print_: encode unicode with file encoding and errors on Python 2 (fixes #35)

3 files changed, 35 insertions, 0 deletions

diff --git a/CHANGES b/CHANGES
index 0701148..78dc08f 100644
--- a/CHANGES
+++ b/CHANGES
@@ -3,6 +3,13 @@ Changelog for Six
 
 This file lists the changes in each six version.
 
+Development version
+-------------------
+
+- Issue #35: On Python versions less than 2.7, print_ now encodes unicode
+  strings when outputing to standard streams. (Python 2.7 handles this
+  automatically.)
+
 1.4.1
 -----
 
diff --git a/six.py b/six.py
index 85898ec..860d506 100644
--- a/six.py
+++ b/six.py
@@ -521,6 +521,16 @@ else:
         def write(data):
             if not isinstance(data, basestring):
                 data = str(data)
+            # If the file has an encoding, encode unicode with it. In Python
+            # 2.7, file.write handles this.
+            if (sys.version_info[1] < 7 and
+                isinstance(fp, file) and
+                isinstance(data, unicode) and
+                fp.encoding is not None):
+                errors = getattr(fp, "errors", None)
+                if errors is None:
+                    errors = "strict"
+                data = data.encode(fp.encoding, errors)
             fp.write(data)
         want_unicode = False
         sep = kwargs.pop("sep", None)
diff --git a/test_six.py b/test_six.py
index 81d1776..37fa6fa 100644
--- a/test_six.py
+++ b/test_six.py
@@ -528,6 +528,24 @@ def test_print_():
     assert out.getvalue() == "None\n"
 
 
+@py.test.mark.skipif("sys.version_info[:2] >= (2, 7)")
+def test_print_encoding(monkeypatch):
+    # Fool the type checking print_.
+    monkeypatch.setattr(six, "file", six.BytesIO, raising=False)
+    out = six.BytesIO()
+    out.encoding = "utf-8"
+    out.errors = None
+    six.print_(six.u("\u053c"), end="", file=out)
+    assert out.getvalue() == six.b("\xd4\xbc")
+    out = six.BytesIO()
+    out.encoding = "ascii"
+    out.errors = "strict"
+    py.test.raises(UnicodeEncodeError, six.print_, six.u("\u053c"), file=out)
+    out.errors = "backslashreplace"
+    six.print_(six.u("\u053c"), end="", file=out)
+    assert out.getvalue() == six.b("\\u053c")
+
+
 def test_print_exceptions():
     py.test.raises(TypeError, six.print_, x=3)
     py.test.raises(TypeError, six.print_, end=3)