1 files changed, 36 insertions, 0 deletions
diff --git a/Lib/test/test_pprint.py b/Lib/test/test_pprint.py
new file mode 100644
index 0000000000..610e989e51
--- /dev/null
+++ b/Lib/test/test_pprint.py
@@ -0,0 +1,36 @@
+from test_support import verify
+import pprint
+
+# Verify that .isrecursive() and .isreadable() work.
+
+a = range(100)
+b = range(200)
+a[-12] = b
+
+for safe in 2, 2.0, 2j, "abc", [3], (2,2), {3: 3}, u"yaddayadda", a, b:
+    verify(pprint.isrecursive(safe) == 0, "expected isrecursive == 0")
+    verify(pprint.isreadable(safe) == 1,  "expected isreadable == 1")
+
+# Tie a knot.
+b[67] = a
+# Messy dict.
+d = {}
+d[0] = d[1] = d[2] = d
+
+for icky in a, b, d, (d, d):
+    verify(pprint.isrecursive(icky) == 1, "expected isrecursive == 1")
+    verify(pprint.isreadable(icky) == 0,  "expected isreadable == 0")
+
+# Break the cycles.
+d.clear()
+del a[:]
+del b[:]
+
+for safe in a, b, d, (d, d):
+    verify(pprint.isrecursive(safe) == 0, "expected isrecursive == 0")
+    verify(pprint.isreadable(safe) == 1,  "expected isreadable == 1")
+
+# Not recursive but not readable anyway.
+for unreadable in type(3), pprint, pprint.isrecursive:
+    verify(pprint.isrecursive(unreadable) == 0, "expected isrecursive == 0")
+    verify(pprint.isreadable(unreadable) ==0,  "expected isreadable == 0")