Part 5.1: Is policy list subsumed under subsuming policy?

third_party/WebKit/Source/core/frame/csp/MediaListDirectiveTest.cpp

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "core/frame/csp/MediaListDirective.h"
+
+#include "core/frame/csp/ContentSecurityPolicy.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blink {
+
+class MediaListDirectiveTest : public ::testing::Test {
+ public:
+  MediaListDirectiveTest() : csp(ContentSecurityPolicy::create()) {}
+
+ protected:
+  Persistent<ContentSecurityPolicy> csp;
+};
+
+TEST_F(MediaListDirectiveTest, GetIntersect) {
+  MediaListDirective A(
+      "plugin-types",
+      "application/x-shockwave-flash application/pdf text/plain", csp.get());

[Mike West, 2016/12/06 13:39:07]

Can you check that we have a sane behavior when |A| is empty?

+
+  struct TestCase {
+    const char* policyB;
+    const std::vector<const char*> expected;
+  } cases[] = {
+      {"text/plain", {"text/plain"}},

[Mike West, 2016/12/06 13:39:07]

Can you add an empty list?

+      {"application/pdf", {"application/pdf"}},
+      {"application/x-shockwave-flash", {"application/x-shockwave-flash"}},
+      {"application/x-shockwave-flash text/plain",

[Mike West, 2016/12/06 13:39:07]

Nit: Can you add tests that reverse the order, just to make sure?

+       {"application/x-shockwave-flash", "text/plain"}},
+      {"application/pdf text/plain", {"text/plain", "application/pdf"}},
+      {"application/x-shockwave-flash application/pdf text/plain",
+       {"application/x-shockwave-flash", "application/pdf", "text/plain"}},

[Mike West, 2016/12/06 13:39:07]

Can you add some things like `text/`, `text/*`, and `*/plain`?

[amalika, 2016/12/06 13:54:19]

Just to make sure: None of these will be valid, right? 
From my understanding, `media-type = type "/" subtype` which does not allow any
wildcards and requires `subtype`.
(if for example, I include `text/` it does not even get stored as a value on
MediaListDirective).

+  };
+
+  for (const auto& test : cases) {
+    MediaListDirective B("plugin-types", test.policyB, csp.get());
+
+    HashSet<String> result = A.getIntersect(B.m_pluginTypes);
+    EXPECT_EQ(result.size(), test.expected.size());
+
+    for (const auto& type : test.expected)
+      EXPECT_TRUE(result.contains(type));
+  }
+}
+
+TEST_F(MediaListDirectiveTest, Subsumes) {
+  MediaListDirective A(
+      "plugin-types",
+      "application/x-shockwave-flash application/pdf text/plain", csp.get());

[Mike West, 2016/12/06 13:39:07]

Same general comments. Empty lists, wildcards, ordering.

+
+  struct TestCase {
+    const std::vector<const char*> policiesB;
+    bool subsumed;
+    bool subsumedByEmptyA;
+  } cases[] = {
+      // `A` subsumes `policiesB`.
+      {{""}, true, true},
+      {{"text/plain"}, true, false},
+      {{"application/pdf"}, true, false},
+      {{"application/x-shockwave-flash"}, true, false},
+      {{"application/x-shockwave-flash text/plain"}, true, false},
+      {{"application/pdf text/plain"}, true, false},
+      {{"application/x-shockwave-flash text/plain application/pdf"},
+       true,
+       false},
+      {{"application/x-shockwave-flash text "}, true, false},
+      {{"application/x-shockwave-flash text/plain "
+        "application/x-blink-test-plugin",
+        "application/x-shockwave-flash text/plain"},
+       true,
+       false},
+      {{"application/x-shockwave-flash text/plain "
+        "application/x-blink-test-plugin",
+        "text/plain"},
+       true,
+       false},
+      {{"application/x-blink-test-plugin", "text/plain"}, true, true},
+      {{"application/x-shockwave-flash",
+        "text/plain application/x-shockwave-flash"},
+       true,
+       false},
+      {{"application/x-shockwave-flash text/plain",
+        "application/x-blink-test-plugin", "text/plain"},
+       true,
+       true},
+      // `A` does not subsumes `policiesB`.
+      {{}, false, false},
+      {{"application/x-blink-test-plugin"}, false, false},
+      {{"application/x-shockwave-flash text/plain "
+        "application/x-blink-test-plugin"},
+       false,
+       false},
+      {{"application/x-shockwave-flash text application/x-blink-test-plugin"},
+       false,
+       false},
+      {{"application/x-invalid-type text application/"}, false, false},
+      {{"application/x-blink-test-plugin text application/",
+        "application/x-blink-test-plugin"},
+       false,
+       false},
+  };
+
+  MediaListDirective emptyA("plugin-types", "", csp.get());
+  EXPECT_TRUE(emptyA.subsumes({&emptyA}));
+
+  for (const auto& test : cases) {
+    std::vector<MediaListDirective*> policiesB;
+    for (const auto& policy : test.policiesB) {
+      policiesB.push_back(
+          new MediaListDirective("plugin-types", policy, csp.get()));
+    }
+
+    EXPECT_EQ(A.subsumes(policiesB), test.subsumed);
+    EXPECT_EQ(emptyA.subsumes(policiesB), test.subsumedByEmptyA);
+  }
+}
+
+}  // namespace blink