Moved the command hashing logic into a utility function

waflib/Task.py

@@ -81,11 +81,10 @@ class store_task_type(type):
 			name = name.replace('_task', '')
 		if name != 'evil' and name != 'TaskBase':
 			global classes
-
 			if getattr(cls, 'run_str', None):
 				# if a string is provided, convert it to a method
 				(f, dvars) = compile_fun(cls.run_str, cls.shell)
-				cls.hcode = str(cls.run_str)
+				cls.hcode = Utils.h_cmd(cls.run_str)
 				cls.orig_run_str = cls.run_str
 				# change the name of run_str or it is impossible to subclass with a function
 				cls.run_str = None
@@ -94,10 +93,7 @@ class store_task_type(type):
 				cls.vars.sort()
 			elif getattr(cls, 'run', None) and not 'hcode' in cls.__dict__:
 				# getattr(cls, 'hcode') would look in the upper classes
-				cls.hcode = Utils.h_fun(cls.run)
-
-			if sys.hexversion > 0x3000000:
-				cls.hcode = cls.hcode.encode('iso8859-1', 'xmlcharrefreplace')
+				cls.hcode = Utils.h_cmd(cls.run)
 
 			# be creative
 			getattr(cls, 'register', classes)[name] = cls

waflib/Utils.py

@@ -441,6 +441,7 @@ def check_dir(path):
 def check_exe(name, env=None):
 	"""
 	Ensure that a program exists
+
 	:type name: string
 	:param name: name or path to program
 	:return: path of the program or None
@@ -523,6 +524,25 @@ def h_fun(fun):
 			pass
 		return h
 
+def h_cmd(ins):
+	"""
+	Task command hashes are calculated by calling this function. The inputs can be
+	strings, functions, tuples/lists containing strings/functions
+	"""
+	# this function is not meant to be particularly fast
+	if isinstance(ins, str):
+		# a command is either a string
+		ret = ins
+	elif isinstance(ins, list) or isinstance(ins, tuple):
+		# or a list of functions/strings
+		ret = str([h_cmd(x) for x in ins])
+	else:
+		# or just a python function
+		ret = str(h_fun(ins))
+	if sys.hexversion > 0x3000000:
+		ret = ret.encode('iso8859-1', 'xmlcharrefreplace')
+	return ret
+
 reg_subst = re.compile(r"(\\\\)|(\$\$)|\$\{([^}]+)\}")
 def subst_vars(expr, params):
 	"""