From: José Fonseca <jose.r.fonseca@gmail.com>
Date: Tue, 12 Apr 2011 08:17:32 +0000 (+0100)
Subject: Prototype state differencing.
X-Git-Url: https://git.cworth.org/git?a=commitdiff_plain;h=0badbf001573fbbad1a6fae2b80fcacf4049b428;p=apitrace

Prototype state differencing.
---

diff --git a/scripts/jsondiff.py b/scripts/jsondiff.py
new file mode 100755
index 0000000..03e25e3
--- /dev/null
+++ b/scripts/jsondiff.py
@@ -0,0 +1,246 @@
+#!/usr/bin/env python
+##########################################################################
+#
+# Copyright 2011 Jose Fonseca
+# All Rights Reserved.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+##########################################################################/
+
+
+import json
+import sys
+
+
+def object_hook(obj):
+    if '__class__' in obj:
+        return None
+    for name in obj.keys():
+        if name.startswith('__') and name.endswith('__'):
+            del obj[name]
+    return obj
+
+
+class Visitor:
+
+    def visit(self, node, *args, **kwargs):
+        if isinstance(node, dict):
+            return self.visit_object(node, *args, **kwargs)
+        elif isinstance(node, list):
+            return self.visit_array(node, *args, **kwargs)
+        else:
+            return self.visit_value(node, *args, **kwargs)
+
+    def visit_object(self, node, *args, **kwargs):
+        pass
+
+    def visit_array(self, node, *args, **kwargs):
+        pass
+
+    def visit_value(self, node, *args, **kwargs):
+        pass
+
+
+class Dumper(Visitor):
+
+    def __init__(self):
+        self.level = 0;
+
+    def _write(self, s):
+        sys.stdout.write(s)
+
+    def _indent(self):
+        self._write('  '*self.level)
+
+    def _newline(self):
+        self._write('\n')
+
+    def visit_object(self, node):
+        self.enter_object()
+
+        members = node.keys()
+        members.sort()
+        for i in range(len(members)):
+            name = members[i]
+            value = node[name]
+            self.enter_member(name)
+            self.visit(value)
+            if i:
+                self._write(',')
+            self.leave_member()
+        self.leave_object()
+
+    def enter_object(self):
+        self._write('{')
+        self._newline()
+        self.level += 1
+
+    def enter_member(self, name):
+        self._indent()
+        self._write('%s: ' % name)
+
+    def leave_member(self):
+        self._newline()
+
+    def leave_object(self):
+        self.level -= 1
+        self._indent()
+        self._write('}')
+
+    def visit_array(self, node):
+        self.enter_array()
+        for i in range(len(node)):
+            value = node[i]
+            self._indent()
+            self.visit(value)
+            if i:
+                self._write(',')
+            self._newline()
+        self.leave_array()
+
+    def enter_array(self):
+        self._write('[')
+        self._newline()
+        self.level += 1
+
+    def leave_array(self):
+        self.level -= 1
+        self._indent()
+        self._write(']')
+
+    def visit_value(self, node):
+        self._write(repr(node))
+
+
+
+class Comparer(Visitor):
+
+    def visit_object(self, a, b):
+        if not isinstance(b, dict):
+            return False
+        if len(a) != len(b):
+            return False
+        ak = a.keys()
+        bk = b.keys()
+        ak.sort()
+        bk.sort()
+        if ak != bk:
+            return False
+        for k in ak:
+            if not self.visit(a[k], b[k]):
+                return False
+        return True
+
+    def visit_array(self, a, b):
+        if not isinstance(b, list):
+            return False
+        if len(a) != len(b):
+            return False
+        for ae, be in zip(a, b):
+            if not self.visit(ae, be):
+                return False
+        return True
+
+    def visit_value(self, a, b):
+        return a == b
+
+comparer = Comparer()
+
+
+class Differ(Visitor):
+
+    def __init__(self):
+        self.dumper = Dumper()
+
+    def visit(self, a, b):
+        if comparer.visit(a, b):
+            return
+        Visitor.visit(self, a, b)
+
+    def visit_object(self, a, b):
+        if not isinstance(b, dict):
+            self.replace(a, b)
+        else:
+            self.dumper.enter_object()
+            names = set(a.keys())
+            names.update(b.keys())
+            names = list(names)
+            names.sort()
+
+            for name in names:
+                ae = a.get(name, None)
+                be = b.get(name, None)
+                if not comparer.visit(ae, be):
+                    self.dumper.enter_member(name)
+                    self.visit(ae, be)
+                    self.dumper.leave_member()
+
+            self.dumper.leave_object()
+
+    def visit_array(self, a, b):
+        if not isinstance(b, list):
+            self.replace(a, b)
+        else:
+            self.dumper.enter_array()
+            for i in range(max(len(a), len(b))):
+                try:
+                    ae = a[i]
+                except KeyError:
+                    ae = None
+                try:
+                    be = b[i]
+                except KeyError:
+                    be = None
+                self.dumper._indent()
+                if comparer.visit(ae, be):
+                    self.dumper.visit(ae)
+                else:
+                    self.visit(ae, be)
+                self.dumper._newline()
+
+            self.dumper.leave_array()
+
+    def visit_value(self, a, b):
+        if a != b:
+            self.replace(a, b)
+
+    def replace(self, a, b):
+        self.dumper.visit(a)
+        self.dumper._write(' -> ')
+        self.dumper.visit(b)
+
+
+def load(filename):
+    return json.load(open(filename, 'rt'), strict=False, object_hook = object_hook)
+
+
+def main():
+    a = load(sys.argv[1])
+    b = load(sys.argv[2])
+
+    #dumper = Dumper()
+    #dumper.visit(a)
+
+    differ = Differ()
+    differ.visit(a, b)
+
+
+if __name__ == '__main__':
+    main()