master f4ea159 2/2: ert: Add basic explainer for string-equal

[Stefan Kangas]

branch: master
commit f4ea15907aeb020b80d021a8d6bf212bcde08ab9
Author: Stefan Kangas <stefan@marxist.se>
Commit: Stefan Kangas <stefan@marxist.se>

    ert: Add basic explainer for string-equal
    
    * lisp/emacs-lisp/ert.el (ert--explain-string-equal): Add basic
    explainer for 'string-equal' based on 'ert--explain-equal'.
---
 lisp/emacs-lisp/ert.el | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lisp/emacs-lisp/ert.el b/lisp/emacs-lisp/ert.el
index 6d867ab..e72321f 100644
--- a/lisp/emacs-lisp/ert.el
+++ b/lisp/emacs-lisp/ert.el
@@ -540,6 +540,14 @@ Returns nil if they are."
     (ert--explain-equal-rec a b)))
 (put 'equal 'ert-explainer 'ert--explain-equal)
 
+(defun ert--explain-string-equal (a b)
+  "Explainer function for `string-equal'."
+  ;; Convert if they are symbols.
+  (let ((as (if (symbolp a) (symbol-name a) a))
+        (bs (if (symbolp b) (symbol-name b) b)))
+    (ert--explain-equal-rec as bs)))
+(put 'string-equal 'ert-explainer 'ert--explain-string-equal)
+
 (defun ert--significant-plist-keys (plist)
   "Return the keys of PLIST that have non-null values, in order."
   (cl-assert (zerop (mod (length plist) 2)) t)