Fix to `isa-shell-command-to-string' suggested by Jonathan S. Shapiro

1 files changed, 3 insertions, 5 deletions

diff --git a/isa/isabelle-system.el b/isa/isabelle-system.el
index 4ca667a8..363e9424 100644
--- a/isa/isabelle-system.el
+++ b/isa/isabelle-system.el
@@ -86,11 +86,9 @@ with full path."
 
 (defun isa-shell-command-to-string (command)
   "Like shell-command-to-string except the last character is stripped."
-  ;; FIXME: sometimes the command may fail. This will usually cause PG
-  ;; to break.  Bit of an effort to trap errors here, we would need
-  ;; to provide some advice to shell-command-to-string to retain result
-  ;; of call to call-process, and raise and error in case it failed.
-  (substring (shell-command-to-string command) 0 -1))
+  (let ((s (shell-command-to-string command)))
+    (if (equal (length s) 0) s
+      (substring s -1))))
 
 (defun isa-getenv (envvar &optional default)
   "Extract an environment variable setting using the `isatool' program.