Merge pull request #759 from r-tmap/758-v4-fails-with-non-standard-co…

…lumn-names

Add test for #758

tests/testing_column_names_v4.Rmd

@@ -0,0 +1,39 @@
+---
+title: "Testing - Column Names"
+author: "Robin Lovelace"
+date: "`r Sys.Date()`"
+output: html_document
+editor_options: 
+  chunk_output_type: console
+---
+
+```{r setup, include=FALSE}
+knitr::opts_chunk$set(echo = TRUE, fig.width = 9)
+```
+
+# Instructions
+
+Open the tmap repository as RStudio project.
+Set Knit Directory (via drop-down menu of the Knit button in RStudio) to Project Directory.
+
+```{r echo=FALSE,message=FALSE,fig.height = 2}
+library(devtools)
+load_all()
+data(World,metro,land)
+
+World$`Unusual column name` = World$HPI
+
+# Test in v4 (2023-08-4):
+tm_shape(World) +
+	tm_polygons("Unusual column name")
+# Error: Visual values used for the variable, "fill" of layer function "tm_polygons" are incorrect.
+
+# Test in v3: works!
+remotes::install_version("tmap", version = "3.3")
+detach("package:tmap", unload = TRUE)
+library(tmap)
+
+World$`Unusual column name` = World$HPI
+tm_shape(World) +
+	tm_polygons("Unusual column name")
+```