Define BuildNumberFromVersionJson msbuild property

This allows folks who want to do particularly custom things with their versioning stamps to have a bit more data from the version.json file with which to work.

Fixes #115

Author: AArnott

src/NerdBank.GitVersioning.Tests/BuildIntegrationTests.cs

@@ -381,6 +381,21 @@ public async Task GetBuildVersion_Minus1BuildOffset_NotYetCommitted()
         this.AssertStandardProperties(versionOptions, buildResult);
     }
 
+    [Theory]
+    [InlineData(0)]
+    [InlineData(21)]
+    public async Task GetBuildVersion_BuildNumberSpecifiedInVersionJson(int buildNumber)
+    {
+        var versionOptions = new VersionOptions
+        {
+            Version = SemanticVersion.Parse("14.0." + buildNumber),
+        };
+        this.WriteVersionFile(versionOptions);
+        this.InitializeSourceControl();
+        var buildResult = await this.BuildAsync();
+        this.AssertStandardProperties(versionOptions, buildResult);
+    }
+
     [Fact]
     public async Task PublicRelease_RegEx_Unsatisfied()
     {
@@ -821,6 +836,7 @@ private void AssertStandardProperties(VersionOptions versionOptions, BuildResult
         Assert.Equal($"{version}", buildResult.BuildVersion);
         Assert.Equal($"{idAsVersion.Major}.{idAsVersion.Minor}.{idAsVersion.Build}", buildResult.BuildVersion3Components);
         Assert.Equal(idAsVersion.Build.ToString(), buildResult.BuildVersionNumberComponent);
+        Assert.Equal(versionOptions.Version.Version.Build != -1 ? versionOptions.Version.Version.Build.ToString() : string.Empty, buildResult.BuildNumberFromVersionJson);
         Assert.Equal($"{idAsVersion.Major}.{idAsVersion.Minor}.{idAsVersion.Build}", buildResult.BuildVersionSimple);
         Assert.Equal(this.Repo.Head.Commits.First().Id.Sha, buildResult.GitCommitId);
         Assert.Equal(commitIdShort, buildResult.GitCommitIdShort);
@@ -980,6 +996,7 @@ internal BuildResults(BuildResult buildResult, IReadOnlyList<BuildEventArgs> log
         public string PrereleaseVersion => this.BuildResult.ProjectStateAfterBuild.GetPropertyValue("PrereleaseVersion");
         public string MajorMinorVersion => this.BuildResult.ProjectStateAfterBuild.GetPropertyValue("MajorMinorVersion");
         public string BuildVersionNumberComponent => this.BuildResult.ProjectStateAfterBuild.GetPropertyValue("BuildVersionNumberComponent");
+        public string BuildNumberFromVersionJson => this.BuildResult.ProjectStateAfterBuild.GetPropertyValue("BuildNumberFromVersionJson");
         public string GitCommitIdShort => this.BuildResult.ProjectStateAfterBuild.GetPropertyValue("GitCommitIdShort");
         public string GitVersionHeight => this.BuildResult.ProjectStateAfterBuild.GetPropertyValue("GitVersionHeight");
         public string SemVerBuildSuffix => this.BuildResult.ProjectStateAfterBuild.GetPropertyValue("SemVerBuildSuffix");

src/NerdBank.GitVersioning/VersionOracle.cs

@@ -159,6 +159,12 @@ public IEnumerable<string> BuildMetadataWithCommitId
         /// </summary>
         public int BuildNumber => Math.Max(0, this.Version.Build);
 
+        /// <summary>
+        /// Gets the build number as it was specified in the version.json file.
+        /// </summary>
+        /// <value>The version specified, or -1 if none was specified.</value>
+        public int BuildNumberFromVersionOptions => this.VersionOptions?.Version?.Version?.Build ?? -1;
+
         /// <summary>
         /// Gets or sets the major.minor version string.
         /// </summary>

src/Nerdbank.GitVersioning.NuGet/build/Nerdbank.GitVersioning.targets

@@ -69,6 +69,7 @@
       <Output TaskParameter="GitVersionHeight" PropertyName="GitVersionHeight" />
       <Output TaskParameter="BuildNumber" PropertyName="BuildNumber" />
       <Output TaskParameter="BuildNumber" PropertyName="BuildVersionNumberComponent" />
+      <Output TaskParameter="BuildNumberFromVersionJson" PropertyName="BuildNumberFromVersionJson" />
       <Output TaskParameter="PublicRelease" PropertyName="PublicRelease" />
       <Output TaskParameter="CloudBuildNumber" PropertyName="CloudBuildNumber" Condition=" '$(CloudBuildNumber)' == '' "/>
       <Output TaskParameter="BuildMetadataFragment" PropertyName="SemVerBuildSuffix" />

src/Nerdbank.GitVersioning.Tasks/GetBuildVersion.cs

@@ -2,6 +2,7 @@
 {
     using System;
     using System.Collections.Generic;
+    using System.Globalization;
     using System.IO;
     using System.Linq;
     using Microsoft.Build.Framework;
@@ -139,6 +140,12 @@ public GetBuildVersion()
         [Output]
         public int BuildNumber { get; private set; }
 
+        /// <summary>
+        /// Gets the build number as specified in the version.json file.
+        /// </summary>
+        [Output]
+        public string BuildNumberFromVersionJson { get; private set; }
+
         /// <summary>
         /// Gets the BuildNumber to set the cloud build to (if applicable).
         /// </summary>
@@ -174,6 +181,7 @@ protected override bool ExecuteInner()
                 this.SimpleVersion = oracle.SimpleVersion.ToString();
                 this.MajorMinorVersion = oracle.MajorMinorVersion.ToString();
                 this.BuildNumber = oracle.BuildNumber;
+                this.BuildNumberFromVersionJson = oracle.BuildNumberFromVersionOptions != -1 ? oracle.BuildNumberFromVersionOptions.ToString(CultureInfo.InvariantCulture) : string.Empty;
                 this.PrereleaseVersion = oracle.PrereleaseVersion;
                 this.GitCommitId = oracle.GitCommitId;
                 this.GitCommitIdShort = oracle.GitCommitIdShort;