pscl crashes with string variable (#1133)

* pscl crashes with string variable
Fixes #1132

* move into test()

Author: strengejacke

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: parameters
 Title: Processing of Model Parameters
-Version: 0.26.0.15
+Version: 0.26.0.16
 Authors@R:
     c(person(given = "Daniel",
              family = "Lüdecke",

R/format_parameters.R

@@ -425,21 +425,20 @@ format_parameters.parameters_model <- function(model, ...) {
       unlist(preds, use.names = FALSE)
     ))
 
-    # for models from pscl, we have "count_" and "zero_" prefixes, which
-    # we need to add to the "pretty_labels" names, so that we can match
-    # them with the parameters
-    if (inherits(model, c("zeroinfl", "hurdle"))) {
-      pretty_labels <- c(
-        stats::setNames(pretty_labels, paste0("count_", names(pretty_labels))),
-        stats::setNames(pretty_labels, paste0("zero_", names(pretty_labels)))
-      )
-    }
-
     # retrieve pretty names attribute
     pn <- attributes(params)$pretty_names
     # replace former pretty names with labels, if we have any labels
     # (else, default pretty names are returned)
     if (!is.null(pretty_labels)) {
+      # for models from pscl, we have "count_" and "zero_" prefixes, which
+      # we need to add to the "pretty_labels" names, so that we can match
+      # them with the parameters
+      if (inherits(model, c("zeroinfl", "hurdle"))) {
+        pretty_labels <- c(
+          stats::setNames(pretty_labels, paste0("count_", names(pretty_labels))),
+          stats::setNames(pretty_labels, paste0("zero_", names(pretty_labels)))
+        )
+      }
       # check if we have any interactions, and if so, create combined labels
       interactions <- pn[grepl(":", names(pn), fixed = TRUE)]
       if (length(interactions)) {

tests/testthat/test-pretty_names.R

@@ -80,6 +80,13 @@ withr::with_options(
 
       model <- pscl::zeroinfl(art ~ fem + mar, data = mydf)
       expect_snapshot(print(model_parameters(model), pretty_names = "labels", zap_small = TRUE))
+
+      # doesn't crash if pretty-labels is NULL
+      mydf <- pscl::bioChemists
+      mydf$mar <- as.character(mydf$mar)
+      model <- pscl::zeroinfl(art ~ fem + mar, data = mydf)
+      out <- model_parameters(model)
+      expect_identical(dim(out), c(6L, 10L))
     })
   }
 )