Add missing built-in properties. Resolve properties on import paths. Resolve \ with...

[mono.git] / mcs / class / Microsoft.Build / Microsoft.Build.Evaluation / Project.cs

//
// Project.cs
//
// Author:
//   Leszek Ciesielski (skolima@gmail.com)
//   Rolf Bjarne Kvinge (rolf@xamarin.com)
//   Atsushi Enomoto (atsushi@xamarin.com)
//
// (C) 2011 Leszek Ciesielski
// Copyright (C) 2011,2013 Xamarin Inc. (http://www.xamarin.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Text;
using System.Xml;
using Microsoft.Build.Construction;
using Microsoft.Build.Exceptions;
using Microsoft.Build.Execution;
using Microsoft.Build.Framework;
using Microsoft.Build.Internal;
using Microsoft.Build.Logging;
using System.Collections;

// Basically there are two semantic Project object models and their relationship is not obvious
// (apart from Microsoft.Build.Construction.ProjectRootElement which is a "construction rule").
//
// Microsoft.Build.Evaluation.Project holds some "editable" project model, and it supports
// detailed loader API (such as Items and AllEvaluatedItems).
// ProjectPoperty holds UnevaluatedValue and gives EvaluatedValue too.
//
// Microsoft.Build.Execution.ProjectInstance holds "snapshot" of a project, and it lacks
// detailed loader API. It does not give us Unevaluated property value.
// On the other hand, it supports Targets object model. What Microsoft.Build.Evaluation.Project
// offers there is actually a list of Microsoft.Build.Execution.ProjectInstance objects.
// It should be also noted that only ProjectInstance has Evaluate() method (Project doesn't).
//
// And both API holds different set of descendant types for each and cannot really share the
// loader code. That is lame.
//
// So, can either of them be used to construct the other model? Both API models share the same
// "governor", which is Microsoft.Build.Evaluation.ProjectCollection/ Project is added to
// its LoadedProjects list, while ProjectInstance isn't. Project cannot be loaded to load
// a ProjectInstance, at least within the same ProjectCollection.
//
// On the other hand, can ProjectInstance be used to load a Project? Maybe. Since Project and
// its descendants need Microsoft.Build.Construction.ProjectElement family as its API model
// is part of the public API. Then I still have to understand how those AllEvaluatedItems/
// AllEvaluatedProperties members make sense. EvaluationCounter is another propery in question.

namespace Microsoft.Build.Evaluation
{
        [DebuggerDisplay ("{FullPath} EffectiveToolsVersion={ToolsVersion} #GlobalProperties="
        + "{data.globalProperties.Count} #Properties={data.Properties.Count} #ItemTypes="
        + "{data.ItemTypes.Count} #ItemDefinitions={data.ItemDefinitions.Count} #Items="
        + "{data.Items.Count} #Targets={data.Targets.Count}")]
        public class Project
        {
                public Project (XmlReader xml)
                        : this (ProjectRootElement.Create (xml))
                {
                }

                public Project (XmlReader xml, IDictionary<string, string> globalProperties,
                                              string toolsVersion)
                        : this (ProjectRootElement.Create (xml), globalProperties, toolsVersion)
                {
                }

                public Project (XmlReader xml, IDictionary<string, string> globalProperties,
                                              string toolsVersion, ProjectCollection projectCollection)
                        : this (ProjectRootElement.Create (xml), globalProperties, toolsVersion, projectCollection)
                {
                }

                public Project (XmlReader xml, IDictionary<string, string> globalProperties,
                                              string toolsVersion, ProjectCollection projectCollection,
                                              ProjectLoadSettings loadSettings)
                        : this (ProjectRootElement.Create (xml), globalProperties, toolsVersion, projectCollection, loadSettings)
                {
                }

                public Project (ProjectRootElement xml) : this (xml, null, null)
                {
                }

                public Project (ProjectRootElement xml, IDictionary<string, string> globalProperties,
                                              string toolsVersion)
                        : this (xml, globalProperties, toolsVersion, ProjectCollection.GlobalProjectCollection)
                {
                }

                public Project (ProjectRootElement xml, IDictionary<string, string> globalProperties,
                                              string toolsVersion, ProjectCollection projectCollection)
                        : this (xml, globalProperties, toolsVersion, projectCollection, ProjectLoadSettings.Default)
                {
                }

                public Project (ProjectRootElement xml, IDictionary<string, string> globalProperties,
                                              string toolsVersion, ProjectCollection projectCollection,
                                              ProjectLoadSettings loadSettings)
                {
                        if (projectCollection == null)
                                throw new ArgumentNullException ("projectCollection");
                        this.Xml = xml;
                        this.GlobalProperties = globalProperties ?? new Dictionary<string, string> ();
                        this.ToolsVersion = toolsVersion;
                        this.ProjectCollection = projectCollection;
                        this.load_settings = loadSettings;

                        Initialize (null);
                }
                
                Project (ProjectRootElement imported, Project parent)
                {
                        this.Xml = imported;
                        this.GlobalProperties = parent.GlobalProperties;
                        this.ToolsVersion = parent.ToolsVersion;
                        this.ProjectCollection = parent.ProjectCollection;
                        this.load_settings = parent.load_settings;

                        Initialize (parent);
                }

                public Project (string projectFile)
                        : this (projectFile, null, null)
                {
                }

                public Project (string projectFile, IDictionary<string, string> globalProperties,
                                string toolsVersion)
                : this (projectFile, globalProperties, toolsVersion, ProjectCollection.GlobalProjectCollection, ProjectLoadSettings.Default)
                {
                }

                public Project (string projectFile, IDictionary<string, string> globalProperties,
                                string toolsVersion, ProjectCollection projectCollection)
                : this (projectFile, globalProperties, toolsVersion, projectCollection, ProjectLoadSettings.Default)
                {
                }

                public Project (string projectFile, IDictionary<string, string> globalProperties,
                                string toolsVersion, ProjectCollection projectCollection,
                                ProjectLoadSettings loadSettings)
                        : this (ProjectRootElement.Create (projectFile), globalProperties, toolsVersion, projectCollection, loadSettings)
                {
                }

                ProjectLoadSettings load_settings;

                public IDictionary<string, string> GlobalProperties { get; private set; }

                public ProjectCollection ProjectCollection { get; private set; }

                public string ToolsVersion { get; private set; }

                public ProjectRootElement Xml { get; private set; }

                string dir_path;
                Dictionary<string, ProjectItemDefinition> item_definitions;
                List<ResolvedImport> raw_imports;
                List<ProjectItem> raw_items;
                List<ProjectItem> all_evaluated_items;
                List<ProjectProperty> properties;
                Dictionary<string, ProjectTargetInstance> targets;

                void Initialize (Project parent)
                {
                        dir_path = Directory.GetCurrentDirectory ();
                        raw_imports = new List<ResolvedImport> ();
                        item_definitions = new Dictionary<string, ProjectItemDefinition> ();
                        targets = new Dictionary<string, ProjectTargetInstance> ();
                        raw_items = new List<ProjectItem> ();
                        
                        // FIXME: this is likely hack. Test ImportedProject.Properties to see what exactly should happen.
                        if (parent != null) {
                                properties = parent.properties;
                        } else {
                                properties = new List<ProjectProperty> ();
                        
                                foreach (DictionaryEntry p in Environment.GetEnvironmentVariables ())
                                        this.properties.Add (new EnvironmentProjectProperty (this, (string)p.Key, (string)p.Value));
                                foreach (var p in GlobalProperties)
                                        this.properties.Add (new GlobalProjectProperty (this, p.Key, p.Value));
                                var tools = ProjectCollection.GetToolset (this.ToolsVersion) ?? ProjectCollection.GetToolset (this.ProjectCollection.DefaultToolsVersion);
                                foreach (var p in ProjectCollection.GetReservedProperties (tools, this))
                                        this.properties.Add (p);
                                foreach (var p in ProjectCollection.GetWellKnownProperties (this))
                                        this.properties.Add (p);
                        }

                        ProcessXml (parent);
                        
                        ProjectCollection.AddProject (this);
                }
                
                static readonly char [] item_sep = {';'};
                
                void ProcessXml (Project parent)
                {
                        // this needs to be initialized here (regardless of that items won't be evaluated at property evaluation;
                        // Conditions could incorrectly reference items and lack of this list causes NRE.
                        all_evaluated_items = new List<ProjectItem> ();

                        // property evaluation happens couple of times.
                        // At first step, all non-imported properties are evaluated TOO, WHILE those properties are being evaluated.
                        // This means, Include and IncludeGroup elements with Condition attribute MAY contain references to
                        // properties and they will be expanded.
                        var elements = EvaluatePropertiesAndImports (Xml.Children).ToArray (); // ToArray(): to not lazily evaluate elements.
                        
                        // next, evaluate items
                        EvaluateItems (elements);
                        
                        // finally, evaluate targets and tasks
                        EvaluateTasks (elements);
                }
                
                IEnumerable<ProjectElement> EvaluatePropertiesAndImports (IEnumerable<ProjectElement> elements)
                {
                        // First step: evaluate Properties
                        foreach (var child in elements) {
                                yield return child;
                                var pge = child as ProjectPropertyGroupElement;
                                if (pge != null && Evaluate (pge.Condition))
                                        foreach (var p in pge.Properties)
                                                // do not allow overwriting reserved or well-known properties by user
                                                if (!this.properties.Any (_ => (_.IsReservedProperty || _.IsWellKnownProperty) && _.Name.Equals (p.Name, StringComparison.InvariantCultureIgnoreCase)))
                                                        if (Evaluate (p.Condition))
                                                                this.properties.Add (new XmlProjectProperty (this, p, PropertyType.Normal, ProjectCollection.OngoingImports.Any ()));

                                var ige = child as ProjectImportGroupElement;
                                if (ige != null && Evaluate (ige.Condition)) {
                                        foreach (var incc in ige.Imports) {
                                                foreach (var e in Import (incc))
                                                        yield return e;
                                        }
                                }
                                var inc = child as ProjectImportElement;
                                if (inc != null && Evaluate (inc.Condition))
                                        foreach (var e in Import (inc))
                                                yield return e;
                        }
                }

                void EvaluateItems (IEnumerable<ProjectElement> elements)
                {
                        foreach (var child in elements) {
                                var ige = child as ProjectItemGroupElement;
                                if (ige != null) {
                                        foreach (var p in ige.Items) {
                                                if (!Evaluate (ige.Condition) || !Evaluate (p.Condition))
                                                        continue;
                                                var includes = ExpandString (p.Include).Split (item_sep, StringSplitOptions.RemoveEmptyEntries);
                                                var excludes = ExpandString (p.Exclude).Split (item_sep, StringSplitOptions.RemoveEmptyEntries);
                                                
                                                if (includes.Length == 0)
                                                        continue;                                               
                                                if (includes.Length == 1 && includes [0].IndexOf ('*') < 0 && excludes.Length == 0) {
                                                        // for most case - shortcut.
                                                        var item = new ProjectItem (this, p, includes [0]);
                                                        this.raw_items.Add (item);
                                                        all_evaluated_items.Add (item);
                                                } else {
                                                        var ds = new Microsoft.Build.BuildEngine.DirectoryScanner () {
                                                                BaseDirectory = new DirectoryInfo (DirectoryPath),
                                                                Includes = includes.Select (i => new ProjectTaskItem (p, i)).ToArray (),
                                                                Excludes = excludes.Select (e => new ProjectTaskItem (p, e)).ToArray (),
                                                        };
                                                        ds.Scan ();
                                                        foreach (var taskItem in ds.MatchedItems) {
                                                                if (all_evaluated_items.Any (i => i.EvaluatedInclude == taskItem.ItemSpec && i.ItemType == p.ItemType))
                                                                        continue; // skip duplicate
                                                                var item = new ProjectItem (this, p, taskItem.ItemSpec);
                                                                string recurse = taskItem.GetMetadata ("RecursiveDir");
                                                                if (!string.IsNullOrEmpty (recurse))
                                                                        item.RecursiveDir = recurse;
                                                                this.raw_items.Add (item);
                                                                all_evaluated_items.Add (item);
                                                        }
                                                }
                                        }
                                }
                                var def = child as ProjectItemDefinitionGroupElement;
                                if (def != null) {
                                        foreach (var p in def.ItemDefinitions) {
                                                if (Evaluate (p.Condition)) {
                                                        ProjectItemDefinition existing;
                                                        if (!item_definitions.TryGetValue (p.ItemType, out existing))
                                                                item_definitions.Add (p.ItemType, (existing = new ProjectItemDefinition (this, p.ItemType)));
                                                        existing.AddItems (p);
                                                }
                                        }
                                }
                        }
                        all_evaluated_items.Sort ((p1, p2) => string.Compare (p1.ItemType, p2.ItemType, StringComparison.OrdinalIgnoreCase));
                }
                
                void EvaluateTasks (IEnumerable<ProjectElement> elements)
                {
                        foreach (var child in elements) {
                                var te = child as ProjectTargetElement;
                                if (te != null)
                                        this.targets.Add (te.Name, new ProjectTargetInstance (te));
                        }
                }
                
                IEnumerable<ProjectElement> Import (ProjectImportElement import)
                {
                        string dir = ProjectCollection.GetEvaluationTimeThisFileDirectory (() => FullPath);
                        string path = ExpandString (import.Project);
                        path = Path.IsPathRooted (path) ? path : dir != null ? Path.Combine (dir, path) : Path.GetFullPath (path);
                        if (ProjectCollection.OngoingImports.Contains (path)) {
                                switch (load_settings) {
                                case ProjectLoadSettings.RejectCircularImports:
                                        throw new InvalidProjectFileException (import.Location, null, string.Format ("Circular imports was detected: {0} (resolved as \"{1}\") is already on \"importing\" stack", import.Project, path));
                                }
                                return new ProjectElement [0]; // do not import circular references
                        }
                        ProjectCollection.OngoingImports.Push (path);
                        try {
                                using (var reader = XmlReader.Create (WindowsCompatibilityExtensions.NormalizeFilePath (path))) {
                                        var root = ProjectRootElement.Create (reader, ProjectCollection);
                                        raw_imports.Add (new ResolvedImport (import, root, true));
                                        return this.EvaluatePropertiesAndImports (root.Children).ToArray ();
                                }
                        } finally {
                                ProjectCollection.OngoingImports.Pop ();
                        }
                }

                public ICollection<ProjectItem> GetItemsIgnoringCondition (string itemType)
                {
                        return new CollectionFromEnumerable<ProjectItem> (raw_items.Where (p => p.ItemType.Equals (itemType, StringComparison.OrdinalIgnoreCase)));
                }

                public void RemoveItems (IEnumerable<ProjectItem> items)
                {
                        var removal = new List<ProjectItem> (items);
                        foreach (var item in removal) {
                                var parent = item.Xml.Parent;
                                parent.RemoveChild (item.Xml);
                                if (parent.Count == 0)
                                        parent.Parent.RemoveChild (parent);
                        }
                }

                static readonly Dictionary<string, string> empty_metadata = new Dictionary<string, string> ();

                public IList<ProjectItem> AddItem (string itemType, string unevaluatedInclude)
                {
                        return AddItem (itemType, unevaluatedInclude, empty_metadata);
                }

                public IList<ProjectItem> AddItem (string itemType, string unevaluatedInclude,
                                IEnumerable<KeyValuePair<string, string>> metadata)
                {
                        // FIXME: needs several check that AddItemFast() does not process (see MSDN for details).

                        return AddItemFast (itemType, unevaluatedInclude, metadata);
                }

                public IList<ProjectItem> AddItemFast (string itemType, string unevaluatedInclude)
                {
                        return AddItemFast (itemType, unevaluatedInclude, empty_metadata);
                }

                public IList<ProjectItem> AddItemFast (string itemType, string unevaluatedInclude,
                                                                     IEnumerable<KeyValuePair<string, string>> metadata)
                {
                        throw new NotImplementedException ();
                }
                
                static readonly char [] target_sep = new char[] {';'};

                public bool Build ()
                {
                        return Build (Xml.DefaultTargets.Split (target_sep, StringSplitOptions.RemoveEmptyEntries));
                }

                public bool Build (IEnumerable<ILogger> loggers)
                {
                        return Build (Xml.DefaultTargets.Split (target_sep, StringSplitOptions.RemoveEmptyEntries), loggers);
                }

                public bool Build (string target)
                {
                        return string.IsNullOrWhiteSpace (target) ? Build () : Build (new string [] {target});
                }

                public bool Build (string[] targets)
                {
                        return Build (targets, new ILogger [0]);
                }

                public bool Build (ILogger logger)
                {
                        return Build (Xml.DefaultTargets.Split (target_sep, StringSplitOptions.RemoveEmptyEntries), new ILogger [] {logger});
                }

                public bool Build (string[] targets, IEnumerable<ILogger> loggers)
                {
                        return Build (targets, loggers, new ForwardingLoggerRecord [0]);
                }

                public bool Build (IEnumerable<ILogger> loggers, IEnumerable<ForwardingLoggerRecord> remoteLoggers)
                {
                        return Build (Xml.DefaultTargets.Split (target_sep, StringSplitOptions.RemoveEmptyEntries), loggers, remoteLoggers);
                }

                public bool Build (string target, IEnumerable<ILogger> loggers)
                {
                        return Build (new string [] { target }, loggers);
                }

                public bool Build (string[] targets, IEnumerable<ILogger> loggers, IEnumerable<ForwardingLoggerRecord> remoteLoggers)
                {
                        // Unlike ProjectInstance.Build(), there is no place to fill outputs by targets, so ignore them
                        // (i.e. we don't use the overload with output).
                        //
                        // This does not check FullPath, so don't call GetProjectInstanceForBuild() directly.
                        return new BuildManager ().GetProjectInstanceForBuildInternal (this).Build (targets, loggers, remoteLoggers);
                }

                public bool Build (string target, IEnumerable<ILogger> loggers, IEnumerable<ForwardingLoggerRecord> remoteLoggers)
                {
                        return Build (new string [] { target }, loggers, remoteLoggers);
                }

                public ProjectInstance CreateProjectInstance ()
                {
                        var ret = new ProjectInstance (Xml, GlobalProperties, ToolsVersion, ProjectCollection);
                        // FIXME: maybe fill other properties to the result.
                        return ret;
                }
                
                bool Evaluate (string unexpandedValue)
                {
                        return string.IsNullOrWhiteSpace (unexpandedValue) || new ExpressionEvaluator (this, null).EvaluateAsBoolean (unexpandedValue);
                }

                public string ExpandString (string unexpandedValue)
                {
                        return ExpandString (unexpandedValue, null);
                }
                
                string ExpandString (string unexpandedValue, string replacementForMissingStuff)
                {
                        return new ExpressionEvaluator (this, replacementForMissingStuff).Evaluate (unexpandedValue);
                }

                public static string GetEvaluatedItemIncludeEscaped (ProjectItem item)
                {
                        return ProjectCollection.Escape (item.EvaluatedInclude);
                }

                public static string GetEvaluatedItemIncludeEscaped (ProjectItemDefinition item)
                {
                        // ?? ItemDefinition does not have Include attribute. What's the point here?
                        throw new NotImplementedException ();
                }

                public ICollection<ProjectItem> GetItems (string itemType)
                {
                        return new CollectionFromEnumerable<ProjectItem> (Items.Where (p => p.ItemType.Equals (itemType, StringComparison.OrdinalIgnoreCase)));
                }

                public ICollection<ProjectItem> GetItemsByEvaluatedInclude (string evaluatedInclude)
                {
                        return new CollectionFromEnumerable<ProjectItem> (Items.Where (p => p.EvaluatedInclude.Equals (evaluatedInclude, StringComparison.OrdinalIgnoreCase)));
                }

                public IEnumerable<ProjectElement> GetLogicalProject ()
                {
                        throw new NotImplementedException ();
                }

                public static string GetMetadataValueEscaped (ProjectMetadata metadatum)
                {
                        return ProjectCollection.Escape (metadatum.EvaluatedValue);
                }

                public static string GetMetadataValueEscaped (ProjectItem item, string name)
                {
                        var md = item.GetMetadata (name);
                        return md != null ? ProjectCollection.Escape (md.EvaluatedValue) : null;
                }

                public static string GetMetadataValueEscaped (ProjectItemDefinition item, string name)
                {
                        var md = item.Metadata.FirstOrDefault (m => m.Name == name);
                        return md != null ? ProjectCollection.Escape (md.EvaluatedValue) : null;
                }

                public string GetPropertyValue (string name)
                {
                        var prop = GetProperty (name);
                        return prop != null ? prop.EvaluatedValue : string.Empty;
                }

                public static string GetPropertyValueEscaped (ProjectProperty property)
                {
                        // WTF happens here.
                        return property.EvaluatedValue;
                }

                public ProjectProperty GetProperty (string name)
                {
                        return properties.FirstOrDefault (p => p.Name.Equals (name, StringComparison.OrdinalIgnoreCase));
                }

                public void MarkDirty ()
                {
                        if (!DisableMarkDirty)
                                is_dirty = true;
                }

                public void ReevaluateIfNecessary ()
                {
                        throw new NotImplementedException ();
                }

                public bool RemoveGlobalProperty (string name)
                {
                        throw new NotImplementedException ();
                }

                public bool RemoveItem (ProjectItem item)
                {
                        throw new NotImplementedException ();
                }

                public bool RemoveProperty (ProjectProperty property)
                {
                        var removed = properties.FirstOrDefault (p => p.Name.Equals (property.Name, StringComparison.OrdinalIgnoreCase));
                        if (removed == null)
                                return false;
                        properties.Remove (removed);
                        return true;
                }

                public void Save ()
                {
                        Xml.Save ();
                }

                public void Save (TextWriter writer)
                {
                        Xml.Save (writer);
                }

                public void Save (string path)
                {
                        Save (path, Encoding.Default);
                }

                public void Save (Encoding encoding)
                {
                        Save (FullPath, encoding);
                }

                public void Save (string path, Encoding encoding)
                {
                        using (var writer = new StreamWriter (path, false, encoding))
                                Save (writer);
                }

                public void SaveLogicalProject (TextWriter writer)
                {
                        throw new NotImplementedException ();
                }

                public bool SetGlobalProperty (string name, string escapedValue)
                {
                        throw new NotImplementedException ();
                }

                public ProjectProperty SetProperty (string name, string unevaluatedValue)
                {
                        var p = new ManuallyAddedProjectProperty (this, name, unevaluatedValue);
                        properties.Add (p);
                        return p;
                }

                public ICollection<ProjectMetadata> AllEvaluatedItemDefinitionMetadata {
                        get { throw new NotImplementedException (); }
                }

                public ICollection<ProjectItem> AllEvaluatedItems {
                        get { return all_evaluated_items; }
                }

                public ICollection<ProjectProperty> AllEvaluatedProperties {
                        get { return properties; }
                }

                public IDictionary<string, List<string>> ConditionedProperties {
                        get {
                                // this property returns different instances every time.
                                var dic = new Dictionary<string, List<string>> ();
                                
                                // but I dunno HOW this evaluates
                                
                                throw new NotImplementedException ();
                        }
                }

                public string DirectoryPath {
                        get { return dir_path; }
                }

                public bool DisableMarkDirty { get; set; }

                public int EvaluationCounter {
                        get { throw new NotImplementedException (); }
                }

                public string FullPath {
                        get { return Xml.FullPath; }
                        set { Xml.FullPath = value; }
                }
                
                class ResolvedImportComparer : IEqualityComparer<ResolvedImport>
                {
                        public static ResolvedImportComparer Instance = new ResolvedImportComparer ();
                        
                        public bool Equals (ResolvedImport x, ResolvedImport y)
                        {
                                return x.ImportedProject.FullPath.Equals (y.ImportedProject.FullPath);
                        }
                        public int GetHashCode (ResolvedImport obj)
                        {
                                return obj.ImportedProject.FullPath.GetHashCode ();
                        }
                }

                public IList<ResolvedImport> Imports {
                        get { return raw_imports.Distinct (ResolvedImportComparer.Instance).ToList (); }
                }

                public IList<ResolvedImport> ImportsIncludingDuplicates {
                        get { return raw_imports; }
                }

                public bool IsBuildEnabled {
                        get { return ProjectCollection.IsBuildEnabled; }
                }

                bool is_dirty;
                public bool IsDirty {
                        get { return is_dirty; }
                }

                public IDictionary<string, ProjectItemDefinition> ItemDefinitions {
                        get { return item_definitions; }
                }

                [MonoTODO ("should be different from AllEvaluatedItems")]
                public ICollection<ProjectItem> Items {
                        get { return AllEvaluatedItems; }
                }

                public ICollection<ProjectItem> ItemsIgnoringCondition {
                        get { return raw_items; }
                }

                public ICollection<string> ItemTypes {
                        get { return new CollectionFromEnumerable<string> (raw_items.Select (i => i.ItemType).Distinct ()); }
                }

                [MonoTODO ("should be different from AllEvaluatedProperties")]
                public ICollection<ProjectProperty> Properties {
                        get { return AllEvaluatedProperties; }
                }

                public bool SkipEvaluation { get; set; }

                #if NET_4_5
                public
                #else
                internal
                #endif
                IDictionary<string, ProjectTargetInstance> Targets {
                        get { return targets; }
                }
                
                // These are required for reserved property, represents dynamically changing property values.
                // This should resolve to either the project file path or that of the imported file.
                internal string GetEvaluationTimeThisFileDirectory ()
                {
                        var file = GetEvaluationTimeThisFile ();
                        var dir = Path.IsPathRooted (file) ? Path.GetDirectoryName (file) : Directory.GetCurrentDirectory ();
                        return dir + Path.DirectorySeparatorChar;
                }

                internal string GetEvaluationTimeThisFile ()
                {
                        return ProjectCollection.OngoingImports.Count > 0 ? ProjectCollection.OngoingImports.Peek () : FullPath ?? string.Empty;
                }
                
                internal string GetFullPath (string pathRelativeToProject)
                {
                        if (Path.IsPathRooted (pathRelativeToProject))
                                return pathRelativeToProject;
                        return Path.GetFullPath (Path.Combine (DirectoryPath, pathRelativeToProject));
                }
        }
}