diff options
Diffstat (limited to 'Lib/tempfile.py')
-rw-r--r-- | Lib/tempfile.py | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/Lib/tempfile.py b/Lib/tempfile.py index d725a9d..4f27f61 100644 --- a/Lib/tempfile.py +++ b/Lib/tempfile.py @@ -363,6 +363,7 @@ def mktemp(suffix="", prefix=template, dir=None): raise IOError(_errno.EEXIST, "No usable temporary filename found") + class _TemporaryFileWrapper: """Temporary file wrapper @@ -378,17 +379,25 @@ class _TemporaryFileWrapper: self.delete = delete def __getattr__(self, name): + # Attribute lookups are delegated to the underlying file + # and cached for non-numeric results + # (i.e. methods are cached, closed and friends are not) file = self.__dict__['file'] a = getattr(file, name) - if type(a) != type(0): + if not isinstance(a, int): setattr(self, name, a) return a + # The underlying __enter__ method returns the wrong object + # (self.file) so override it to return the wrapper + def __enter__(self): + self.file.__enter__() + return self + # NT provides delete-on-close as a primitive, so we don't need # the wrapper to do anything special. We still use it so that # file.name is useful (i.e. not "(fdopen)") with NamedTemporaryFile. if _os.name != 'nt': - # Cache the unlinker so we don't get spurious errors at # shutdown when the module-level "os" is None'd out. Note # that this must be referenced as self.unlink, because the @@ -406,6 +415,14 @@ class _TemporaryFileWrapper: def __del__(self): self.close() + # Need to trap __exit__ as well to ensure the file gets + # deleted when used in a with statement + def __exit__(self, exc, value, tb): + result = self.file.__exit__(exc, value, tb) + self.close() + return result + + def NamedTemporaryFile(mode='w+b', buffering=-1, encoding=None, newline=None, suffix="", prefix=template, dir=None, delete=True): @@ -523,6 +540,20 @@ class SpooledTemporaryFile: self._rolled = True + # The method caching trick from NamedTemporaryFile + # won't work here, because _file may change from a + # _StringIO instance to a real file. So we list + # all the methods directly. + + # Context management protocol + def __enter__(self): + if self._file.closed: + raise ValueError("Cannot enter context with closed file") + return self + + def __exit__(self, exc, value, tb): + self._file.close() + # file protocol def __iter__(self): return self._file.__iter__() |