helpful

commit a1b86c21ac421105be96aa2666ec5bec723ce51b
parent 4a508ff1755fce4e1697a215d8b9f2e5ad7bb78b
Author: Wilfred Hughes <me@wilfred.me.uk>
Date:   Sun,  2 Apr 2017 12:17:22 +0100

Handle function not having a docstring.

Diffstat:
M
helpful.el
 | 
10
+++++-----
M
test/unit-test.el
 | 
6
++++++

2 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/helpful.el b/helpful.el
@@ -99,7 +99,8 @@ state of the current symbol."
     (insert
      (format "Symbol: %s\n\n" helpful--sym)
      (helpful--heading "Documentation\n")
-     (helpful--docstring helpful--sym)
+     (or (helpful--docstring helpful--sym)
+         "No docstring.")
      (helpful--heading "\n\nSymbol Properties\n")
      (helpful--format-properties helpful--sym)
      (helpful--heading "\n\nTools\n")
@@ -115,13 +116,12 @@ state of the current symbol."
 
 (defun helpful--docstring (sym)
   "Get the docstring for SYM."
-  (let* ((docstring (documentation sym))
-         (docstring-with-usage (help-split-fundoc docstring sym)))
-    (when docstring-with-usage
+  (-when-let (docstring (documentation sym))
+    (-when-let (docstring-with-usage (help-split-fundoc docstring sym))
       (setq docstring (cdr docstring-with-usage))
       ;; Advice mutates the docstring, see
       ;; `advice--make-docstring'. Undo that.
-      ;; TODO: Only do this if the function is adviced.
+      ;; TODO: Only do this if the function is advised.
       (setq docstring (helpful--skip-advice docstring)))
     docstring))
 
diff --git a/test/unit-test.el b/test/unit-test.el
@@ -31,3 +31,9 @@
     (helpful--docstring #'test-foo-advised)
     "Docstring here too.")))
 
+(defun test-foo-no-docstring ()
+  nil)
+
+(ert-deftest helpful--no-docstring ()
+  "We should not crash on a function without a docstring."
+  (should (null (helpful--docstring #'test-foo-no-docstring))))