Re: [PATCH] fix POSIX 'command -pv'
Thorsten Glaser schreef op 26-02-16 om 21:57:
> In the end, I decided I don’t like the code and rewrote it entirely,
> separating options processing, simplifying, etc. but thanks anyway!
Yes, that code looks much cleaner. No more opaque mixing of two
different command's option logic.
I also missed something in that patch -- aliases still weren't handled
correctly. But your new code fixes that too.
I also submitted a patch to OpenBSD ksh for this and in the process I
wrote a couple of more robust regression tests, one to make sure
'command' behaves correctly and the other to check 'whence' behaviour
hasn't changed. Here they are as a patch against mksh, latest cvs. (They
pass.)
- M.
cvs diff: Diffing .
Index: check.t
===
RCS file: /cvs/src/bin/mksh/check.t,v
retrieving revision 1.726
diff -u -r1.726 check.t
--- check.t 1 Mar 2016 18:30:25 - 1.726
+++ check.t 5 Mar 2016 03:47:29 -
@@ -12196,13 +12196,75 @@
after 0='swc' 1='二' 2=''
= done
---
-name: command-path
+name: command-pvV-posix-priorities
description:
- Check 'command -p' is not 'whence -p'
-stdin:
- command -pv if
+ For POSIX compatibility, command -v should find aliases and reserved
+ words, and command -p[vV] should find aliases, reserved words, and
+ builtins over external commands.
+stdin:
+ PATH=/bin:/usr/bin
+ alias foo="bar baz"
+ bar() { :; }
+ for word in 'if' 'foo' 'bar' 'set' 'true'; do
+ command -v "$word"
+ command -pv "$word"
+ command -V "$word"
+ command -pV "$word"
+ done
+expected-stdout:
+ if
+ if
+ if is a reserved word
+ if is a reserved word
+ alias foo='bar baz'
+ alias foo='bar baz'
+ foo is an alias for 'bar baz'
+ foo is an alias for 'bar baz'
+ bar
+ bar
+ bar is a function
+ bar is a function
+ set
+ set
+ set is a special shell builtin
+ set is a special shell builtin
+ true
+ true
+ true is a shell builtin
+ true is a shell builtin
+---
+name: whence-preserve-tradition
+description:
+ This regression test is to ensure that the POSIX compatibility
+ changes for 'command' (see previous test) do not affect traditional
+ 'whence' behaviour.
+stdin:
+ PATH=/bin:/usr/bin
+ alias foo="bar baz"
+ bar() { :; }
+ for word in 'if' 'foo' 'bar' 'set' 'true'; do
+ whence "$word"
+ whence -p "$word"
+ whence -v "$word"
+ whence -pv "$word"
+ done
expected-stdout:
if
+ if is a reserved word
+ if not found
+ 'bar baz'
+ foo is an alias for 'bar baz'
+ foo not found
+ bar
+ bar is a function
+ bar not found
+ set
+ set is a special shell builtin
+ set not found
+ true
+ /usr/bin/true
+ true is a shell builtin
+ true is a tracked alias for /usr/bin/true
---
name: duffs-device
description:
Re: [PATCH] fix POSIX 'command -pv'
Martijn Dekker dixit: >I found another minor POSIX bug in mksh 'command': the options -p and -v >don't combine correctly. Thanks. Sorry it took me some time to have a look at this, but I like to… put off dealing with standards… ☺ In the end, I decided I don’t like the code and rewrote it entirely, separating options processing, simplifying, etc. but thanks anyway! bye, //mirabilos -- FWIW, I'm quite impressed with mksh interactively. I thought it was much *much* more bare bones. But it turns out it beats the living hell out of ksh93 in that respect. I'd even consider it for my daily use if I hadn't wasted half my life on my zsh setup. :-) -- Frank Terbeck in #!/bin/mksh
[PATCH] fix POSIX 'command -pv'
I found another minor POSIX bug in mksh 'command': the options -p and -v
don't combine correctly.
The -p flag means that 'command' will search the system default PATH
instead of the current PATH, but does not change that builtins take
precedence over external commands. Hence 'command -p test' will execute
the 'test' builtin and not /bin/test.
'-v' output should reflect what would actually be executed without that
flag. Without the -p flag, this works fine:
$ command -v true
true
However, command -pv always shows the external command, even if command
-p does not execute it:
$ command -pv [
/bin/[
(expected output: '[')
$ command -p [
mksh: [: missing ]
it's the builtin, as expected
This also means that 'command -pv' should find shell keywords such as
'if' the same way 'command -v' should (as is the behaviour on ksh93,
bash, dash, etc.), so my earlier patch for 'command' of 1 July also
needs to be amended.
$ command -pv if
(nothing, expected output: if)
I believe the following patch fixes it (without affecting 'whence -p').
Thanks,
- M.
diff -ur mksh.orig/funcs.c mksh/funcs.c
--- mksh.orig/funcs.c 2016-01-20 22:34:37.0 +0100
+++ mksh/funcs.c2016-02-14 23:27:54.0 +0100
@@ -548,15 +548,14 @@
* or whence -pv. This should be considered a feature.
*/
vflag = Vflag;
- }
- if (pflag)
+ } else if (pflag)
fcflags &= ~(FC_BI | FC_FUNC);
while ((vflag || rv == 0) && (id = *wp++) != NULL) {
uint32_t h = 0;
tp = NULL;
- if (!pflag)
+ if (!iam_whence || !pflag)
tp = ktsearch(, id, h = hash(id));
if (!tp && !pflag) {
tp = ktsearch(, id, h ? h : hash(id));
