Fix function aliases of primitive functions

Fixes #159

3 files changed, 17 insertions, 4 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 95c30cf..e6830fa 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,9 @@ narrowed.
 
 Navigation keybindings now work in callee list buffers.
 
+Fixed an issue where we didn't show function aliases as aliases when
+they pointed to a primitive function.
+
 # v0.13
 
 Buffer-local variables are now highlighted, and it's possible to see
diff --git a/helpful.el b/helpful.el
index d4c5611..2ecc9ab 100644
--- a/helpful.el
+++ b/helpful.el
@@ -200,10 +200,17 @@ press \\[keyboard-quit] to gracefully stop the printing."
 Return SYM otherwise."
   (let ((depth 0))
     (if (and (symbolp sym) callable-p)
-        (while (and (symbolp (symbol-function sym))
-                    (< depth 10))
-          (setq sym (symbol-function sym))
-          (setq depth (1+ depth)))
+        (progn
+          ;; Follow the chain of symbols until we find a symbol that
+          ;; isn't pointing to a symbol.
+          (while (and (symbolp (symbol-function sym))
+                      (< depth 10))
+            (setq sym (symbol-function sym))
+            (setq depth (1+ depth)))
+          ;; If this is an alias to a primitive, return the
+          ;; primitive's symbol.
+          (when (subrp (symbol-function sym))
+            (setq sym (intern (subr-name (symbol-function sym))))))
       (setq sym (indirect-variable sym))))
   sym)
 
diff --git a/test/helpful-unit-test.el b/test/helpful-unit-test.el
index d04acca..60d024e 100644
--- a/test/helpful-unit-test.el
+++ b/test/helpful-unit-test.el
@@ -416,6 +416,9 @@ and that buffer has been killed, handle it gracefully."
    (eq (helpful--canonical-symbol 'not t)
        'null))
   (should
+   (eq (helpful--canonical-symbol 'search-forward-regexp t)
+       're-search-forward))
+  (should
    (eq (helpful--canonical-symbol 'emacs-bzr-version nil)
        'emacs-repository-version)))