semPaths(..., nCharNodes = 0) does not give labels in a named vector, causing an error when calling set_cfa_layout() after change_node_label()

[marklhc]

As illustrated below, semPaths() gives a named vector for the labels without specifying nCharNodes, but gives an unnamed vector when nCharNodes = 0.

library(lavaan)
#> This is lavaan 0.6-7
#> lavaan is BETA software! Please report any bugs.
library(semPlot)
#> Registered S3 methods overwritten by 'huge':
#>   method    from   
#>   plot.sim  BDgraph
#>   print.sim BDgraph
library(semptools)

mod_pa <- 
  'x1 ~~ x2
   x3 ~  x1 + x2
   x4 ~  x1 + x3
  '
fit_pa <- lavaan::sem(mod_pa, pa_example)
# Use custom labels
m <- matrix(c("x1",   NA,  NA,   NA,
              NA, "x3",  NA, "x4",
              "x2",   NA,  NA,   NA), byrow = TRUE, 3, 4)
p_pa <- semPaths(fit_pa, whatLabels = "est",
                 sizeMan = 10,
                 edge.label.cex = 1.15,
                 layout = m)

p_pa$graphAttributes$Nodes$labels
#>   x3   x4   x1   x2 
#> "x3" "x4" "x1" "x2"

p_pa2 <- semPaths(fit_pa,
  whatLabels = "est",
  nCharNodes = 0, 
  sizeMan = 10,
  edge.label.cex = 1.15,
  layout = m
)

p_pa2$graphAttributes$Nodes$labels
#> [1] "x3" "x4" "x1" "x2"

^{Created on 2020-12-31 by the reprex package (v0.3.0)}

This causes an issue as when the labels are not named, the labels after applying change_node_labels() will also be unnamed, and the original variable names are lost, causing set_cfa_layout() and set_sem_layout() to fail.

A solution is to modify change_node_labels() to add the original labels as names when the original labels is an unnamed vector. I've made the changes and will push to a new branch before merging.

[sfcheung]

I checked and this problem should have been fixed in. See test-change-node.R and bfc4ab6.