update tests, increase coverage, add type info

22 files changed, 355 insertions, 333 deletions

diff --git a/test/mitmproxy/addons/test_dumper.py b/test/mitmproxy/addons/test_dumper.py
index 760efa08..8b15c85b 100644
--- a/test/mitmproxy/addons/test_dumper.py
+++ b/test/mitmproxy/addons/test_dumper.py
@@ -131,7 +131,7 @@ def test_echo_request_line():
 
 
 class TestContentView:
-    @mock.patch("mitmproxy.contentviews.ViewAuto.__call__")
+    @mock.patch("mitmproxy.contentviews.auto.ViewAuto.__call__")
     def test_contentview(self, view_auto):
         view_auto.side_effect = exceptions.ContentViewException("")
         sio = io.StringIO()
diff --git a/test/mitmproxy/contentviews/__init__.py b/test/mitmproxy/contentviews/__init__.py
new file mode 100644
index 00000000..9adc57ec
--- /dev/null
+++ b/test/mitmproxy/contentviews/__init__.py
@@ -0,0 +1,9 @@
+def full_eval(instance):
+    def call(data, **metadata):
+        x = instance(data, **metadata)
+        if x is None:
+            return None
+        name, generator = x
+        return name, list(generator)
+
+    return call
diff --git a/test/mitmproxy/contentviews/test_api.py b/test/mitmproxy/contentviews/test_api.py
new file mode 100644
index 00000000..37bdd40f
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_api.py
@@ -0,0 +1,85 @@
+import mock
+
+from mitmproxy import contentviews
+from mitmproxy.exceptions import ContentViewException
+from mitmproxy.net.http import Headers
+from mitmproxy.test import tutils
+
+
+class TestContentView(contentviews.View):
+    name = "test"
+    prompt = ("t", "test")
+    content_types = ["test/123"]
+
+
+def test_add_remove():
+    tcv = TestContentView()
+    contentviews.add(tcv)
+
+    # repeated addition causes exception
+    with tutils.raises(ContentViewException):
+        contentviews.add(tcv)
+
+    # Same shortcut doesn't work either.
+    with tutils.raises(ContentViewException):
+        contentviews.add(TestContentView())
+
+    contentviews.remove(tcv)
+
+
+def test_get_content_view():
+    desc, lines, err = contentviews.get_content_view(
+        contentviews.get("Raw"),
+        b"[1, 2, 3]",
+    )
+    assert "Raw" in desc
+    assert list(lines)
+    assert not err
+
+    desc, lines, err = contentviews.get_content_view(
+        contentviews.get("Auto"),
+        b"[1, 2, 3]",
+        headers=Headers(content_type="application/json")
+    )
+    assert desc == "JSON"
+
+    desc, lines, err = contentviews.get_content_view(
+        contentviews.get("JSON"),
+        b"[1, 2",
+    )
+    assert "Couldn't parse" in desc
+
+    with mock.patch("mitmproxy.contentviews.auto.ViewAuto.__call__") as view_auto:
+        view_auto.side_effect = ValueError
+
+        desc, lines, err = contentviews.get_content_view(
+            contentviews.get("Auto"),
+            b"[1, 2",
+        )
+        assert err
+        assert "Couldn't parse" in desc
+
+
+def test_get_message_content_view():
+    r = tutils.treq()
+    desc, lines, err = contentviews.get_message_content_view("raw", r)
+    assert desc == "Raw"
+
+    desc, lines, err = contentviews.get_message_content_view("unknown", r)
+    assert desc == "Raw"
+
+    r.encode("gzip")
+    desc, lines, err = contentviews.get_message_content_view("raw", r)
+    assert desc == "[decoded gzip] Raw"
+
+    r.headers["content-encoding"] = "deflate"
+    desc, lines, err = contentviews.get_message_content_view("raw", r)
+    assert desc == "[cannot decode] Raw"
+
+    r.content = None
+    desc, lines, err = contentviews.get_message_content_view("raw", r)
+    assert list(lines) == [[("error", "content missing")]]
+
+
+def test_get_by_shortcut():
+    assert contentviews.get_by_shortcut("h")
diff --git a/test/mitmproxy/contentviews/test_auto.py b/test/mitmproxy/contentviews/test_auto.py
new file mode 100644
index 00000000..a077affa
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_auto.py
@@ -0,0 +1,47 @@
+from mitmproxy.contentviews import auto
+from mitmproxy.net import http
+from mitmproxy.types import multidict
+from . import full_eval
+
+
+def test_view_auto():
+    v = full_eval(auto.ViewAuto())
+    f = v(
+        b"foo",
+        headers=http.Headers()
+    )
+    assert f[0] == "Raw"
+
+    f = v(
+        b"<html></html>",
+        headers=http.Headers(content_type="text/html")
+    )
+    assert f[0] == "HTML"
+
+    f = v(
+        b"foo",
+        headers=http.Headers(content_type="text/flibble")
+    )
+    assert f[0] == "Raw"
+
+    f = v(
+        b"<xml></xml>",
+        headers=http.Headers(content_type="text/flibble")
+    )
+    assert f[0].startswith("XML")
+
+    f = v(b"\xFF" * 30)
+    assert f[0] == "Hex"
+
+    f = v(
+        b"",
+        headers=http.Headers()
+    )
+    assert f[0] == "No content"
+
+    f = v(
+        b"",
+        headers=http.Headers(),
+        query=multidict.MultiDict([("foo", "bar")]),
+    )
+    assert f[0] == "Query"
diff --git a/test/mitmproxy/contentviews/test_css.py b/test/mitmproxy/contentviews/test_css.py
new file mode 100644
index 00000000..ecb9259b
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_css.py
@@ -0,0 +1,29 @@
+from mitmproxy.contentviews import css
+from mitmproxy.test import tutils
+from . import full_eval
+
+try:
+    import cssutils
+except:
+    cssutils = None
+
+
+def test_view_css():
+    v = full_eval(css.ViewCSS())
+
+    with open(tutils.test_data.path('mitmproxy/data/1.css'), 'r') as fp:
+        fixture_1 = fp.read()
+
+    result = v('a')
+
+    if cssutils:
+        assert len(list(result[1])) == 0
+    else:
+        assert len(list(result[1])) == 1
+
+    result = v(fixture_1)
+
+    if cssutils:
+        assert len(list(result[1])) > 1
+    else:
+        assert len(list(result[1])) == 1
diff --git a/test/mitmproxy/contentviews/test_hex.py b/test/mitmproxy/contentviews/test_hex.py
new file mode 100644
index 00000000..4292007e
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_hex.py
@@ -0,0 +1,7 @@
+from mitmproxy.contentviews import hex
+from . import full_eval
+
+
+def test_view_hex():
+    v = full_eval(hex.ViewHex())
+    assert v(b"foo")
diff --git a/test/mitmproxy/contentviews/test_html.py b/test/mitmproxy/contentviews/test_html.py
new file mode 100644
index 00000000..8d5818e5
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_html.py
@@ -0,0 +1,18 @@
+from mitmproxy.contentviews import html
+from . import full_eval
+
+
+def test_view_html():
+    v = full_eval(html.ViewHTML())
+    s = b"<html><br><br></br><p>one</p></html>"
+    assert v(s)
+
+    s = b"gobbledygook"
+    assert not v(s)
+
+
+def test_view_html_outline():
+    v = full_eval(html.ViewHTMLOutline())
+    s = b"<html><br><br></br><p>one</p></html>"
+    assert v(s)
+    assert v(b'\xfe')
diff --git a/test/mitmproxy/contentviews/test_image.py b/test/mitmproxy/contentviews/test_image.py
new file mode 100644
index 00000000..9e7e28f5
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_image.py
@@ -0,0 +1,17 @@
+from mitmproxy.contentviews import image
+from mitmproxy.test import tutils
+from . import full_eval
+
+
+def test_view_image():
+    v = full_eval(image.ViewImage())
+    for img in [
+        "mitmproxy/data/image.png",
+        "mitmproxy/data/image.gif",
+        "mitmproxy/data/image-err1.jpg",
+        "mitmproxy/data/image.ico"
+    ]:
+        with open(tutils.test_data.path(img), "rb") as f:
+            assert v(f.read())
+
+    assert not v(b"flibble")
diff --git a/test/mitmproxy/contentviews/test_javascript.py b/test/mitmproxy/contentviews/test_javascript.py
new file mode 100644
index 00000000..43039c93
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_javascript.py
@@ -0,0 +1,10 @@
+from mitmproxy.contentviews import javascript
+from . import full_eval
+
+
+def test_view_javascript():
+    v = full_eval(javascript.ViewJavaScript())
+    assert v(b"[1, 2, 3]")
+    assert v(b"[1, 2, 3")
+    assert v(b"function(a){[1, 2, 3]}")
+    assert v(b"\xfe")  # invalid utf-8
diff --git a/test/mitmproxy/contentviews/test_json.py b/test/mitmproxy/contentviews/test_json.py
new file mode 100644
index 00000000..5e87b570
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_json.py
@@ -0,0 +1,16 @@
+from mitmproxy.contentviews import json
+from . import full_eval
+
+
+def test_pretty_json():
+    assert json.pretty_json(b'{"foo": 1}')
+    assert not json.pretty_json(b"moo")
+    assert json.pretty_json(b'{"foo" : "\xe4\xb8\x96\xe7\x95\x8c"}')  # utf8 with chinese characters
+    assert not json.pretty_json(b'{"foo" : "\xFF"}')
+
+
+def test_view_json():
+    v = full_eval(json.ViewJSON())
+    assert v(b"{}")
+    assert not v(b"{")
+    assert v(b"[1, 2, 3, 4, 5]")
diff --git a/test/mitmproxy/contentviews/test_multipart.py b/test/mitmproxy/contentviews/test_multipart.py
new file mode 100644
index 00000000..48a5ccc9
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_multipart.py
@@ -0,0 +1,25 @@
+from mitmproxy.contentviews import multipart
+from mitmproxy.net import http
+from . import full_eval
+
+
+def test_view_multipart():
+    view = full_eval(multipart.ViewMultipart())
+    v = b"""
+--AaB03x
+Content-Disposition: form-data; name="submit-name"
+
+Larry
+--AaB03x
+        """.strip()
+    h = http.Headers(content_type="multipart/form-data; boundary=AaB03x")
+    assert view(v, headers=h)
+
+    h = http.Headers()
+    assert not view(v, headers=h)
+
+    h = http.Headers(content_type="multipart/form-data")
+    assert not view(v, headers=h)
+
+    h = http.Headers(content_type="unparseable")
+    assert not view(v, headers=h)
diff --git a/test/mitmproxy/contentviews/test_protobuf.py b/test/mitmproxy/contentviews/test_protobuf.py
new file mode 100644
index 00000000..1224b8db
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_protobuf.py
@@ -0,0 +1,12 @@
+from mitmproxy.contentviews import protobuf
+from mitmproxy.test import tutils
+from . import full_eval
+
+if protobuf.ViewProtobuf.is_available():
+    def test_view_protobuf_request():
+        v = full_eval(protobuf.ViewProtobuf())
+
+        p = tutils.test_data.path("mitmproxy/data/protobuf01")
+        content_type, output = v(open(p, "rb").read())
+        assert content_type == "Protobuf"
+        assert output.next()[0][1] == '1: "3bbc333c-e61c-433b-819a-0b9a8cc103b8"'
diff --git a/test/mitmproxy/contentviews/test_query.py b/test/mitmproxy/contentviews/test_query.py
new file mode 100644
index 00000000..d2bddd05
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_query.py
@@ -0,0 +1,13 @@
+from mitmproxy.contentviews import query
+from mitmproxy.types import multidict
+from . import full_eval
+
+
+def test_view_query():
+    d = ""
+    v = full_eval(query.ViewQuery())
+    f = v(d, query=multidict.MultiDict([("foo", "bar")]))
+    assert f[0] == "Query"
+    assert f[1] == [[("header", "foo: "), ("text", "bar")]]
+
+    assert v(d) == ("Query", [])
diff --git a/test/mitmproxy/contentviews/test_raw.py b/test/mitmproxy/contentviews/test_raw.py
new file mode 100644
index 00000000..0e6e1b34
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_raw.py
@@ -0,0 +1,7 @@
+from mitmproxy.contentviews import raw
+from . import full_eval
+
+
+def test_view_raw():
+    v = full_eval(raw.ViewRaw())
+    assert v(b"foo")
diff --git a/test/mitmproxy/contentviews/test_urlencoded.py b/test/mitmproxy/contentviews/test_urlencoded.py
new file mode 100644
index 00000000..d01f9aaa
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_urlencoded.py
@@ -0,0 +1,15 @@
+from mitmproxy.contentviews import urlencoded
+from mitmproxy.net.http import url
+from . import full_eval
+
+
+def test_view_urlencoded():
+    v = full_eval(urlencoded.ViewURLEncoded())
+
+    d = url.encode([("one", "two"), ("three", "four")]).encode()
+    assert v(d)
+
+    d = url.encode([("adsfa", "")]).encode()
+    assert v(d)
+
+    assert not v(b"\xFF\x00")
diff --git a/test/mitmproxy/contentviews/test_xml.py b/test/mitmproxy/contentviews/test_xml.py
new file mode 100644
index 00000000..680134cb
--- /dev/null
+++ b/test/mitmproxy/contentviews/test_xml.py
@@ -0,0 +1,17 @@
+from mitmproxy.contentviews import xml
+from . import full_eval
+
+
+def test_view_xml():
+    v = full_eval(xml.ViewXML())
+    assert v(b"<foo></foo>")
+    assert not v(b"<foo>")
+    s = b"""<?xml version="1.0" encoding="UTF-8"?>
+        <?xml-stylesheet title="XSL_formatting"?>
+        <rss
+            xmlns:media="http://search.yahoo.com/mrss/"
+            xmlns:atom="http://www.w3.org/2005/Atom"
+            version="2.0">
+        </rss>
+    """
+    assert v(s)
diff --git a/test/mitmproxy/data/amf01 b/test/mitmproxy/data/amf01
deleted file mode 100644
index c8fc261d..00000000
--- a/test/mitmproxy/data/amf01
+++ /dev/null
diff --git a/test/mitmproxy/data/amf02 b/test/mitmproxy/data/amf02
deleted file mode 100644
index ba69f130..00000000
--- a/test/mitmproxy/data/amf02
+++ /dev/null
diff --git a/test/mitmproxy/data/amf03 b/test/mitmproxy/data/amf03
deleted file mode 100644
index d9fa736a..00000000
--- a/test/mitmproxy/data/amf03
+++ /dev/null
diff --git a/test/mitmproxy/test_contentview.py b/test/mitmproxy/test_contentview.py
deleted file mode 100644
index 1f16765b..00000000
--- a/test/mitmproxy/test_contentview.py
+++ /dev/null
@@ -1,284 +0,0 @@
-import mock
-from mitmproxy.exceptions import ContentViewException
-from mitmproxy.net.http import Headers
-from mitmproxy.net.http import url
-from mitmproxy.types import multidict
-
-import mitmproxy.contentviews as cv
-from mitmproxy.test import tutils
-
-try:
-    import pyamf
-except ImportError:
-    pyamf = None
-
-try:
-    import cssutils
-except:
-    cssutils = None
-
-
-class TestContentView:
-
-    def test_view_auto(self):
-        v = cv.ViewAuto()
-        f = v(
-            b"foo",
-            headers=Headers()
-        )
-        assert f[0] == "Raw"
-
-        f = v(
-            b"<html></html>",
-            headers=Headers(content_type="text/html")
-        )
-        assert f[0] == "HTML"
-
-        f = v(
-            b"foo",
-            headers=Headers(content_type="text/flibble")
-        )
-        assert f[0] == "Raw"
-
-        f = v(
-            b"<xml></xml>",
-            headers=Headers(content_type="text/flibble")
-        )
-        assert f[0].startswith("XML")
-
-        f = v(
-            b"",
-            headers=Headers()
-        )
-        assert f[0] == "No content"
-
-        f = v(
-            b"",
-            headers=Headers(),
-            query=multidict.MultiDict([("foo", "bar")]),
-        )
-        assert f[0] == "Query"
-
-    def test_view_urlencoded(self):
-        d = url.encode([("one", "two"), ("three", "four")]).encode()
-        v = cv.ViewURLEncoded()
-        assert v(d)
-        d = url.encode([("adsfa", "")]).encode()
-        v = cv.ViewURLEncoded()
-        assert v(d)
-
-    def test_view_html(self):
-        v = cv.ViewHTML()
-        s = b"<html><br><br></br><p>one</p></html>"
-        assert v(s)
-
-        s = b"gobbledygook"
-        assert not v(s)
-
-    def test_view_html_outline(self):
-        v = cv.ViewHTMLOutline()
-        s = b"<html><br><br></br><p>one</p></html>"
-        assert v(s)
-        assert v(b'\xfe')
-
-    def test_view_json(self):
-        cv.VIEW_CUTOFF = 100
-        v = cv.ViewJSON()
-        assert v(b"{}")
-        assert not v(b"{")
-        assert v(b"[1, 2, 3, 4, 5]")
-
-    def test_view_xml(self):
-        v = cv.ViewXML()
-        assert v(b"<foo></foo>")
-        assert not v(b"<foo>")
-        s = b"""<?xml version="1.0" encoding="UTF-8"?>
-            <?xml-stylesheet title="XSL_formatting"?>
-            <rss
-                xmlns:media="http://search.yahoo.com/mrss/"
-                xmlns:atom="http://www.w3.org/2005/Atom"
-                version="2.0">
-            </rss>
-        """
-        assert v(s)
-
-    def test_view_raw(self):
-        v = cv.ViewRaw()
-        assert v(b"foo")
-
-    def test_view_javascript(self):
-        v = cv.ViewJavaScript()
-        assert v(b"[1, 2, 3]")
-        assert v(b"[1, 2, 3")
-        assert v(b"function(a){[1, 2, 3]}")
-        assert v(b"\xfe")  # invalid utf-8
-
-    def test_view_css(self):
-        v = cv.ViewCSS()
-
-        with open(tutils.test_data.path('mitmproxy/data/1.css'), 'r') as fp:
-            fixture_1 = fp.read()
-
-        result = v('a')
-
-        if cssutils:
-            assert len(list(result[1])) == 0
-        else:
-            assert len(list(result[1])) == 1
-
-        result = v(fixture_1)
-
-        if cssutils:
-            assert len(list(result[1])) > 1
-        else:
-            assert len(list(result[1])) == 1
-
-    def test_view_hex(self):
-        v = cv.ViewHex()
-        assert v(b"foo")
-
-    def test_view_image(self):
-        v = cv.ViewImage()
-        p = tutils.test_data.path("mitmproxy/data/image.png")
-        assert v(open(p, "rb").read())
-
-        p = tutils.test_data.path("mitmproxy/data/image.gif")
-        assert v(open(p, "rb").read())
-
-        p = tutils.test_data.path("mitmproxy/data/image-err1.jpg")
-        assert v(open(p, "rb").read())
-
-        p = tutils.test_data.path("mitmproxy/data/image.ico")
-        assert v(open(p, "rb").read())
-
-        assert not v(b"flibble")
-
-    def test_view_multipart(self):
-        view = cv.ViewMultipart()
-        v = b"""
---AaB03x
-Content-Disposition: form-data; name="submit-name"
-
-Larry
---AaB03x
-        """.strip()
-        h = Headers(content_type="multipart/form-data; boundary=AaB03x")
-        assert view(v, headers=h)
-
-        h = Headers()
-        assert not view(v, headers=h)
-
-        h = Headers(content_type="multipart/form-data")
-        assert not view(v, headers=h)
-
-        h = Headers(content_type="unparseable")
-        assert not view(v, headers=h)
-
-    def test_view_query(self):
-        d = ""
-        v = cv.ViewQuery()
-        f = v(d, query=multidict.MultiDict([("foo", "bar")]))
-        assert f[0] == "Query"
-        assert [x for x in f[1]] == [[("header", "foo: "), ("text", "bar")]]
-
-    def test_add_cv(self):
-        class TestContentView(cv.View):
-            name = "test"
-            prompt = ("t", "test")
-
-        tcv = TestContentView()
-        cv.add(tcv)
-
-        # repeated addition causes exception
-        tutils.raises(
-            ContentViewException,
-            cv.add,
-            tcv
-        )
-
-
-def test_get_content_view():
-    desc, lines, err = cv.get_content_view(
-        cv.get("Raw"),
-        b"[1, 2, 3]",
-    )
-    assert "Raw" in desc
-    assert list(lines)
-    assert not err
-
-    desc, lines, err = cv.get_content_view(
-        cv.get("Auto"),
-        b"[1, 2, 3]",
-        headers=Headers(content_type="application/json")
-    )
-    assert desc == "JSON"
-
-    desc, lines, err = cv.get_content_view(
-        cv.get("JSON"),
-        b"[1, 2",
-    )
-    assert "Couldn't parse" in desc
-
-    with mock.patch("mitmproxy.contentviews.ViewAuto.__call__") as view_auto:
-        view_auto.side_effect = ValueError
-
-        desc, lines, err = cv.get_content_view(
-            cv.get("Auto"),
-            b"[1, 2",
-        )
-        assert err
-        assert "Couldn't parse" in desc
-
-
-def test_get_message_content_view():
-    r = tutils.treq()
-    desc, lines, err = cv.get_message_content_view("raw", r)
-    assert desc == "Raw"
-
-    r.encode("gzip")
-    desc, lines, err = cv.get_message_content_view("raw", r)
-    assert desc == "[decoded gzip] Raw"
-
-    r.headers["content-encoding"] = "deflate"
-    desc, lines, err = cv.get_message_content_view("raw", r)
-    assert desc == "[cannot decode] Raw"
-
-    r.content = None
-    desc, lines, err = cv.get_message_content_view("raw", r)
-    assert list(lines) == [[("error", "content missing")]]
-
-
-if pyamf:
-    def test_view_amf_request():
-        v = cv.ViewAMF()
-
-        p = tutils.test_data.path("mitmproxy/data/amf01")
-        assert v(open(p, "rb").read())
-
-        p = tutils.test_data.path("mitmproxy/data/amf02")
-        assert v(open(p, "rb").read())
-
-    def test_view_amf_response():
-        v = cv.ViewAMF()
-        p = tutils.test_data.path("mitmproxy/data/amf03")
-        assert v(open(p, "rb").read())
-
-if cv.ViewProtobuf.is_available():
-    def test_view_protobuf_request():
-        v = cv.ViewProtobuf()
-
-        p = tutils.test_data.path("mitmproxy/data/protobuf01")
-        content_type, output = v(open(p, "rb").read())
-        assert content_type == "Protobuf"
-        assert output.next()[0][1] == '1: "3bbc333c-e61c-433b-819a-0b9a8cc103b8"'
-
-
-def test_get_by_shortcut():
-    assert cv.get_by_shortcut("h")
-
-
-def test_pretty_json():
-    assert cv.pretty_json(b'{"foo": 1}')
-    assert not cv.pretty_json(b"moo")
-    assert cv.pretty_json(b'{"foo" : "\xe4\xb8\x96\xe7\x95\x8c"}')  # utf8 with chinese characters
-    assert not cv.pretty_json(b'{"foo" : "\xFF"}')
diff --git a/test/mitmproxy/test_custom_contentview.py b/test/mitmproxy/test_custom_contentview.py
deleted file mode 100644
index 28f7fb33..00000000
--- a/test/mitmproxy/test_custom_contentview.py
+++ /dev/null
@@ -1,48 +0,0 @@
-import mitmproxy.contentviews as cv
-from mitmproxy.net.http import Headers
-
-
-def test_custom_views():
-    class ViewNoop(cv.View):
-        name = "noop"
-        prompt = ("noop", "n")
-        content_types = ["text/none"]
-
-        def __call__(self, data, **metadata):
-            return "noop", cv.format_text(data)
-
-    view_obj = ViewNoop()
-
-    cv.add(view_obj)
-
-    assert cv.get("noop")
-
-    r = cv.get_content_view(
-        cv.get("noop"),
-        "[1, 2, 3]",
-        headers=Headers(
-            content_type="text/plain"
-        )
-    )
-    assert "noop" in r[0]
-
-    # now try content-type matching
-    r = cv.get_content_view(
-        cv.get("Auto"),
-        "[1, 2, 3]",
-        headers=Headers(
-            content_type="text/none"
-        )
-    )
-    assert "noop" in r[0]
-
-    # now try removing the custom view
-    cv.remove(view_obj)
-    r = cv.get_content_view(
-        cv.get("Auto"),
-        b"[1, 2, 3]",
-        headers=Headers(
-            content_type="text/none"
-        )
-    )
-    assert "noop" not in r[0]
diff --git a/test/mitmproxy/utils/test_sliding_window.py b/test/mitmproxy/utils/test_sliding_window.py
new file mode 100644
index 00000000..23c76032
--- /dev/null
+++ b/test/mitmproxy/utils/test_sliding_window.py
@@ -0,0 +1,27 @@
+from mitmproxy.utils import sliding_window
+
+
+def test_simple():
+    y = list(sliding_window.window(range(1000, 1005), 1, 2))
+    assert y == [
+        # prev this  next  next2
+        (None, 1000, 1001, 1002),
+        (1000, 1001, 1002, 1003),
+        (1001, 1002, 1003, 1004),
+        (1002, 1003, 1004, None),
+        (1003, 1004, None, None)
+    ]
+
+
+def test_is_lazy():
+    done = False
+
+    def gen():
+        nonlocal done
+        done = True
+        yield 42
+
+    x = sliding_window.window(gen(), 1, 1)
+    assert not done
+    assert list(x)
+    assert done