Added doctest encoding command line option

_pytest/doctest.py

@@ -43,6 +43,10 @@ def pytest_addoption(parser):
         action="store_true", default=False,
         help="ignore doctest ImportErrors",
         dest="doctest_ignore_import_errors")
+    group.addoption("--doctest-encoding",
+        type=str.lower, default="utf-8",
+        help="choose the encoding to use for doctest files",
+        dest="doctestencoding")
 
 
 def pytest_collect_file(path, parent):
@@ -171,7 +175,7 @@ def collect(self):
 
         # inspired by doctest.testfile; ideally we would use it directly,
         # but it doesn't support passing a custom checker
-        text = self.fspath.read()
+        text = self.fspath.read_text(self.config.getoption("doctestencoding"))
         filename = str(self.fspath)
         name = self.fspath.basename
         globs = {'__name__': '__main__'}

_pytest/pytester.py

@@ -471,7 +471,7 @@ def chdir(self):
         if not hasattr(self, '_olddir'):
             self._olddir = old
 
-    def _makefile(self, ext, args, kwargs):
+    def _makefile(self, ext, args, kwargs, encoding="utf-8"):
         items = list(kwargs.items())
         if args:
             source = py.builtin._totext("\n").join(
@@ -490,7 +490,7 @@ def my_totext(s, encoding="utf-8"):
 
             source_unicode = "\n".join([my_totext(line) for line in source.lines])
             source = py.builtin._totext(source_unicode)
-            content = source.strip().encode("utf-8") # + "\n"
+            content = source.strip().encode(encoding) # + "\n"
             #content = content.rstrip() + "\n"
             p.write(content, "wb")
             if ret is None:

doc/en/doctest.rst

@@ -11,6 +11,13 @@ can change the pattern by issuing::
 on the command line. Since version ``2.9``, ``--doctest-glob``
 can be given multiple times in the command-line.
 
+You can specify the encoding that will be used for those doctest files
+using the ``--doctest-encoding`` command line option::
+
+    pytest --doctest-encoding='ascii'
+
+The default encoding is UTF-8.
+
 You can also trigger running of doctests
 from docstrings in all python modules (including regular
 python test modules)::
@@ -52,9 +59,9 @@ then you can just invoke ``pytest`` without command line options::
     platform linux -- Python 3.5.2, pytest-3.0.4, py-1.4.31, pluggy-0.4.0
     rootdir: $REGENDOC_TMPDIR, inifile: pytest.ini
     collected 1 items
-    
+
     mymodule.py .
-    
+
     ======= 1 passed in 0.12 seconds ========
 
 It is possible to use fixtures using the ``getfixture`` helper::

testing/test_doctest.py

@@ -129,6 +129,52 @@ def test_multiple_patterns(self, testdir):
             '*1 passed*',
         ])
 
+    def test_encoding_ascii(self, testdir):
+        """Test support for --doctest-encoding option.
+        """
+        testdir._makefile(".txt", ["""
+            >>> 1
+            1
+        """], {}, encoding='ascii')
+
+        result = testdir.runpytest("--doctest-encoding=ascii")
+
+        result.stdout.fnmatch_lines([
+            '*1 passed*',
+        ])
+
+    def test_encoding_latin1(self, testdir):
+        """Test support for --doctest-encoding option.
+        """
+        testdir._makefile(".txt", ["""
+            >>> 'üäö'
+            'üäö'
+        """], {}, encoding='latin1')
+
+        result = testdir.runpytest("--doctest-encoding=latin1")
+
+        result.stdout.fnmatch_lines([
+            '*1 passed*',
+        ])
+
+    def test_encoding_utf8(self, testdir):
+        """Test support for --doctest-encoding option.
+        """
+        testdir.maketxtfile("""
+            >>> 'üäö'
+            'üäö'
+        """)
+
+        result = testdir.runpytest()
+        result.stdout.fnmatch_lines([
+            '*1 passed*',
+        ])
+
+        result = testdir.runpytest("--doctest-encoding=utf-8")
+        result.stdout.fnmatch_lines([
+            '*1 passed*',
+        ])
+
     def test_doctest_unexpected_exception(self, testdir):
         testdir.maketxtfile("""
             >>> i = 0