Misleading names using pretty_names in combination with cut() (#945)

* Misleading names using `pretty_names` in combination with `cut()`
Fixes #943

* add test

R/format_parameters.R

@@ -319,11 +319,11 @@ format_parameters.parameters_model <- function(model, ...) {
   if (all(grepl(pattern_cut_right, level))) {
     lower_bounds <- gsub(pattern_cut_right, "\\1", level)
     upper_bounds <- gsub(pattern_cut_right, "\\2", level)
-    level <- paste0(as.numeric(lower_bounds) + 1, "-", upper_bounds)
+    level <- paste0(">", as.numeric(lower_bounds), "-", upper_bounds)
   } else if (all(grepl(pattern_cut_left, level))) {
     lower_bounds <- gsub(pattern_cut_left, "\\1", level)
     upper_bounds <- gsub(pattern_cut_left, "\\2", level)
-    level <- paste0(lower_bounds, "-", as.numeric(upper_bounds) - 1)
+    level <- paste0(lower_bounds, "-<", as.numeric(upper_bounds))
   }
   paste0(variable, " ", brackets[1], level, brackets[2])
 }

tests/testthat/test-format_parameters.R

@@ -381,5 +381,20 @@ withr::with_options(
         "e42dep [2] * c12hour"
       )
     })
+
+    test_that("format_parameters, cut", {
+      data(mtcars)
+      mtcars$grp <- cut(mtcars$mpg, breaks = c(0, 15, 20, 50))
+      out <- model_parameters(lm(wt ~ grp, data = mtcars))
+      expect_equal(
+        attributes(out)$pretty_names,
+        c(
+          `(Intercept)` = "(Intercept)", `grp(15,20]` = "grp [>15-20]",
+          `grp(20,50]` = "grp [>20-50]"
+        ),
+        ignore_attr = TRUE
+      )
+      expect_identical(out$Parameter, c("(Intercept)", "grp(15,20]", "grp(20,50]"))
+    })
   }
 )