[Libguestfs] [common PATCH] Trim whitespaces from commands read from file

[Richard W.M. Jones]

On Wed, Jan 29, 2020 at 01:12:51PM +0100, Martin Kletzander wrote:
> On Thu, Jan 23, 2020 at 03:16:47PM +0000, Richard W.M. Jones wrote:
> >On Thu, Jan 23, 2020 at 02:04:53PM +0100, Martin Kletzander wrote:
> >>On Thu, Jan 23, 2020 at 12:16:50PM +0100, Martin Kletzander wrote:
> >>>Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
> >>
> >>I forgot to mention this is trying to fix the following BZ:
> >>
> >>https://bugzilla.redhat.com/show_bug.cgi?id=1351000
> >
> >>>---
> >>>mlcustomize/customize_cmdline.ml | 1 +
> >>>1 file changed, 1 insertion(+)
> >>>
> >>>diff --git a/mlcustomize/customize_cmdline.ml b/mlcustomize/customize_cmdline.ml
> >>>index c062379879e2..67e85af2ad93 100644
> >>>--- a/mlcustomize/customize_cmdline.ml
> >>>+++ b/mlcustomize/customize_cmdline.ml
> >>>@@ -481,6 +481,7 @@ let rec argspec () =
> >>>    ] in
> >>>    let lines = read_whole_file filename in
> >>>    let lines = String.lines_split lines in
> >>>+    let lines = List.map String.trim lines in
> >
> >I wonder if String.triml is safer?  However I cannot
> >think of a way that it's likely to be useful to have
> >trailing whitespace be meaningful.
> >
> >Please put this in the subject line of the commit
> >message: “(RHBZ#1351000)”.  This will ensure that it
> >is picked up by the release notes by the
> >bugs-in-changelog script.
> >
> >ACK
> >
> 
> I found that this is still not enough to make it behave in a nice way.  What we
> probably want is the split, which happens few lines lower, to actually behave
> similar to Str.split, which actually splits by any number of the delimiters (so
> that "asdf fdsa" is split into ["asdf"; "fdsa"] and not ["asdf"; ""; "fdsa"].
> 
> I know this fix is not important at all, but since I wanted to exercise some
> OCaml, I will try to fix that implementation instead.
> 
> Do any one of you know of a part of any libguestfs tool which would depend on
> the current, too strict, behaviour?

Almost everything.  You can't change that library function, add a new
one instead.

Rich.

> >Rich.
> >
> >>>    let lines = List.filter (
> >>>      fun line ->
> >>>        String.length line > 0 && line.[0] <> '#'
> >>>--
> >>>2.25.0
> >>>
> >>>_______________________________________________
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> >>>Libguestfs at redhat.com
> >>>https://www.redhat.com/mailman/listinfo/libguestfs
> >
> >
> >
> >-- 
> >Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
> >Read my programming and virtualization blog: http://rwmj.wordpress.com
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-- 
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