Add default arguments to gradethis_equal() (#347)

Co-authored-by: rossellhayes <[email protected]>

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: gradethis
 Title: Automated Feedback for Student Exercises in 'learnr' Tutorials
-Version: 0.2.12.9004
+Version: 0.2.12.9005
 Authors@R: c(
     person("Garrick", "Aden-Buie", , "[email protected]", role = "aut",
            comment = c(ORCID = "0000-0002-7111-0077")),

NEWS.md

@@ -1,3 +1,8 @@
+# gradethis 0.2.12.9005
+
+* `gradethis_equal()` now has default arguments of `x = .result` and `y = .solution` (#347).
+    * `gradethis_equal.default()` now has a default argument of `tolerance = sqrt(.Machine$double.eps)`.
+
 # gradethis 0.2.12.9004
 
 * Add `fail_if_not_equal()` (#346).

R/gradethis_equal.R

@@ -9,15 +9,26 @@
 #' @examples
 #' gradethis_equal(mtcars[mtcars$cyl == 6, ], mtcars[mtcars$cyl == 6, ])
 #' gradethis_equal(mtcars[mtcars$cyl == 6, ], mtcars[mtcars$cyl == 4, ])
-gradethis_equal <- function(x, y, ...) {
+gradethis_equal <- function(x = .result, y = .solution, ...) {
+  if (is_placeholder(x) || is_placeholder(y)) {
+    x <- resolve_placeholder(x)
+    y <- resolve_placeholder(y)
+    return(gradethis_equal(x, y, ...))
+  }
+
   UseMethod("gradethis_equal")
 }
 
 #' @describeIn gradethis_equal
 #'   The default comparison method, which uses [waldo::compare]
 #' @inheritParams waldo::compare
 #' @export
-gradethis_equal.default <- function(x, y, tolerance, ...) {
+gradethis_equal.default <- function(
+  x,
+  y,
+  tolerance = sqrt(.Machine$double.eps),
+  ...
+) {
   local_options_waldo_compare()
 
   tryCatch(