Find the order that follows the alphabet

tests/post/wscript

@@ -0,0 +1,66 @@
+#! /usr/bin/env python
+# encoding: utf-8
+# Thomas Nagy, 2017 (ita)
+
+top = '.'
+out = 'build'
+
+import inspect
+from waflib import Utils, Logs, TaskGen
+
+@TaskGen.taskgen_method
+def log(self):
+	fname = inspect.stack()[1][3]
+	try:
+		self.called.append(fname)
+	except AttributeError:
+		self.called = [fname]
+
+@TaskGen.taskgen_method
+def check(self):
+	self.post()
+	result = ''.join(self.called)
+	if result == self.expected:
+		color = 'GREEN'
+	else:
+		color = 'RED'
+		result = 'got %r but expected %r' % (result, self.expected)
+		self.bld.failure = 1
+	Logs.pprint(color, result)
+
+@TaskGen.feature('test1')
+@TaskGen.after('d')
+def a(self):
+	self.log()
+@TaskGen.feature('test1')
+@TaskGen.after('c')
+def b(self):
+	self.log()
+@TaskGen.feature('test1')
+def c(self):
+	self.log()
+@TaskGen.feature('test1')
+def d(self):
+	self.log()
+@TaskGen.feature('test1')
+@TaskGen.after('f')
+def e(self):
+	self.log()
+@TaskGen.feature('test1')
+def f(self):
+	self.log()
+
+
+def configure(conf):
+	pass
+
+def build(bld):
+
+	bld.failure = 0
+	def stop_status(bld):
+		if bld.failure:
+			bld.fatal('One or several test failed, check the outputs above')
+	bld.add_post_fun(stop_status)
+
+	bld(features='test1', expected='cbdafe').check()
+

waflib/TaskGen.py

@@ -190,7 +190,7 @@ class task_gen(object):
 			else:
 				tmp.append(a)
 
-		tmp.sort()
+		tmp.sort(reverse=True)
 
 		# topological sort
 		out = []
@@ -210,13 +210,13 @@ class task_gen(object):
 							break
 					else:
 						tmp.append(x)
+						tmp.sort(reverse=True)
 
 		if prec:
 			buf = ['Cycle detected in the method execution:']
 			for k, v in prec.items():
 				buf.append('- %s after %s' % (k, [x for x in v if x in prec]))
 			raise Errors.WafError('\n'.join(buf))
-		out.reverse()
 		self.meths = out
 
 		# then we run the methods in order
@@ -430,7 +430,7 @@ def before_method(*k):
 	def deco(func):
 		setattr(task_gen, func.__name__, func)
 		for fun_name in k:
-			task_gen.prec[fun_name].add(func.__name__)
+			task_gen.prec[func.__name__].add(fun_name)
 		return func
 	return deco
 before = before_method
@@ -457,7 +457,7 @@ def after_method(*k):
 	def deco(func):
 		setattr(task_gen, func.__name__, func)
 		for fun_name in k:
-			task_gen.prec[func.__name__].add(fun_name)
+			task_gen.prec[fun_name].add(func.__name__)
 		return func
 	return deco
 after = after_method