Investigate checkUsage() output on internal functions

[joshuaulrich]

@harvey131 discovered an unused environment variable in .rbind.xts() in #313. So it would be a good idea to check for similar issues in all other unexported functions. That will avoid similar confusion in the future.

Here's some code that lists the output of codetools::checkUsage() on the xts namespace.

xtsNamespace <- asNamespace("xts")
xtsNsNames <- ls(xtsNamespace, all = TRUE)
xtsNsObj <- setNames(lapply(xtsNsNames, get, xtsNamespace), xtsNsNames)
xtsNsFunc <- xtsNsObj[sapply(xtsNsObj, is.function)]
checkFunc <- function(fbody, fname) {
  capture.output(codetools::checkUsage(fbody, fname))
}
out <- Map(checkFunc, xtsNsFunc, names(xtsNsFunc))
toCheck <- out[sapply(out, length) > 0]

And here's the output.

R> toCheck
$.rbind.xts
[1] ".rbind.xts: local variable 'env' assigned but may not be used"

$`[<-.xts`
[1] "[<-.xts: local variable '.Class' assigned but may not be used"

$addEventLines
[1] "addEventLines : <anonymous>: local variable 'ta.x' assigned but may not be used"
[2] "addEventLines: local variable 'ind' assigned but may not be used"               

$addLegend
[1] "addLegend: local variable 'ind' assigned but may not be used"

$addPolygon
[1] "addPolygon : <anonymous>: local variable 'ta.x' assigned but may not be used"

$as.fts.xts
[1] "as.fts.xts: local variable 'fts' assigned but may not be used"

$as.timeSeries.xts
[1] "as.timeSeries.xts: local variable 'timeSeries' assigned but may not be used"

$merge.xts
[1] "merge.xts: local variable 'sfx' assigned but may not be used"

$new.replot_xts
[1] "new.replot_xts: local variable 'get_pad' assigned but may not be used"   
[2] "new.replot_xts: local variable 'move_frame' assigned but may not be used"

$re.fts
[1] "re.fts: local variable 'fts' assigned but may not be used"

$re.irts
[1] "re.irts: local variable 'irts' assigned but may not be used"

$re.timeSeries
[1] "re.timeSeries: local variable 'timeSeries' assigned but may not be used"

$re.ts
[1] "re.ts: local variable 'dn' assigned but may not be used"

$re.ts2
[1] "re.ts2 : na.replace: local variable 'ncols' assigned but may not be used"
[2] "re.ts2: local variable 'na.replace' assigned but may not be used"        

$rollcov.xts
[1] "rollcov.xts: local variable 'n1' assigned but may not be used"

$rollmax.xts
[1] "rollmax.xts: local variable 'n1' assigned but may not be used"

$rollmin.xts
[1] "rollmin.xts: local variable 'n1' assigned but may not be used"

$rollsum.xts
[1] "rollsum.xts: local variable 'n1' assigned but may not be used"

$`tzone<-.default`
[1] "tzone<-.default: local variable 'tzone' assigned but may not be used"

It looks like some of those may be bugs... so we should discuss here, and then open issues for the ones that are actually bugs and not false positives.

[harvey131]

• I saw the "n1" in the roll functions so those seem to be used.
• The "sfx" in merge.xts seems like it can be removed.
• Also separately relating to merge.xts, cbind.xts could be cleaned up to remove commented code since it now calls merge.xts.