[Python-checkins] cpython (merge 3.5 -> default): Issue #25590: Merge rlcompleter getattr change from 3.5

[martin.panter]

https://hg.python.org/cpython/rev/ff68304356fe
changeset:   99117:ff68304356fe
parent:      99114:08c56962c24c
parent:      99116:808279e14700
user:        Martin Panter <vadmium+py at gmail.com>
date:        Fri Nov 13 23:48:17 2015 +0000
summary:
  Issue #25590: Merge rlcompleter getattr change from 3.5

files:
  Lib/rlcompleter.py           |   8 +++++---
  Lib/test/test_rlcompleter.py |  13 +++++++++++++
  Misc/NEWS                    |   3 +++
  3 files changed, 21 insertions(+), 3 deletions(-)


diff --git a/Lib/rlcompleter.py b/Lib/rlcompleter.py
--- a/Lib/rlcompleter.py
+++ b/Lib/rlcompleter.py
@@ -159,9 +159,11 @@
         while True:
             for word in words:
                 if (word[:n] == attr and
-                    not (noprefix and word[:n+1] == noprefix) and
-                    hasattr(thisobject, word)):
-                    val = getattr(thisobject, word)
+                    not (noprefix and word[:n+1] == noprefix)):
+                    try:
+                        val = getattr(thisobject, word)
+                    except Exception:
+                        continue  # Exclude properties that are not set
                     word = self._callable_postfix(val, "%s.%s" % (expr, word))
                     matches.append(word)
             if matches or not noprefix:
diff --git a/Lib/test/test_rlcompleter.py b/Lib/test/test_rlcompleter.py
--- a/Lib/test/test_rlcompleter.py
+++ b/Lib/test/test_rlcompleter.py
@@ -79,6 +79,19 @@
                          ['egg.{}('.format(x) for x in dir(str)
                           if x.startswith('s')])
 
+    def test_excessive_getattr(self):
+        # Ensure getattr() is invoked no more than once per attribute
+        class Foo:
+            calls = 0
+            @property
+            def bar(self):
+                self.calls += 1
+                return None
+        f = Foo()
+        completer = rlcompleter.Completer(dict(f=f))
+        self.assertEqual(completer.complete('f.b', 0), 'f.bar')
+        self.assertEqual(f.calls, 1)
+
     def test_complete(self):
         completer = rlcompleter.Completer()
         self.assertEqual(completer.complete('', 0), '\t')
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -402,6 +402,9 @@
 Library
 -------
 
+- Issue #25590: In the Readline completer, only call getattr() once per
+  attribute.
+
 - Issue #25498: Fix a crash when garbage-collecting ctypes objects created
   by wrapping a memoryview.  This was a regression made in 3.5a1.  Based
   on patch by Eryksun.

-- 
Repository URL: https://hg.python.org/cpython