Print testcase at the REPL if verbose is TRUE

Author: lionel-

R/testthat-ui.R

@@ -29,6 +29,11 @@
 #' @param verbose If \code{TRUE}, the contents of the SVG files for
 #'   the comparison plots are printed during testthat checks. This is
 #'   useful to investigate errors when testing remotely.
+#'
+#'   Note that it is not possible to print the original SVG during
+#'   interactive use. This is because there is no way of figuring out
+#'   in which directory this SVG lives. Consequently, only the test
+#'   case is printed.
 #' @export
 #' @examples
 #' ver <- gdtools::version_freetype()
@@ -76,6 +81,7 @@ expect_doppelganger <- function(title, fig, path = NULL, ...,
   } else {
     case <- new_case(case)
     maybe_collect_case(case)
+    maybe_print_svgs(case)
     msg <- paste0("Figure not generated yet: ", fig_name, ".svg")
     exp <- expectation_new(msg, case)
   }
@@ -112,6 +118,14 @@ compare_figs <- function(case) {
   exp
 }
 
+# Print only if we're not collecting. The testthat reporter prints
+# verbose cases at a later point.
+maybe_print_svgs <- function(case, pkg_path = NULL) {
+  if (case$verbose && is_null(active_collecter())) {
+    meow(svg_files_lines(case, pkg_path))
+  }
+}
+
 expectation_new <- function(msg, case) {
   exp <- testthat::expectation("skip", msg)
   classes <- c(class(exp), "vdiffr_new")

R/utils.R

@@ -95,13 +95,22 @@ svg_files_lines <- function(case, pkg_path = NULL) {
     original_path <- from_test_dir(pkg_path, case$path)
   }
 
-  chr_lines(
-    glue(
-      ">> Failed doppelganger: { case$name }
-       > Original SVG:"
-    ),
-    readLines(original_path),
-    "",
+  # If called from interactive use, we most likely can't figure out
+  # where the original SVG lives (most likely in a subdirectory within
+  # the `figs` folder) so we don't print it.
+  if (file.exists(original_path)) {
+    original_lines <- chr_lines(
+      "> Original SVG:",
+      readLines(original_path),
+      ""
+    )
+  } else {
+    original_lines <- ""
+  }
+
+  lines <- chr_lines(
+    glue(">> Failed doppelganger: { case$name }"),
+    original_lines,
     "> Testcase SVG:",
     readLines(case$testcase),
     ""