Error in apply_guides on diffPrint(df, df, extra = list(row.names = FALSE))

[HenrikBengtsson]

Trying to compare two data.frame:s using print(..., row.names = FALSE) gives an error in some cases (not always - I think it might be related to factors but not sure). Here is a minimal example. With:

> library("diffobj")
> df <- data.frame(x = "A")

this works:

> diffPrint(df, df)
No visible differences between objects.
< df         > df       
@@ 1,2 @@    @@ 1,2 @@  
    x            x      
  1 A          1 A      

> diffPrint(df, df, extra = list(row.names = TRUE))
No visible differences between objects.
< print(d..  > print(d..
@@ 1,2 @@    @@ 1,2 @@  
    x            x      
  1 A          1 A     

but trying to apply extra = list(row.names = FALSE) fails:

> diffPrint(df, df, extra = list(row.names = FALSE))
Error in apply_guides(target, tar.capt, guide_fun) : 
  `guides*` method must produce an integer vector containing unique index values for the `obj.as.chr` vector; If you did not specify a `guides` function or define custom `guides*` methods contact maintainer (see `?guides`).  Proceeding without guides.
In addition: Warning messages:
1: In min(which(!space.rows & seq_along(space.rows) > head.row)) :
  no non-missing arguments to min; returning Inf
2: In max(which(!space.rows)) :
  no non-missing arguments to max; returning -Inf

This is with:

> sessionInfo()
R version 3.4.2 (2017-09-28)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 16.04.3 LTS

Matrix products: default
BLAS: /usr/lib/atlas-base/atlas/libblas.so.3.0
LAPACK: /usr/lib/atlas-base/atlas/liblapack.so.3.0

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
 [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
 [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
 [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] diffobj_0.1.7

loaded via a namespace (and not attached):
[1] compiler_3.4.2 tools_3.4.2    crayon_1.3.4 

PS. Thanks for a brilliant package!

[brodieG]

Thanks for the nice MRE. I can confirm the problem. Recent r-devel changes are causing test failures so I probably will fix this as I fix the failing tests. In the meantime you can use:

diffPrint(df, df, extra = list(row.names =F), guides=FALSE)

although it degrades the usability a little bit. One other option is to provide your own guides function that properly handles the formatting of rowname-less dfs (see ?diffobj::guides, but not for the faint of heart).