Code mistakenly removed from the core classes

ChangeLog

@@ -1,3 +1,7 @@
+NEW IN WAF 1.7.4
+----------------
+* Fixed a regression in the Node,Task and Context classes
+
 NEW IN WAF 1.7.3
 -----------------
 * Fixed the LD_LIBRARY_PATH race condition in waf_unit_test #1200

waflib/Context.py

@@ -182,6 +182,15 @@ class Context(ctx):
 		self.exec_dict = {'ctx':self, 'conf':self, 'bld':self, 'opt':self}
 		self.logger = None
 
+	def __hash__(self):
+		"""
+		Return a hash value for storing context objects in dicts or sets. The value is not persistent.
+
+		:return: hash value
+		:rtype: int
+		"""
+		return id(self)
+
 	def load(self, tool_list, *k, **kw):
 		"""
 		Load a Waf tool as a module, and try calling the function named :py:const:`waflib.Context.Context.fun` from it.

waflib/Node.py

@@ -130,6 +130,10 @@ class Node(object):
 		"String representation (abspath), for debugging purposes"
 		return self.abspath()
 
+	def __hash__(self):
+		"Node hash, used for storage in dicts. This hash is not persistent."
+		return id(self)
+
 	def __eq__(self, node):
 		"Node comparison, based on the IDs"
 		return id(self) == id(node)

waflib/Task.py

@@ -190,6 +190,10 @@ class TaskBase(evil):
 			return 'executing: %s\n' % self.fun.__name__
 		return self.__class__.__name__ + '\n'
 
+	def __hash__(self):
+		"Very fast hashing scheme but not persistent (replace/implement in subclasses and see :py:meth:`waflib.Task.Task.uid`)"
+		return id(self)
+
 	def exec_command(self, cmd, **kw):
 		"""
 		Wrapper for :py:meth:`waflib.Context.Context.exec_command` which sets a current working directory to ``build.variant_dir``