built-in commands give no syntax error on trailing garbage

[idallen]

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64' 
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-pc-linux-gnu' 
-DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL 
-DHAVE_CONFIG_H   -I.  -I../. -I.././include -I.././lib  -Wdate-time 
-D_FORTIFY_SOURCE=2 -g -O2 -fstack-protector-strong -Wformat 
-Werror=format-security -Wall
uname output: Linux idallen-oak 4.4.0-36-generic #55-Ubuntu SMP Thu Aug 11 
18:01:55 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-pc-linux-gnu

Bash Version: 4.3
Patch Level: 46
Release Status: release

Description:
        Many built-in commands ignore trailing garbage instead of giving
        a syntax error, and this leads newbies into making dumb mistakes
        that they think work fine because of no error message, e.g.:

        $ umask 0777 myfile       # should have been chmod
        $ cd /usr /bin            # goes to /usr not to intended /usr/bin

        Commands should never ignore user input.  If it's there, someone
        thinks it should be used.  Use it or please give error messages.

Repeat-By:
        $ cd /bin this trailing garbage is ignored but should give an error

        $ pushd /bin this trailing garbage is ignored but should give an error

        $ umask 022 this trailing garbage is ignored but should give an error

        $ help help this trailing garbage is ignored but should give an error

        etc.

Fix:
        Make built-in commands give error messages if given too many arguments.