busybox/shell/ash_test
Denys Vlasenko 9abf53beb4 ash: eval: Variable assignments on functions are no longer persistent
Upstream commit:

    Date: Wed, 4 Apr 2018 17:54:01 +0800
    eval: Variable assignments on functions are no longer persistent

    Dirk Fieldhouse <fieldhouse@gmx.net> wrote:
    > In POSIX.1-2017 ("simultaneously IEEE Std 1003.1™-2017 and The Open
    > Group Technical Standard Base Specifications, Issue 7")
    > <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09>,
    > we read under '2.9.1 Simple Commands'
    >
    > "Variable assignments shall be performed as follows:
    > ...
    > -    If the command name is a standard utility implemented as a function
    > (see XBD Utility), the effect of variable assignments shall be as if the
    > utility was not implemented as a function.
    > ...
    > -    If the command name is a function that is not a standard utility
    > implemented as a function, variable assignments shall affect the current
    > execution environment during the execution of the function. It is
    > unspecified:
    >
    >     *   Whether or not the variable assignments persist after the
    > completion of the function
    >
    >     *   Whether or not the variables gain the export attribute during
    > the execution of the function
    >
    >     *   Whether or not export attributes gained as a result of the
    > variable assignments persist after the completion of the function (if
    > variable assignments persist after the completion of the function)"

    POSIX used to require the current dash behaviour.  However, you're
    right that this is no longer the case.

    This patch will remove the persistence of the variable assignment.

    I have considered the exporting the variables during the function
    execution but have decided against it because:

    1) It makes the code bigger.
    2) dash has never done this in the past.
    3) You cannot use this portably anyway.

    Reported-by: Dirk Fieldhouse <fieldhouse@gmx.net>
    Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

function                                             old     new   delta
evalcommand                                         1606    1635     +29
evalcase                                             313     317      +4
evalfun                                              280     268     -12
pushlocalvars                                         48       -     -48
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 2/1 up/down: 33/-60)            Total: -27 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-08-05 11:14:11 +02:00
..
ash-alias
ash-arith ash: parser: Add syntax stack for recursive parsing 2018-04-02 13:15:37 +02:00
ash-getopts hush: fix "getopts" builtin to not be upset by other builtins calling getopt() 2017-08-29 13:38:30 +02:00
ash-glob hush: never glob result of dquoted "${v:+/bin/c*}" 2018-07-20 19:29:41 +02:00
ash-heredoc hush: add "heredoc.tests" from ash, tweak ash "is a function" message 2018-07-24 17:10:18 +02:00
ash-invert
ash-misc ash: eval: Variable assignments on functions are no longer persistent 2018-08-05 11:14:11 +02:00
ash-parsing hush: fix recent breakage from parse_stream() changes 2018-04-11 20:00:43 +02:00
ash-psubst ash: add LINENO support 2018-01-27 22:02:05 +01:00
ash-quoting hush: fix handling of '' in ${var:+ARG} 2018-07-20 17:36:06 +02:00
ash-read shell: optional support for read -t N.NNN, closes 10101 2017-07-20 16:09:31 +02:00
ash-redir hush: fix nested redirects colliding with script fds 2018-07-24 16:54:41 +02:00
ash-signals ash: copy three tests from hush_test/hush-signals/* 2017-07-24 19:42:46 +02:00
ash-standalone ash: fix nofork bug where environment is not properly passed to a command 2017-11-03 14:16:25 +01:00
ash-vars ash: eval: Variable assignments on functions are no longer persistent 2018-08-05 11:14:11 +02:00
ash-z_slow hush: improve ${var#...}, ${var:+...} and ${var/.../...} - handle quoting 2018-07-17 14:21:38 +02:00
.gitignore ash_test: ignore generated files 2016-03-22 18:15:24 -04:00
printenv.c do not use `a' quoting style in comments 2017-08-02 14:26:33 +02:00
recho.c whitespace cleanup 2010-10-29 11:46:52 +02:00
run-all ash: add all hush parsing tests to ast tests 2017-07-24 02:49:56 +02:00
zecho.c whitespace cleanup 2010-10-29 11:46:52 +02:00