text: import io
  
  from django.conf import settings
  from django.core.cache import cache
  from django.http import HttpResponse
  from django.http.response import HttpResponseBase
  from django.test import SimpleTestCase
  
  UTF8 = 'utf-8'
  ISO88591 = 'iso-8859-1'
  
  
  class HttpResponseBaseTests(SimpleTestCase):
      def test_closed(self):
          r = HttpResponseBase()
          self.assertIs(r.closed, False)
  
          r.close()
          self.assertIs(r.closed, True)
  
      def test_write(self):
          r = HttpResponseBase()
          self.assertIs(r.writable(), False)
  
          with self.assertRaisesMessage(OSError, 'This HttpResponseBase instance is not writable'):
              r.write('asdf')
          with self.assertRaisesMessage(OSError, 'This HttpResponseBase instance is not writable'):
              r.writelines(['asdf\n', 'qwer\n'])
  
      def test_tell(self):
          r = HttpResponseBase()
          with self.assertRaisesMessage(OSError, 'This HttpResponseBase instance cannot tell its position'):
              r.tell()
  
      def test_setdefault(self):
          """
          HttpResponseBase.setdefault() should not change an existing header
          and should be case insensitive.
          """
          r = HttpResponseBase()
  
          r['Header'] = 'Value'
          r.setdefault('header', 'changed')
          self.assertEqual(r['header'], 'Value')
  
          r.setdefault('x-header', 'DefaultValue')
          self.assertEqual(r['X-Header'], 'DefaultValue')
  
  
  class HttpResponseTests(SimpleTestCase):
      def test_status_code(self):
          resp = HttpResponse(status=503)
          self.assertEqual(resp.status_code, 503)
          self.assertEqual(resp.reason_phrase, "Service Unavailable")
  
      def test_change_status_code(self):
          resp = HttpResponse()
          resp.status_code = 503
          self.assertEqual(resp.status_code, 503)
          self.assertEqual(resp.reason_phrase, "Service Unavailable")
  
      def test_valid_status_code_string(self):
          resp = HttpResponse(status='100')
          self.assertEqual(resp.status_code, 100)
          resp = HttpResponse(status='404')
          self.assertEqual(resp.status_code, 404)
          resp = HttpResponse(status='599')
          self.assertEqual(resp.status_code, 599)
  
      def test_invalid_status_code(self):
          must_be_integer = 'HTTP status code must be an integer.'
          must_be_integer_in_range = 'HTTP status code must be an integer from 100 to 599.'
          with self.assertRaisesMessage(TypeError, must_be_integer):
              HttpResponse(status=object())
          with self.assertRaisesMessage(TypeError, must_be_integer):
              HttpResponse(status="J'attendrai")
          with self.assertRaisesMessage(ValueError, must_be_integer_in_range):
              HttpResponse(status=99)
          with self.assertRaisesMessage(ValueError, must_be_integer_in_range):
              HttpResponse(status=600)
  
      def test_reason_phrase(self):
          reason = "I'm an anarchist coffee pot on crack."
          resp = HttpResponse(status=419, reason=reason)
          self.assertEqual(resp.status_code, 419)
          self.assertEqual(resp.reason_phrase, reason)
  
      def test_charset_detection(self):
          """ HttpResponse should parse charset from content_type."""
          response = HttpResponse('ok')
          self.assertEqual(response.charset, settings.DEFAULT_CHARSET)
  
          response = HttpResponse(charset=ISO88591)
          self.assertEqual(response.charset, ISO88591)
          self.assertEqual(response['Content-Type'], 'text/html; charset=%s' % ISO88591)
  
          response = HttpResponse(content_type='text/plain; charset=%s' % UTF8, charset=ISO88591)
          self.assertEqual(response.charset, ISO88591)
  
          response = HttpResponse(content_type='text/plain; charset=%s' % ISO88591)
          self.assertEqual(response.charset, ISO88591)
  
          response = HttpResponse(content_type='text/plain; charset="%s"' % ISO88591)
          self.assertEqual(response.charset, ISO88591)
  
          response = HttpResponse(content_type='text/plain; charset=')
          self.assertEqual(response.charset, settings.DEFAULT_CHARSET)
  
          response = HttpResponse(content_type='text/plain')
          self.assertEqual(response.charset, settings.DEFAULT_CHARSET)
  
      def test_response_content_charset(self):
          """HttpResponse should encode based on charset."""
          content = "Café :)"
          utf8_content = content.encode(UTF8)
          iso_content = content.encode(ISO88591)
  
          response = HttpResponse(utf8_content)
          self.assertContains(response, utf8_content)
  
          response = HttpResponse(iso_content, content_type='text/plain; charset=%s' % ISO88591)
          self.assertContains(response, iso_content)
  
          response = HttpResponse(iso_content)
          self.assertContains(response, iso_content)
  
          response = HttpResponse(iso_content, content_type='text/plain')
          self.assertContains(response, iso_content)
  
      def test_repr(self):
          response = HttpResponse(content="Café :)".encode(UTF8), status=201)
          expected = '<HttpResponse status_code=201, "text/html; charset=utf-8">'
          self.assertEqual(repr(response), expected)
  
      def test_repr_no_content_type(self):
          response = HttpResponse(status=204)
          del response['Content-Type']
          self.assertEqual(repr(response), '<HttpResponse status_code=204>')
  
      def test_wrap_textiowrapper(self):
          content = "Café :)"
          r = HttpResponse()
          with io.TextIOWrapper(r, UTF8) as buf:
              buf.write(content)
          self.assertEqual(r.content, content.encode(UTF8))
  
      def test_generator_cache(self):
          generator = (str(i) for i in range(10))
          response = HttpResponse(content=generator)
          self.assertEqual(response.content, b'0123456789')
          with self.assertRaises(StopIteration):
              next(generator)
  
          cache.set('my-response-key', response)
          response = cache.get('my-response-key')
          self.assertEqual(response.content, b'0123456789')
  