Add initial prototype for the GN meta-buildsystem.

tools/gn/pattern_unittest.cc

+// Copyright (c) 2013 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 "testing/gtest/include/gtest/gtest.h"
+#include "tools/gn/pattern.h"
+
+namespace {
+
+struct Case {
+  const char* pattern;
+  const char* candidate;
+  bool expected_match;
+};
+
+}  // namespace
+
+TEST(Pattern, Matches) {
+  Case pattern_cases[] = {
+    // Empty pattern matches only empty string.
+    { "", "", true },
+    { "", "foo", false },
+    // Exact matches.
+    { "foo", "foo", true },
+    { "foo", "bar", false },
+    // Path boundaries.
+    { "\\b", "", true },
+    { "\\b", "/", true },
+    { "\\b\\b", "/", true },
+    { "\\b\\b\\b", "", false },
+    { "\\b\\b\\b", "/", true },
+    { "\\b", "//", false },
+    { "\\bfoo\\b", "foo", true },
+    { "\\bfoo\\b", "/foo/", true },
+    { "\\b\\bfoo", "/foo", true },
+    // *
+    { "*", "", true },
+    { "*", "foo", true },
+    { "*foo", "foo", true },
+    { "*foo", "gagafoo", true },
+    { "*foo", "gagafoob", false },
+    { "foo*bar", "foobar", true },
+    { "foo*bar", "foo-bar", true },
+    { "foo*bar", "foolalalalabar", true },
+    { "foo*bar", "foolalalalabaz", false },
+    { "*a*b*c*d*", "abcd", true },
+    { "*a*b*c*d*", "1a2b3c4d5", true },
+    { "*a*b*c*d*", "1a2b3c45", false },
+    { "*\\bfoo\\b*", "foo", true },
+    { "*\\bfoo\\b*", "/foo/", true },
+    { "*\\bfoo\\b*", "foob", false },
+    { "*\\bfoo\\b*", "lala/foo/bar/baz", true },
+  };
+  for (size_t i = 0; i < arraysize(pattern_cases); i++) {
+    const Case& c = pattern_cases[i];
+    Pattern pattern(c.pattern);
+    bool result = pattern.MatchesString(c.candidate);
+    EXPECT_EQ(c.expected_match, result) << i << ": \"" << c.pattern
+        << "\", \"" << c.candidate << "\"";
+  }
+}