executor: Fix some memory leaks

src/nvim/viml/executor/executor.c

@@ -182,8 +182,14 @@ static int nlua_exec_luado_string(lua_State *const lstate) FUNC_ATTR_NONNULL_ALL
 
   if (luaL_loadbuffer(lstate, lcmd, lcmd_len, NLUA_EVAL_NAME)) {
     nlua_error(lstate, _("E5109: Error while creating lua chunk: %.*s"));
+    if (lcmd_len >= IOSIZE) {
+      xfree(lcmd);
+    }
     return 0;
   }
+  if (lcmd_len >= IOSIZE) {
+    xfree(lcmd);
+  }
   if (lua_pcall(lstate, 0, 1, 0)) {
     nlua_error(lstate, _("E5110: Error while creating lua function: %.*s"));
     return 0;

test/functional/lua/commands_spec.lua

@@ -62,6 +62,15 @@ describe(':lua command', function()
     eq(NIL, funcs.luaeval('lvar'))
     eq(42, funcs.luaeval('gvar'))
   end)
+  it('works with long strings', function()
+    local s = ('x'):rep(100500)
+
+    eq('\nE5104: Error while creating lua chunk: [string "<VimL compiled string>"]:1: unfinished string near \'<eof>\'', redir_exec(('lua vim.api.nvim_buf_set_lines(1, 1, 2, false, {"%s})'):format(s)))
+    eq({''}, curbufmeths.get_lines(0, -1, false))
+
+    eq('', redir_exec(('lua vim.api.nvim_buf_set_lines(1, 1, 2, false, {"%s"})'):format(s)))
+    eq({'', s}, curbufmeths.get_lines(0, -1, false))
+  end)
 end)
 
 describe(':luado command', function()
@@ -104,6 +113,10 @@ describe(':luado command', function()
   end)
   it('works with long strings', function()
     local s = ('x'):rep(100500)
+
+    eq('\nE5109: Error while creating lua chunk: [string "<VimL compiled string>"]:1: unfinished string near \'<eof>\'', redir_exec(('luado return "%s'):format(s)))
+    eq({''}, curbufmeths.get_lines(0, -1, false))
+
     eq('', redir_exec(('luado return "%s"'):format(s)))
     eq({s}, curbufmeths.get_lines(0, -1, false))
   end)

test/functional/lua/luaeval_spec.lua

@@ -243,10 +243,11 @@ describe('luaeval()', function()
        exc_exec([[call luaeval("error('ERROR')")]]))
   end)
 
-  it('does not leak memory when called with too long line with syntax error',
+  it('does not leak memory when called with too long line',
   function()
     local s = ('x'):rep(65536)
     eq('Vim(call):E5107: Error while creating lua chunk for luaeval(): [string "<VimL compiled string>"]:1: unexpected symbol near \')\'',
        exc_exec([[call luaeval("(']] .. s ..[[' + )")]]))
+    eq(s, funcs.luaeval('"' .. s .. '"'))
   end)
 end)