From 05a437b1ad76e50147decd3a9eb3ac77d9bad44f Mon Sep 17 00:00:00 2001
From: Takafumi Arakaki <aka.tkf@gmail.com>
Date: Sun, 3 Jun 2012 17:50:13 +0200
Subject: [PATCH] Make ein:pytools-jump-to-source-command more robust

---
 ein-pytools.el | 24 +++++++++++++++---------
 ein.py         |  8 +++++---
 2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/ein-pytools.el b/ein-pytools.el
index 9faee4b..69c349a 100644
--- a/ein-pytools.el
+++ b/ein-pytools.el
@@ -54,19 +54,25 @@
    kernel
    (format "__import__('ein').find_source('%s')" object)
    (lambda (string object)
-     (let* ((filename-lineno (split-string string "\n"))
-            (filename (car filename-lineno))
-            (lineno (string-to-number (cadr filename-lineno))))
-       (unless (equal filename "")
-         (find-file-other-window filename)
-         (goto-char (point-min))
-         (forward-line (1- lineno))
-         (ein:log 'info "Jumping to the source of %s...Done" object))))
+     (if (string-match "^WARNING: .*" string)
+         (ein:log 'info "Jumping to the source of %s...Not found" object)
+       (let* ((filename-lineno (split-string string "\n"))
+                (filename (car filename-lineno))
+                (lineno (string-to-number (cadr filename-lineno))))
+           (unless (equal filename "")
+             (find-file-other-window filename)
+             (goto-char (point-min))
+             (forward-line (1- lineno))
+             (ein:log 'info "Jumping to the source of %s...Done" object)))))
    (list object)))
 
 (defun ein:pytools-jump-to-source-command ()
   (interactive)
-  (ein:pytools-jump-to-source (ein:pytools-get-kernel) (ein:object-at-point)))
+  (let ((kernel (ein:pytools-get-kernel))
+        (object (ein:object-at-point)))
+    (assert (ein:kernel-ready-p kernel) nil "Kernel is not ready.")
+    (assert object nil "Object at point not found.")
+    (ein:pytools-jump-to-source kernel object)))
 
 (provide 'ein-pytools)
 
diff --git a/ein.py b/ein.py
index 7e24e6d..2e81bcf 100644
--- a/ein.py
+++ b/ein.py
@@ -25,6 +25,8 @@ def find_source(name):
     """Given an object as string, `name`, print its place in source code."""
     from IPython.core.interactiveshell import InteractiveShell
     inst = InteractiveShell.instance()
-    (filename, lineno, use_temp) = inst._find_edit_target(name, {}, [])
-    print filename
-    print lineno
+    ret = inst._find_edit_target(name, {}, [])
+    if ret:
+        (filename, lineno, use_temp) = ret
+        print filename
+        print lineno