[pypy-commit] pypy py3.3: Merged in numerodix/pypy/py3.3-fixes2 (pull request #269)

[pjenvey]

Author: Philip Jenvey <pjenvey at underboss.org>
Branch: py3.3
Changeset: r72844:eda8876b5645
Date: 2014-08-17 10:34 -0700
http://bitbucket.org/pypy/pypy/changeset/eda8876b5645/

Log:	Merged in numerodix/pypy/py3.3-fixes2 (pull request #269)

	py3.3: implement flush kwarg for print()

diff --git a/pypy/module/__builtin__/app_io.py b/pypy/module/__builtin__/app_io.py
--- a/pypy/module/__builtin__/app_io.py
+++ b/pypy/module/__builtin__/app_io.py
@@ -57,13 +57,14 @@
     return line
 
 def print_(*args, **kwargs):
-    r"""print(value, ..., sep=' ', end='\n', file=sys.stdout)
+    r"""print(value, ..., sep=' ', end='\n', file=sys.stdout, flush=False)
 
     Prints the values to a stream, or to sys.stdout by default.
     Optional keyword arguments:
-    file: a file-like object (stream); defaults to the current sys.stdout.
-    sep:  string inserted between values, default a space.
-    end:  string appended after the last value, default a newline.
+    file:  a file-like object (stream); defaults to the current sys.stdout.
+    sep:   string inserted between values, default a space.
+    end:   string appended after the last value, default a newline.
+    flush: whether to forcibly flush the stream.
     """
     fp = kwargs.pop("file", None)
     if fp is None:
@@ -80,6 +81,7 @@
     if end is not None:
         if not isinstance(end, str):
             raise TypeError("end must be None or a string")
+    flush = kwargs.pop('flush', None)
     if kwargs:
         raise TypeError("invalid keyword arguments to print()")
     if sep is None:
@@ -91,3 +93,5 @@
             write(sep)
         write(arg)
     write(end)
+    if flush:
+        fp.flush()
diff --git a/pypy/module/__builtin__/test/test_print.py b/pypy/module/__builtin__/test/test_print.py
new file mode 100644
--- /dev/null
+++ b/pypy/module/__builtin__/test/test_print.py
@@ -0,0 +1,29 @@
+class AppTestPrint:
+
+    def test_print_flush(self):
+        """
+        # operation of the flush flag
+        class filelike():
+            def __init__(self):
+                self.written = ''
+                self.flushed = 0
+            def write(self, str):
+                self.written += str
+            def flush(self):
+                self.flushed += 1
+
+        f = filelike()
+        print(1, file=f, end='', flush=True)
+        print(2, file=f, end='', flush=True)
+        print(3, file=f, flush=False)
+        assert f.written == '123\\n'
+        assert f.flushed == 2
+
+        # ensure exceptions from flush are passed through
+        class noflush():
+            def write(self, str):
+                pass
+            def flush(self):
+                raise RuntimeError
+        raises(RuntimeError, print, 1, file=noflush(), flush=True)
+        """