Close scons logfiles on completion

Files written to in logging operations could remain unclosed: more
modern Pythons grumble about this; given the type of Python build,
could emit ResourceWarning messages which cause tests to fail.
Close by registering calls with atexit.

Affects Trace, cache debug, taskmastertrace, configure.

Signed-off-by: Mats Wichmann <mats@linux.com>

1 files changed, 26 insertions, 8 deletions

diff --git a/SCons/Debug.py b/SCons/Debug.py
index 706b4c4..10cd2f5 100644
--- a/SCons/Debug.py
+++ b/SCons/Debug.py
@@ -33,6 +33,7 @@ caller_trace()
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
+import atexit
 import os
 import sys
 import time
@@ -66,7 +67,7 @@ def string_to_classes(s):
 def fetchLoggedInstances(classes="*"):
     classnames = string_to_classes(classes)
     return [(cn, len(tracked_classes[cn])) for cn in classnames]
-  
+
 def countLoggedInstances(classes, file=sys.stdout):
     for classname in string_to_classes(classes):
         file.write("%s: %d\n" % (classname, len(tracked_classes[classname])))
@@ -201,22 +202,39 @@ if sys.platform == 'win32':
     TraceDefault = 'con'
 else:
     TraceDefault = '/dev/tty'
-
-TimeStampDefault = None
+TimeStampDefault = False
 StartTime = time.time()
 PreviousTime = StartTime
 
-def Trace(msg, file=None, mode='w', tstamp=None):
-    """Write a trace message to a file.  Whenever a file is specified,
-    it becomes the default for the next call to Trace()."""
+def Trace(msg, filename=None, mode='w', tstamp=False):
+    """Write a trace message.
+
+    Write messages when debugging which do not interfere with stdout.
+    Useful in tests, which monitor stdout and would break with
+    unexpected output. Trace messages can go to the console (which is
+    opened as a file), or to a disk file; the file argument persists
+    across calls unless overridden.
+
+    Args:
+        filename: file to write trace message to. If omitted,
+          write to the previous trace file (default: console).
+        mode: file open mode (default: 'w')
+        tstamp: write relative timestamps with trace. Outputs time since
+          scons was started, and time since last trace (default: False)
+
+    """
     global TraceDefault
     global TimeStampDefault
     global PreviousTime
+
+    def traace_cleanup(traceFP):
+        traceFP.close()
+
     if file is None:
         file = TraceDefault
     else:
         TraceDefault = file
-    if tstamp is None:
+    if not tstamp:
         tstamp = TimeStampDefault
     else:
         TimeStampDefault = tstamp
@@ -225,6 +243,7 @@ def Trace(msg, file=None, mode='w', tstamp=None):
     except KeyError:
         try:
             fp = TraceFP[file] = open(file, mode)
+            atexit.register(trace_cleanup, fp)
         except TypeError:
             # Assume we were passed an open file pointer.
             fp = file
@@ -234,7 +253,6 @@ def Trace(msg, file=None, mode='w', tstamp=None):
         PreviousTime = now
     fp.write(msg)
     fp.flush()
-    fp.close()
 
 # Local Variables:
 # tab-width:4