Exception handling enhancements

waflib/Build.py

@@ -191,7 +191,7 @@ class BuildContext(Context.Context):
 
 	def __copy__(self):
 		"""Implemented to prevents copies of build contexts (raises an exception)"""
-		raise Errors.WafError('build contexts are not supposed to be copied')
+		raise Errors.WafError('build contexts cannot be copied')
 
 	def install_files(self, *k, **kw):
 		"""Actual implementation provided by :py:meth:`waflib.Build.InstallContext.install_files`"""

waflib/Context.py

@@ -416,7 +416,7 @@ class Context(ctx):
 			to_ret = STDOUT
 
 		if Logs.verbose and not kw['shell'] and not Utils.check_exe(cmd[0]):
-			raise Errors.WafError("Program %s not found!" % cmd[0])
+			raise Errors.WafError("Program %r not found!" % cmd[0])
 
 		kw['stdout'] = kw['stderr'] = subprocess.PIPE
 		if quiet is None:

waflib/Utils.py

@@ -229,7 +229,7 @@ def h_file(fname):
 		from waflib import Utils
 		def h_file(fname):
 			st = os.stat(fname)
-			if stat.S_ISDIR(st[stat.ST_MODE]): raise IOError('not a file')
+			if stat.S_ISDIR(st[stat.ST_MODE]): raise OSError('not a file')
 			s = "%s%s%s" % (st.st_mtime, st.st_size, fname)
 			return Utils.md5(s.encode()).digest()
 		Utils.h_file = h_file
@@ -290,7 +290,7 @@ def writef_win32(f, data, m='w', encoding='ISO8859-1'):
 	try:
 		fd = os.open(f, flags)
 	except OSError:
-		raise IOError('Cannot write to %r' % f)
+		raise OSError('Cannot write to %r' % f)
 	f = os.fdopen(fd, m)
 	try:
 		f.write(data)
@@ -301,7 +301,7 @@ def h_file_win32(fname):
 	try:
 		fd = os.open(fname, os.O_BINARY | os.O_RDONLY | os.O_NOINHERIT)
 	except OSError:
-		raise IOError('Cannot read from %r' % fname)
+		raise OSError('Cannot read from %r' % fname)
 	f = os.fdopen(fd, 'rb')
 	m = md5()
 	try:

waflib/fixpy2.py

@@ -61,12 +61,14 @@ def r1(code):
 	"utf-8 fixes for python < 2.6"
 	code = code.replace('as e:', ',e:')
 	code = code.replace(".decode(sys.stdout.encoding or 'iso8859-1')", '')
-	code = code.replace('.encode()', '')
-	return code
+	return code.replace('.encode()', '')
 
 @subst('Runner.py')
 def r4(code):
 	"generator syntax"
-	code = code.replace('next(self.biter)', 'self.biter.next()')
-	return code
+	return code.replace('next(self.biter)', 'self.biter.next()')
+
+@subst('Context.py')
+def r4(code):
+	return code.replace("('Execution failure: %s'%str(e),ex=e)", "('Execution failure: %s'%str(e),ex=e),None,sys.exc_info()[2]")