R devel - Mar 2009 - installed.packages and package info cache buglet (PR#13592)

Looks like there is a buglet in 'installed.packages', around line 17:

    for (lib in lib.loc) {
        dest <- file.path(tempdir(), paste("libloc_",
URLencode(lib,=20
            TRUE), paste(fields, collapse =3D ","), ".rds",
sep =3D ""))
        if (!noCache && file.exists(dest) &&
file.info(dest)$mtime >=20
            file.info(lib.loc)$mtime) {

                      ^^^^^^^
                     =20
The 'lib.loc' should be 'lib', otherwise the comparison is
always against the first library in 'lib.loc', not against the one being
checked. [Normally the multiple test in '>' would flag a warning from
'if', but the &&s mean that only the first element is used.]

I can't provide a reproducible example for this, because it's so
installation-dependent.

Still present in R-devel from 8th March.

Mark Bravington
CSIRO
Hobart
Australia

--please do not edit the information below--

Version:
 platform =3D i386-pc-mingw32
 arch =3D i386
 os =3D mingw32
 system =3D i386, mingw32
 status =3D Patched
 major =3D 2
 minor =3D 8.1
 year =3D 2009
 month =3D 02
 day =3D 12
 svn rev =3D 47919
 language =3D R
 version.string =3D R version 2.8.1 Patched (2009-02-12 r47919)

Windows XP (build 2600) Service Pack 2

Locale:
LC_COLLATE=3DEnglish_Australia.1252;LC_CTYPE=3DEnglish_Australia.1252;LC_MONETARY=3DEnglish_Australia.1252;LC_NUMERIC=3DC;LC_TIME=3DEnglish_Australia.1252

Search Path:
 .GlobalEnv, package:grDevices, package:ad, package:chstuff, package:handy2,
package:tweedie, package:statmod, package:handy, package:debug,
package:mvbutils, mvb.session.info, package:tools, package:tcltk, package:boot,
package:stats, package:graphics, package:utils, package:methods, Autoloads,
package:base

>>>>> Mark Bravington <Mark.Bravington at csiro.au>
>>>>>     on Thu, 12 Mar 2009 21:45:18 +0100 (CET) writes:
>> Looks like there is a buglet in 'installed.packages', around
line 17:
>> 
>>     for (lib in lib.loc) {
>>         dest <- file.path(tempdir(), paste("libloc_",
URLencode(lib,=20
>>             TRUE), paste(fields, collapse =3D ","),
".rds", sep =3D ""))
>>         if (!noCache && file.exists(dest) &&
file.info(dest)$mtime >=20
>>             file.info(lib.loc)$mtime) {
>> 
>>                       ^^^^^^^
>>                      =20
>> The 'lib.loc' should be 'lib', otherwise the comparison
is always against t>> he first library in 'lib.loc', not against
the one being checked. [Normally>>  the multiple test in '>'
would flag a warning from 'if', but the &&s mean >> that
only the first element is used.]
>> 
>> I can't provide a reproducible example for this, because it's
so installati>> on-dependent.
>> 
>> Still present in R-devel from 8th March.
and today.  Thank you, Mark,  I've corrected it (in R-devel
only).

Martin Maechler, ETH Zurich

>> Mark Bravington
>> CSIRO
>> Hobart
>> Australia