public void TryGetValue_ReferenceNotFound()
        {
            var dictionary = new WeakValueDictionary <string, string>();

            string v;
            bool   result = dictionary.TryGetValue("x", out v);

            Assert.IsFalse(result);
            Assert.IsNull(v);
            Assert.IsFalse(dictionary.Contains("x"));
        }
        public void Indexer_ReferenceFound()
        {
            string k1 = "key";
            string v1 = "value";

            var dictionary = new WeakValueDictionary<string, string>();
            dictionary[k1] = v1;

            // Now look for the same key we inserted
            string v2 = dictionary[k1];

            Assertion.AssertEquals(true, Object.ReferenceEquals(v1, v2));
            Assertion.AssertEquals(true, dictionary.Contains(k1));
        }
        public void Indexer_ReferenceFound()
        {
            string k1 = "key";
            string v1 = "value";

            var dictionary = new WeakValueDictionary <string, string>();

            dictionary[k1] = v1;

            // Now look for the same key we inserted
            string v2 = dictionary[k1];

            Assertion.AssertEquals(true, Object.ReferenceEquals(v1, v2));
            Assertion.AssertEquals(true, dictionary.Contains(k1));
        }
        public void Indexer_NullValue_ReferenceFound()
        {
            string k1 = "key";
            string v1 = null;

            var dictionary = new WeakValueDictionary<string, string>();
            dictionary[k1] = v1;

            // Now look for the same key we inserted
            string v2 = dictionary[k1];

            Assertion.AssertEquals(true, Object.ReferenceEquals(v1, v2));
            Assertion.AssertEquals(true, dictionary.Contains(k1));

            // Should not scavenge values that are null, rather than collected
            dictionary.Scavenge();
            Assertion.AssertEquals(1, dictionary.Count);
        }
        public void Indexer_NullValue_ReferenceFound()
        {
            string k1 = "key";
            string v1 = null;

            var dictionary = new WeakValueDictionary <string, string>();

            dictionary[k1] = v1;

            // Now look for the same key we inserted
            string v2 = dictionary[k1];

            Assertion.AssertEquals(true, Object.ReferenceEquals(v1, v2));
            Assertion.AssertEquals(true, dictionary.Contains(k1));

            // Should not scavenge values that are null, rather than collected
            dictionary.Scavenge();
            Assertion.AssertEquals(1, dictionary.Count);
        }
Example #6
0
        /// <summary>
        /// Returns an existing ProjectRootElement for the specified file path, if any.
        /// If none exists, calls the provided delegate to load one, and adds that to the cache.
        /// The reason that it calls back to do this is so that the cache is locked between determining
        /// that the entry does not exist and adding the entry.
        ///
        /// If <see cref="_autoReloadFromDisk"/> was set to true, and the file on disk has changed since it was cached,
        /// it will be reloaded before being returned.
        ///
        /// Thread safe.
        /// </summary>
        /// <remarks>
        /// Never needs to consult the strong cache as well, since if the item is in there, it will
        /// not have left the weak cache.
        /// If item is found, boosts it to the top of the strong cache.
        /// </remarks>
        /// <param name="projectFile">The project file which contains the ProjectRootElement.  Must be a full path.</param>
        /// <param name="openProjectRootElement">The delegate to use to load if necessary. May be null.</param>
        /// <param name="isExplicitlyLoaded"><code>true</code> if the project is explicitly loaded, otherwise <code>false</code>.</param>
        /// <param name="preserveFormatting"><code>true</code> to the project was loaded with the formated preserved, otherwise <code>false</code>.</param>
        /// <returns>The ProjectRootElement instance if one exists.  Null otherwise.</returns>
        internal override ProjectRootElement Get(string projectFile, OpenProjectRootElement openProjectRootElement, bool isExplicitlyLoaded,
                                                 bool?preserveFormatting)
        {
            // Should already have been canonicalized
            ErrorUtilities.VerifyThrowInternalRooted(projectFile);

            lock (_locker)
            {
                ProjectRootElement projectRootElement;
                _weakCache.TryGetValue(projectFile, out projectRootElement);

                if (preserveFormatting != null && projectRootElement != null && projectRootElement.XmlDocument.PreserveWhitespace != preserveFormatting)
                {
                    //  Cached project doesn't match preserveFormatting setting, so reload it
                    projectRootElement.Reload(true, preserveFormatting);
                }

                if (projectRootElement != null && _autoReloadFromDisk)
                {
                    FileInfo fileInfo = FileUtilities.GetFileInfoNoThrow(projectFile);

                    // If the file doesn't exist on disk, go ahead and use the cached version.
                    // It's an in-memory project that hasn't been saved yet.
                    if (fileInfo != null)
                    {
                        bool forgetEntry = false;

                        if (fileInfo.LastWriteTime != projectRootElement.LastWriteTimeWhenRead)
                        {
                            // File was changed on disk by external means. Cached version is no longer reliable.
                            // We could throw here or ignore the problem, but it is a common and reasonable pattern to change a file
                            // externally and load a new project over it to see the new content. So we dump it from the cache
                            // to force a load from disk. There might then exist more than one ProjectRootElement with the same path,
                            // but clients ought not get themselves into such a state - and unless they save them to disk,
                            // it may not be a problem.
                            forgetEntry = true;
                        }
                        else if (!String.IsNullOrEmpty(Environment.GetEnvironmentVariable("MSBUILDCACHECHECKFILECONTENT")))
                        {
                            // QA tests run too fast for the timestamp check to work. This environment variable is for their
                            // use: it checks the file content as well as the timestamp. That's better than completely disabling
                            // the cache as we get test coverage of the rest of the cache code.
                            XmlDocument document = new XmlDocument();
                            document.PreserveWhitespace = projectRootElement.XmlDocument.PreserveWhitespace;

                            using (var xtr = XmlReaderExtension.Create(projectRootElement.FullPath, projectRootElement.ProjectRootElementCache.LoadProjectsReadOnly))
                            {
                                document.Load(xtr.Reader);
                            }

                            string diskContent  = document.OuterXml;
                            string cacheContent = projectRootElement.XmlDocument.OuterXml;

                            if (diskContent != cacheContent)
                            {
                                forgetEntry = true;
                            }
                        }

                        if (forgetEntry)
                        {
                            ForgetEntry(projectRootElement);

                            DebugTraceCache("Out of date dropped from XML cache: ", projectFile);
                            projectRootElement = null;
                        }
                    }
                }

                if (projectRootElement == null && openProjectRootElement != null)
                {
                    projectRootElement = openProjectRootElement(projectFile, this);

                    ErrorUtilities.VerifyThrowInternalNull(projectRootElement, "projectRootElement");
                    ErrorUtilities.VerifyThrow(projectRootElement.FullPath == projectFile, "Got project back with incorrect path");
                    ErrorUtilities.VerifyThrow(_weakCache.Contains(projectFile), "Open should have renamed into cache and boosted");
                }
                else if (projectRootElement != null)
                {
                    DebugTraceCache("Satisfied from XML cache: ", projectFile);
                    BoostEntryInStrongCache(projectRootElement);
                }

                // An implicit load will never reset the explicit flag.
                if (projectRootElement != null && isExplicitlyLoaded)
                {
                    projectRootElement.MarkAsExplicitlyLoaded();
                }

                return(projectRootElement);
            }
        }
        public void TryGetValue_ReferenceNotFound()
        {
            var dictionary = new WeakValueDictionary<string, string>();

            string v;
            bool result = dictionary.TryGetValue("x", out v);

            Assert.IsFalse(result);
            Assert.IsNull(v);
            Assert.IsFalse(dictionary.Contains("x"));
        }