#17442: Add chained traceback support to InteractiveInterpreter.

Patch by Claudiu Popa.

1 files changed, 22 insertions, 12 deletions

diff --git a/Lib/code.py b/Lib/code.py
index 6186e04140..86e1f03260 100644
--- a/Lib/code.py
+++ b/Lib/code.py
@@ -137,25 +137,35 @@ class InteractiveInterpreter:
         The output is written by self.write(), below.
 
         """
+        sys.last_type, sys.last_value, last_tb = ei = sys.exc_info()
+        sys.last_traceback = last_tb
         try:
-            type, value, tb = sys.exc_info()
-            sys.last_type = type
-            sys.last_value = value
-            sys.last_traceback = tb
-            tblist = traceback.extract_tb(tb)
-            del tblist[:1]
-            lines = traceback.format_list(tblist)
-            if lines:
-                lines.insert(0, "Traceback (most recent call last):\n")
-            lines.extend(traceback.format_exception_only(type, value))
+            lines = []
+            for value, tb in traceback._iter_chain(*ei[1:]):
+                if isinstance(value, str):
+                    lines.append(value)
+                    lines.append('\n')
+                    continue
+                if tb:
+                    tblist = traceback.extract_tb(tb)
+                    if tb is last_tb:
+                        # The last traceback includes the frame we
+                        # exec'd in
+                        del tblist[:1]
+                    tblines = traceback.format_list(tblist)
+                    if tblines:
+                        lines.append("Traceback (most recent call last):\n")
+                        lines.extend(tblines)
+                lines.extend(traceback.format_exception_only(type(value),
+                                                             value))
         finally:
-            tblist = tb = None
+            tblist = last_tb = ei = None
         if sys.excepthook is sys.__excepthook__:
             self.write(''.join(lines))
         else:
             # If someone has set sys.excepthook, we let that take precedence
             # over self.write
-            sys.excepthook(type, value, tb)
+            sys.excepthook(type, value, last_tb)
 
     def write(self, data):
         """Write a string.