R devel - Oct 2013 - unloadNamespace, getPackageName and "Created a package name xxx " warning

Dear all,

Consider this code:
>library("data.table")
>unloadNamespace('data.table')
It produces some warnings
Warning in FUN(X[[1L]], ...) :
  Created a package name, ‘2013-10-29 17:05:51’, when none found
Warning in FUN(X[[1L]], ...) :
  Created a package name, ‘2013-10-29 17:05:51’, when none found
...

The warning is produced by the getPackageName() function.
e.g.
getPackageName(parent.env(getNamespace('data.table')))

I was wondering what could be done to get rid of these warnings, which I
believe in the case "unloadNamespace" case are irrelevant.

The stack of calls is:
# where 3: sapply(where, getPackageName)
# where 4: findClass(what, classWhere)
# where 5: .removeSuperclassBackRefs(cl, cldef, searchWhere)
# where 6: methods:::cacheMetaData(ns, FALSE, ns)
# where 7: unloadNamespace(pkgname)

So for instance:
>findClass('data.frame', getNamespace('data.table'))
generates a warning which once again seems irrelevant.

On the top of my head, I could imagine adding an extra argument to
getPackageName, say warning = TRUE, which would be set to FALSE in the
getPackageName call in findClass() body.

I also wonder if in the case of import namespaces, getPackageName() could
not find a more appropriate name:
>parent.env(getNamespace('data.table'))
<environment: 0x7f6ce4d04040>
attr(,"name")
[1] "imports:data.table"

This namespace has a name that might be used to generate the package name.

My question is: what should be done ?

Thanks for your attention.

Karl Forner

	[[alternative HTML version deleted]]

This was previously reported and fixed.  See the NEWS file and bug 
report 15481.

On 10/29/13 9:19 AM, Karl Forner wrote:
> Dear all,
>
> Consider this code:
>> library("data.table")
>> unloadNamespace('data.table')
>
> It produces some warnings
> Warning in FUN(X[[1L]], ...) :
>    Created a package name, ?2013-10-29 17:05:51?, when none found
> Warning in FUN(X[[1L]], ...) :
>    Created a package name, ?2013-10-29 17:05:51?, when none found
> ...
>
> The warning is produced by the getPackageName() function.
> e.g.
> getPackageName(parent.env(getNamespace('data.table')))
>
> I was wondering what could be done to get rid of these warnings, which I
> believe in the case "unloadNamespace" case are irrelevant.
>
> The stack of calls is:
> # where 3: sapply(where, getPackageName)
> # where 4: findClass(what, classWhere)
> # where 5: .removeSuperclassBackRefs(cl, cldef, searchWhere)
> # where 6: methods:::cacheMetaData(ns, FALSE, ns)
> # where 7: unloadNamespace(pkgname)
>
> So for instance:
>> findClass('data.frame', getNamespace('data.table'))
> generates a warning which once again seems irrelevant.
>
> On the top of my head, I could imagine adding an extra argument to
> getPackageName, say warning = TRUE, which would be set to FALSE in the
> getPackageName call in findClass() body.
>
> I also wonder if in the case of import namespaces, getPackageName() could
> not find a more appropriate name:
>> parent.env(getNamespace('data.table'))
> <environment: 0x7f6ce4d04040>
> attr(,"name")
> [1] "imports:data.table"
>
> This namespace has a name that might be used to generate the package name.
>
> My question is: what should be done ?
>
> Thanks for your attention.
>
> Karl Forner
>
> 	[[alternative HTML version deleted]]
>
>
>
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