Shorten "progress" information, and make sure it never extend 80 columns.

dart/tools/build.py

 #!/usr/bin/env python
 #
 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 #
 
 import optparse
 import os
+import re
 import shutil
 import subprocess
 import sys
 import utils
 
 HOST_OS = utils.GuessOS()
 HOST_CPUS = utils.GuessCpus()
 armcompilerlocation = '/opt/codesourcery/arm-2009q1'
 SCRIPT_DIR = os.path.dirname(sys.argv[0])
 DART_ROOT = os.path.realpath(os.path.join(SCRIPT_DIR, '..'))
@@ skipping 246 matching lines @@
     term = os.getenv('TERM', 'dumb')
     # The capability "clr_eol" means clear the line from cursor to end
     # of line.  See man pages for tput and terminfo.
     try:
       clr_eol = subprocess.check_output(['tput', '-T' + term, 'el'],
                                         stderr=subprocess.STDOUT)
       if clr_eol:
         is_fancy_tty = True
     except subprocess.CalledProcessError:
       is_fancy_tty = False
+  pattern = re.compile(r'=== BUILD .* TARGET (.*) OF PROJECT (.*) WITH ' +
+                       r'CONFIGURATION (.*) ===')
   has_interesting_info = False
   for line in unbuffered(process.stdout.readline):
     line = line.rstrip()
     if line.startswith('=== BUILD ') or line.startswith('** BUILD '):
       has_interesting_info = False
       section = line
       if is_fancy_tty:
+        match = re.match(pattern, section)
+        if match:
+          section = '%s/%s/%s' % (
+            match.group(3), match.group(2), match.group(1))
+        # Truncate to avoid extending beyond 80 columns.
+        section = section[:80]
         # If stdout is a terminal, emit "progress" information.  The
         # progress information is the first line of the current chunk.
         # After printing the line, move the cursor back to the
         # beginning of the line.  This has two effects: First, if the
         # chunk isn't empty, the first line will be overwritten
         # (avoiding duplication).  Second, the next segment line will
         # overwrite it too avoid long scrollback.  clr_eol ensures
         # that there is no trailing garbage when a shorter line
         # overwrites a longer line.
         print '%s%s\r' % (clr_eol, section),
@@ skipping 121 matching lines @@
         process.wait()
         if process.returncode != 0:
           print "BUILD FAILED"
           return 1
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(Main())