[PATCH 5 of 6] py3: flush std streams before/after running user code in heredoctest.py

[Yuya Nishihara]

# HG changeset patch
# User Yuya Nishihara <yuya at tcha.org>
# Date 1539667110 -7200
#      Tue Oct 16 07:18:30 2018 +0200
# Node ID 8190570be13dc584dfab6b8470546c298d6900b6
# Parent  a202f1b4611205a08a6730db63dfead59b69f42b
py3: flush std streams before/after running user code in heredoctest.py

Otherwise, things written to stdout.buffer would be interleaved.

diff --git a/tests/heredoctest.py b/tests/heredoctest.py
--- a/tests/heredoctest.py
+++ b/tests/heredoctest.py
@@ -2,6 +2,10 @@ from __future__ import absolute_import, 
 
 import sys
 
+def flush():
+    sys.stdout.flush()
+    sys.stderr.flush()
+
 globalvars = {}
 lines = sys.stdin.readlines()
 while lines:
@@ -15,6 +19,9 @@ while lines:
             snippet += l[4:]
         c = compile(snippet, '<heredoc>', 'single')
         try:
+            flush()
             exec(c, globalvars)
+            flush()
         except Exception as inst:
+            flush()
             print(repr(inst))