)\?\x\+$', luaeval('tostring(d)'))
 
   call assert_equal('abc', luaeval('d[1]'))
+  call assert_equal(v:null, luaeval('d[22]'))
 
   lua d[0] = 124
   lua d[4] = nil
@@ -436,6 +519,23 @@ func Test_lua_dict()
 
   lockvar 1 d
   call assert_fails('lua d[6] = 1', '[string "vim chunk"]:1: dict is locked')
+  unlockvar d
+
+  " Error case
+  lua d = {}
+  lua d[''] = 10
+  call assert_fails("let t = luaeval('vim.dict(d)')",
+        \ '[string "luaeval"]:1: table has empty key')
+  let d = {}
+  lua x = vim.eval('d')
+  call assert_fails("lua x[''] = 10", '[string "vim chunk"]:1: empty key')
+  lua x['a'] = nil
+  call assert_equal({}, d)
+
+  " cannot assign funcrefs in the global scope
+  lua x = vim.eval('g:')
+  call assert_fails("lua x['min'] = vim.funcref('max')",
+        \ '[string "vim chunk"]:1: cannot assign funcref to builtin scope')
 
   lua d = nil
 endfunc
@@ -493,6 +593,28 @@ func Test_lua_blob()
   call assert_fails('lua b:add(true)', '[string "vim chunk"]:1: string expected, got boolean')
   call assert_fails('lua b:add({})', '[string "vim chunk"]:1: string expected, got table')
   lua b = nil
+
+  let b = 0z0102
+  lua lb = vim.eval('b')
+  let n = luaeval('lb[1]')
+  call assert_equal(2, n)
+  let n = luaeval('lb[6]')
+  call assert_equal(v:null, n)
+  call assert_fails('let x = luaeval("lb:xyz(3)")',
+        \ s:lua_53_or_later
+        \ ? "[string \"luaeval\"]:1: attempt to call a nil value (method 'xyz')"
+        \ : "[string \"luaeval\"]:1: attempt to call method 'xyz' (a nil value)")
+  let y = luaeval("lb[{}]")
+  call assert_equal(v:null, y)
+
+  lockvar b
+  call assert_fails('lua lb[1] = 2', '[string "vim chunk"]:1: blob is locked')
+  call assert_fails('lua lb:add("12")', '[string "vim chunk"]:1: blob is locked')
+
+  " Error cases
+  lua t = {}
+  call assert_fails('lua b = vim.blob(t)',
+        \ '[string "vim chunk"]:1: string expected, got table')
 endfunc
 
 func Test_lua_funcref()
@@ -506,6 +628,17 @@ func Test_lua_funcref()
   lua msg = vim.funcref"tr"(msg, "|", " ")
   call assert_equal("funcref test OK", luaeval('msg'))
 
+  " Error cases
+  call assert_fails('lua f1 = vim.funcref("")',
+        \ '[string "vim chunk"]:1: invalid function name: ')
+  call assert_fails('lua f1 = vim.funcref("10")',
+        \ '[string "vim chunk"]:1: invalid function name: 10')
+  let fname = test_null_string()
+  call assert_fails('lua f1 = vim.funcref(fname)',
+        \ "[string \"vim chunk\"]:1: bad argument #1 to 'funcref' (string expected, got nil)")
+  call assert_fails('lua vim.funcref("abc")()',
+        \ '[string "vim chunk"]:1: cannot call funcref')
+
   " dict funcref
   function Mylen() dict
     return len(self.data)
@@ -619,6 +752,10 @@ func Test_luaeval_error()
   \ '[string "luaeval"]:1: attempt to perform arithmetic on a nil value')
   call assert_fails("call luaeval(']')",
   \ "[string \"luaeval\"]:1: unexpected symbol near ']'")
+  lua co = coroutine.create(function () print("hi") end)
+  call assert_fails('let i = luaeval("co")', 'luaeval: cannot convert value')
+  lua co = nil
+  call assert_fails('let m = luaeval("{}")', 'luaeval: cannot convert value')
 endfunc
 
 " Test :luafile foo.lua
@@ -664,6 +801,17 @@ func Test_luafile_error()
   bwipe!
 endfunc
 
+" Test for dealing with strings containing newlines and null character
+func Test_lua_string_with_newline()
+  let x = execute('lua print("Hello\nWorld")')
+  call assert_equal("\nHello\nWorld", x)
+  new
+  lua k = vim.buffer(vim.eval('bufnr()'))
+  lua k:insert("Hello\0World", 0)
+  call assert_equal(["Hello\nWorld", ''], getline(1, '$'))
+  close!
+endfunc
+
 func Test_lua_set_cursor()
   " Check that setting the cursor position works.
   new

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1105,
 /**/
     1104,
 /**/