Add infrastructure for a USB device blocklist.

chrome/browser/usb/usb_blocklist_unittest.cc

Index: chrome/browser/usb/usb_blocklist_unittest.cc
diff --git a/chrome/browser/usb/usb_blocklist_unittest.cc b/chrome/browser/usb/usb_blocklist_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7855048de6e5d71887c1e6f33a8360aa4fa19c49
--- /dev/null
+++ b/chrome/browser/usb/usb_blocklist_unittest.cc
@@ -0,0 +1,96 @@
+// Copyright 2016 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 "base/metrics/field_trial.h"
+#include "chrome/browser/usb/usb_blocklist.h"
+#include "components/variations/variations_associated_data.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+class UsbBlocklistTest : public testing::Test {
+ public:
+  UsbBlocklistTest()
+      : field_trial_list_(new base::FieldTrialList(nullptr)),
+        list_(UsbBlocklist::Get()) {}
+
+  void TearDown() override {
+    // Because UsbBlocklist is a singleton it must be cleared after tests run
+    // to prevent leakage between tests.
+    field_trial_list_.reset();
+    list_.ResetToDefaultValuesForTest();
+  }
+
+  std::unique_ptr<base::FieldTrialList> field_trial_list_;
+  UsbBlocklist& list_;
+};
+
+TEST_F(UsbBlocklistTest, BasicExclusions) {
+  list_.Exclude({0x18D1, 0x58F0, 0x0100});
+  EXPECT_TRUE(list_.IsExcluded({0x18D1, 0x58F0, 0x0100}));
+  EXPECT_FALSE(list_.IsExcluded({0x18D1, 0x58F1, 0x0100}));
+  EXPECT_FALSE(list_.IsExcluded({0x18D0, 0x58F0, 0x0100}));
+  EXPECT_FALSE(list_.IsExcluded({0x18D1, 0x58F0, 0x0200}));
+}
+
+TEST_F(UsbBlocklistTest, StringsWithNoValidEntries) {
+  size_t previous_list_size = list_.size();
+  list_.Exclude("");
+  list_.Exclude("~!@#$%^&*()-_=+[]{}/*-");
+  list_.Exclude(":");
+  list_.Exclude("::");
+  list_.Exclude(",");
+  list_.Exclude(",,");
+  list_.Exclude(",::,");
+  list_.Exclude("1:2:3");
+  list_.Exclude("18D1:2:3000");
+  list_.Exclude("☯");
+  EXPECT_EQ(previous_list_size, list_.size());
+}
+
+TEST_F(UsbBlocklistTest, StringsWithOneValidEntry) {
+  size_t previous_list_size = list_.size();
+  list_.Exclude("18D1:58F0:0101");
+  EXPECT_EQ(++previous_list_size, list_.size());
+  EXPECT_TRUE(list_.IsExcluded({0x18D1, 0x58F0, 0x0101}));
+
+  list_.Exclude(" 18D1:58F0:0200  ");
+  EXPECT_EQ(++previous_list_size, list_.size());
+  EXPECT_TRUE(list_.IsExcluded({0x18D1, 0x58F0, 0x0200}));
+
+  list_.Exclude(", 18D1:58F0:0201,  ");
+  EXPECT_EQ(++previous_list_size, list_.size());
+  EXPECT_TRUE(list_.IsExcluded({0x18D1, 0x58F0, 0x0201}));
+
+  list_.Exclude("18D1:58F0:0202, 0000:1:0000");
+  EXPECT_EQ(++previous_list_size, list_.size());
+  EXPECT_TRUE(list_.IsExcluded({0x18D1, 0x58F0, 0x0202}));
+}
+
+TEST_F(UsbBlocklistTest, ServerProvidedBlocklist) {
+  if (base::FieldTrialList::TrialExists("WebUSBBlocklist")) {
+    // This code checks to make sure that when a field trial is launched it
+    // still contains our test data.
+    LOG(INFO) << "WebUSBBlocklist field trial already configured.";
+    ASSERT_NE(variations::GetVariationParamValue("WebUSBBlocklist",
+                                                 "blocklist_additions")
+                  .find("18D1:58F0:1BAD"),
+              std::string::npos)
+        << "ERROR: A WebUSBBlocklist field trial has been configured in\n"
+           "testing/variations/fieldtrial_testing_config.json and must\n"
+           "include this test's excluded device ID '18D1:58F0:1BAD' in\n"
+           "blocklist_additions.\n";
+  } else {
+    LOG(INFO) << "Creating WebUSBBlocklist field trial for test.";
+    // Create a field trial with test parameter.
+    std::map<std::string, std::string> params;
+    params["blocklist_additions"] = "18D1:58F0:1BAD";
+    variations::AssociateVariationParams("WebUSBBlocklist", "TestGroup",
+                                         params);
+    base::FieldTrialList::CreateFieldTrial("WebUSBBlocklist", "TestGroup");
+    // Refresh the blocklist based on the new field trial.
+    list_.ResetToDefaultValuesForTest();
+  }
+
+  EXPECT_TRUE(list_.IsExcluded({0x18D1, 0x58F0, 0x1BAD}));
+  EXPECT_FALSE(list_.IsExcluded({0x18D1, 0x58F0, 0x0100}));
+}