Error in model_parameters.aov plot() method? (#376)

* Error in model_parameters.aov plot() method?
Fixes #286

* fix

Author: strengejacke

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: see
 Title: Model Visualisation Toolbox for 'easystats' and 'ggplot2'
-Version: 0.9.0.12
+Version: 0.9.0.13
 Authors@R:
     c(person(given = "Daniel",
              family = "Lüdecke",

NEWS.md

@@ -11,9 +11,12 @@
 - `plot()` for `model_parameters()` gets a `show_direction` argument, to turn
   off the direction of the effect in the plot.
 
+- `plot()` for `model_parameters()` now gives an informative error message when
+  trying to plot Anova tables (which does not work).
+
 - `plot()` for `simulate_parameters()` now better copes with models that have
   multiple response levels (e.g. multinomial models).
-  
+
 - Gains `{patchwork}` as a hard dependency given its importance for the package.
 
 ## Bug fixes

R/plot.parameters_model.R

@@ -65,6 +65,12 @@ plot.see_parameters_model <- function(x,
   # retrieve settings ----------------
   model_attributes <- attributes(x)[!names(attributes(x)) %in% c("names", "row.names", "class")]
 
+  # no plot for anova
+  model_class <- attributes(x)$model_class
+  if (!is.null(model_class) && any(model_class %in% c("aov", "anova"))) {
+    insight::format_error("Plots cannot be created for Anova tables. Please fit a (linear) regression model and try again.") # nolint
+  }
+
   # for GAMs, remove smooth terms
   if (!is.null(x$Component) && any(x$Component == "smooth_terms")) {
     x <- x[x$Component != "smooth_terms", ]

tests/testthat/test-plot.parameters_model.R

@@ -14,6 +14,16 @@ test_that("`plot.see_parameters_model()` works", {
   )
 })
 
+
+test_that("`plot.see_parameters_model()` errors for anova tables", {
+  skip_if_not_installed("parameters")
+  data(iris)
+  m <- aov(Sepal.Length ~ Species, data = iris)
+  mp <- parameters::model_parameters(m)
+  expect_error(plot(mp), regex = "Plots cannot be created")
+})
+
+
 test_that("`plot.see_parameters_model()` random parameters works", {
   skip_if_not_installed("lme4")
   skip_if_not_installed("parameters")