Use lock on BuildManager for TryBuild(), add TryGetPropertyValue(), and add TryGetItems()

src/MSBuildProjectCreator.UnitTests/ItemTests.cs

@@ -5,6 +5,7 @@
 using Microsoft.Build.Evaluation;
 using Shouldly;
 using System.Collections.Generic;
+using System.Linq;
 using Xunit;
 
 namespace Microsoft.Build.Utilities.ProjectCreation.UnitTests
@@ -292,6 +293,54 @@ public void RemoveItem()
                     StringCompareShould.IgnoreLineEndings);
         }
 
+        [Fact]
+        public void TryGetItemsCustomSelector()
+        {
+            ProjectCreator.Create(projectFileOptions: NewProjectFileOptions.None)
+                .ItemInclude("MyItem", "3F114C1509CF4D499A44F986BEBD5707")
+                .ItemInclude("MyItem", "8A9654A639F5429AB1C7A8F2AE9639D8")
+                .TryGetItems("MyItem", i => i.EvaluatedInclude, out IReadOnlyCollection<string> items);
+
+            items.ShouldBe(new List<string>
+            {
+                "3F114C1509CF4D499A44F986BEBD5707",
+                "8A9654A639F5429AB1C7A8F2AE9639D8"
+            });
+        }
+
+        [Fact]
+        public void TryGetItemsDictionary()
+        {
+            ProjectCreator.Create(projectFileOptions: NewProjectFileOptions.None)
+                .ItemInclude("MyItem", "A9AA54F5E51E4C0A966A5F5CDBD5EC9D", metadata: new Dictionary<string, string> { ["MyMetadata"] = "A3A33B3B55A841D883A05F6CA920AC1F" })
+                .ItemInclude("MyItem", "910E2DA9075043AA850D923E8E3EE398", metadata: new Dictionary<string, string> { ["MyMetadata"] = "EF8E0862B0A946D98DA7082E70AEC3E9" })
+                .TryGetItems("MyItem", "MyMetadata", out IReadOnlyDictionary<string, string> items);
+
+            items.ShouldBe(new Dictionary<string, string>
+            {
+                ["A9AA54F5E51E4C0A966A5F5CDBD5EC9D"] = "A3A33B3B55A841D883A05F6CA920AC1F",
+                ["910E2DA9075043AA850D923E8E3EE398"] = "EF8E0862B0A946D98DA7082E70AEC3E9"
+            });
+        }
+
+        [Fact]
+        public void TryGetItemsProjectItems()
+        {
+            ProjectCreator.Create(projectFileOptions: NewProjectFileOptions.None)
+                .ItemInclude("MyItem", "B39E047FC97A48E3964EEA70C46F4E35")
+                .ItemInclude("MyItem", "E0FA8DA2551F4EE18D2102149D3049D4")
+                .TryGetItems("MyItem", out IReadOnlyCollection<ProjectItem> items);
+
+            items
+                .Select(i => i.EvaluatedInclude)
+                .ToList()
+                .ShouldBe(new List<string>
+                {
+                    "B39E047FC97A48E3964EEA70C46F4E35",
+                    "E0FA8DA2551F4EE18D2102149D3049D4"
+                });
+        }
+
         [Fact]
         public void UpdateItem()
         {

src/MSBuildProjectCreator.UnitTests/PropertyTests.cs

@@ -93,5 +93,18 @@ public void PropertySimple()
 </Project>",
                     StringCompareShould.IgnoreLineEndings);
         }
+
+        [Fact]
+        public void TryGetPropertyValueSimple()
+        {
+            ProjectCreator.Create(projectFileOptions: NewProjectFileOptions.None)
+                .Property("E7A39154F5AB476A928067251F88FFCE", "E8F579A7E3374F389120CF6D888E74B9")
+                .Property("FAB58E5B32D14990ACE2490D7593FDF6", "60F55FB14D2E44B2BA4EC91488D9FF8F")
+                .TryGetPropertyValue("E7A39154F5AB476A928067251F88FFCE", out string property1)
+                .TryGetPropertyValue("FAB58E5B32D14990ACE2490D7593FDF6", out string property2);
+
+            property1.ShouldBe("E8F579A7E3374F389120CF6D888E74B9");
+            property2.ShouldBe("60F55FB14D2E44B2BA4EC91488D9FF8F");
+        }
     }
 }

src/MSBuildProjectCreator/ProjectCreator.Build.cs

@@ -2,6 +2,8 @@
 //
 // Licensed under the MIT license.
 
+using Microsoft.Build.Execution;
+
 namespace Microsoft.Build.Utilities.ProjectCreation
 {
     public partial class ProjectCreator
@@ -14,7 +16,10 @@ public partial class ProjectCreator
         /// <returns>The current <see cref="ProjectCreator"/>.</returns>
         public ProjectCreator TryBuild(string target, out bool result)
         {
-            result = Project.Build(target);
+            lock (BuildManager.DefaultBuildManager)
+            {
+                result = Project.Build(target);
+            }
 
             return this;
         }
@@ -30,7 +35,10 @@ public ProjectCreator TryBuild(string target, out bool result, out BuildOutput b
         {
             buildOutput = BuildOutput.Create();
 
-            result = Project.Build(target, buildOutput.AsEnumerable());
+            lock (BuildManager.DefaultBuildManager)
+            {
+                result = Project.Build(target, buildOutput.AsEnumerable());
+            }
 
             return this;
         }
@@ -42,7 +50,10 @@ public ProjectCreator TryBuild(string target, out bool result, out BuildOutput b
         /// <returns>The current <see cref="ProjectCreator"/>.</returns>
         public ProjectCreator TryBuild(out bool result)
         {
-            result = Project.Build();
+            lock (BuildManager.DefaultBuildManager)
+            {
+                result = Project.Build();
+            }
 
             return this;
         }
@@ -57,7 +68,10 @@ public ProjectCreator TryBuild(out bool result, out BuildOutput buildOutput)
         {
             buildOutput = BuildOutput.Create();
 
-            result = Project.Build(buildOutput.AsEnumerable());
+            lock (BuildManager.DefaultBuildManager)
+            {
+                result = Project.Build(buildOutput.AsEnumerable());
+            }
 
             return this;
         }

src/MSBuildProjectCreator/ProjectCreator.Items.cs

@@ -4,6 +4,7 @@
 
 using Microsoft.Build.Construction;
 using Microsoft.Build.Evaluation;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 
@@ -314,6 +315,58 @@ public ProjectCreator ItemUpdate(
                         condition: condition);
         }
 
+        /// <summary>
+        /// Gets a list of items in the project.
+        /// </summary>
+        /// <param name="itemType">The item type.</param>
+        /// <param name="items">A <see cref="IReadOnlyCollection{ProjectItem}"/> containing the items.</param>
+        /// <returns>The current <see cref="ProjectCreator"/>.</returns>
+        public ProjectCreator TryGetItems(string itemType, out IReadOnlyCollection<ProjectItem> items)
+        {
+            items = Project.GetItems(itemType).ToList();
+
+            return this;
+        }
+
+        /// <summary>
+        /// Gets a list of items in the project.
+        /// </summary>
+        /// <typeparam name="T">The type of the object that the selector will return.</typeparam>
+        /// <param name="itemType">The item type.</param>
+        /// <param name="selector">A <see cref="Func{ProjectItem, T}"/> that gets the desired return object.</param>
+        /// <param name="items">A <see cref="IReadOnlyCollection{T}"/> containing the items.</param>
+        /// <returns>The current <see cref="ProjectCreator"/>.</returns>
+        public ProjectCreator TryGetItems<T>(string itemType, Func<ProjectItem, T> selector, out IReadOnlyCollection<T> items)
+        {
+            if (selector == null)
+            {
+                throw new ArgumentNullException(nameof(selector));
+            }
+
+            items = Project.GetItems(itemType).Select(selector).ToList();
+
+            return this;
+        }
+
+        /// <summary>
+        /// Gets a list of items in the project.
+        /// </summary>
+        /// <param name="itemType">The item type.</param>
+        /// <param name="metadataName">The name of a metadata item to get.</param>
+        /// <param name="items">A <see cref="IReadOnlyDictionary{String,String}"/> containing the ItemSpec and metadata value.</param>
+        /// <returns>The current <see cref="ProjectCreator"/>.</returns>
+        public ProjectCreator TryGetItems(string itemType, string metadataName, out IReadOnlyDictionary<string, string> items)
+        {
+            if (String.IsNullOrWhiteSpace(metadataName))
+            {
+                throw new ArgumentNullException(nameof(metadataName));
+            }
+
+            items = Project.GetItems(itemType).ToDictionary(i => i.EvaluatedInclude, i => i.GetMetadataValue(metadataName));
+
+            return this;
+        }
+
         /// <summary>
         /// Adds an item to the current item group.
         /// </summary>

src/MSBuildProjectCreator/ProjectCreator.Properties.cs

@@ -24,6 +24,19 @@ public ProjectCreator Property(string name, string unevaluatedValue, string cond
             return Property(LastPropertyGroup, name, unevaluatedValue, condition, setIfEmpty);
         }
 
+        /// <summary>
+        /// Attempts to get the specified evaluated property value.
+        /// </summary>
+        /// <param name="name">The name of the property.</param>
+        /// <param name="value">The evaluated value of the property</param>
+        /// <returns>The unescaped value of the property if it exists, otherwise an empty string.</returns>
+        public ProjectCreator TryGetPropertyValue(string name, out string value)
+        {
+            value = Project.GetPropertyValue(name);
+
+            return this;
+        }
+
         /// <summary>
         /// Adds a property element to the current &lt;PropertyGroup /&gt;.  A property group is automatically added if necessary.  if <paramref name="unevaluatedValue"/> is <code>null</code>, the property is not added.
         /// </summary>