Merged revisions 62734,62736,62748,62769 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

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  r62734 | brett.cannon | 2008-05-05 22:21:38 +0200 (Mon, 05 May 2008) | 5 lines

  Add the 'json' package. Code taken from simplejson 1.9 and contributed by Bob
  Ippolito.

  Closes issue #2750.
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  r62736 | georg.brandl | 2008-05-05 22:53:39 +0200 (Mon, 05 May 2008) | 2 lines

  Fix JSON module docs.
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  r62748 | benjamin.peterson | 2008-05-06 04:51:10 +0200 (Tue, 06 May 2008) | 2 lines

  PEP 8 nits in json package
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  r62769 | christian.heimes | 2008-05-06 18:18:41 +0200 (Tue, 06 May 2008) | 2 lines

  Intern static string
  Use float constructors instead of magic code for float constants
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Lib/json/tests/test_recursion.py

@@ -0,0 +1,67 @@
+from unittest import TestCase
+
+import json
+
+class JSONTestObject:
+    pass
+
+
+class RecursiveJSONEncoder(json.JSONEncoder):
+    recurse = False
+    def default(self, o):
+        if o is JSONTestObject:
+            if self.recurse:
+                return [JSONTestObject]
+            else:
+                return 'JSONTestObject'
+        return json.JSONEncoder.default(o)
+
+
+class TestRecursion(TestCase):
+    def test_listrecursion(self):
+        x = []
+        x.append(x)
+        try:
+            json.dumps(x)
+        except ValueError:
+            pass
+        else:
+            self.fail("didn't raise ValueError on list recursion")
+        x = []
+        y = [x]
+        x.append(y)
+        try:
+            json.dumps(x)
+        except ValueError:
+            pass
+        else:
+            self.fail("didn't raise ValueError on alternating list recursion")
+        y = []
+        x = [y, y]
+        # ensure that the marker is cleared
+        json.dumps(x)
+
+    def test_dictrecursion(self):
+        x = {}
+        x["test"] = x
+        try:
+            json.dumps(x)
+        except ValueError:
+            pass
+        else:
+            self.fail("didn't raise ValueError on dict recursion")
+        x = {}
+        y = {"a": x, "b": x}
+        # ensure that the marker is cleared
+        json.dumps(x)
+
+    def test_defaultrecursion(self):
+        enc = RecursiveJSONEncoder()
+        self.assertEquals(enc.encode(JSONTestObject), '"JSONTestObject"')
+        enc.recurse = True
+        try:
+            enc.encode(JSONTestObject)
+        except ValueError:
+            pass
+        else:
+            self.fail("didn't raise ValueError on default recursion")