get commit short id from git repo (#304)

Author: ctaggart

doc/versionJson.md

@@ -28,6 +28,8 @@ The content of the version.json file is a JSON serialized object with these prop
   "assemblyVersion": "x.y", // optional. Use when x.y for AssemblyVersionAttribute differs from the default version property.
   "buildNumberOffset": "zOffset", // optional. Use when you need to add/subtract a fixed value from the computed build number.
   "semVer1NumericIdentifierPadding": 4, // optional. Use when your -prerelease includes numeric identifiers and need semver1 support.
+  "gitCommitIdShortFixedLength": 10, // optional. Set the commit ID abbreviation length.
+  "gitCommitIdShortAutoMinimum": 0, // optional. Set to use the short commit ID abbreviation provided by the git repository.
   "nugetPackageVersion": {
      "semVer": 1 // optional. Set to either 1 or 2 to control how the NuGet package version string is generated. Default is 1.
   },

src/NerdBank.GitVersioning.Tests/BuildIntegrationTests.cs

@@ -72,7 +72,7 @@ public BuildIntegrationTests(ITestOutputHelper logger)
         }
     }
 
-    private string CommitIdShort => this.Repo.Head.Commits.First().Id.Sha.Substring(0, 10);
+    private string CommitIdShort => this.Repo.Head.Commits.First().Id.Sha.Substring(0, VersionOptions.DefaultGitCommitIdShortFixedLength);
 
     protected override void Dispose(bool disposing)
     {
@@ -176,7 +176,7 @@ public async Task GetBuildVersion_In_Git_But_Head_Lacks_VersionFile()
         Assumes.True(repo.Index[VersionFile.JsonFileName] == null);
         var buildResult = await this.BuildAsync();
         Assert.Equal("3.4.0." + repo.Head.Commits.First().GetIdAsVersion().Revision, buildResult.BuildVersion);
-        Assert.Equal("3.4.0+" + repo.Head.Commits.First().Id.Sha.Substring(0, 10), buildResult.AssemblyInformationalVersion);
+        Assert.Equal("3.4.0+" + repo.Head.Commits.First().Id.Sha.Substring(0, VersionOptions.DefaultGitCommitIdShortFixedLength), buildResult.AssemblyInformationalVersion);
     }
 
     [Fact]
@@ -201,7 +201,7 @@ public async Task GetBuildVersion_In_Git_No_VersionFile_At_All()
         repo.Commit("empty", this.Signer, this.Signer, new CommitOptions { AllowEmptyCommit = true });
         var buildResult = await this.BuildAsync();
         Assert.Equal("0.0.1." + repo.Head.Commits.First().GetIdAsVersion().Revision, buildResult.BuildVersion);
-        Assert.Equal("0.0.1+" + repo.Head.Commits.First().Id.Sha.Substring(0, 10), buildResult.AssemblyInformationalVersion);
+        Assert.Equal("0.0.1+" + repo.Head.Commits.First().Id.Sha.Substring(0, VersionOptions.DefaultGitCommitIdShortFixedLength), buildResult.AssemblyInformationalVersion);
     }
 
     [Fact]

src/NerdBank.GitVersioning.Tests/VersionOracleTests.cs

@@ -15,7 +15,7 @@ public VersionOracleTests(ITestOutputHelper logger)
     {
     }
 
-    private string CommitIdShort => this.Repo.Head.Commits.First().Id.Sha.Substring(0, 10);
+    private string CommitIdShort => this.Repo.Head.Commits.First().Id.Sha.Substring(0, VersionOptions.DefaultGitCommitIdShortFixedLength);
 
     [Fact]
     public void NotRepo()
@@ -180,6 +180,24 @@ public void SemVerStableNonPublicVersion()
         Assert.Matches(@"^2.3.1-g[a-f0-9]{10}$", oracle.ChocolateyPackageVersion);
     }
 
+    [Fact]
+    public void SemVerStableNonPublicVersionShortened()
+    {
+        var workingCopyVersion = new VersionOptions
+        {
+            Version = SemanticVersion.Parse("2.3"),
+            GitCommitIdShortFixedLength = 7
+        };
+        this.WriteVersionFile(workingCopyVersion);
+        this.InitializeSourceControl();
+        var oracle = VersionOracle.Create(this.RepoPath);
+        oracle.PublicRelease = false;
+        Assert.Matches(@"^2.3.1-[^g]{7}$", oracle.SemVer1);
+        Assert.Matches(@"^2.3.1-[^g]{7}$", oracle.SemVer2);
+        Assert.Matches(@"^2.3.1-g[a-f0-9]{7}$", oracle.NuGetPackageVersion);
+        Assert.Matches(@"^2.3.1-g[a-f0-9]{7}$", oracle.ChocolateyPackageVersion);
+    }
+
     [Fact]
     public void DefaultNuGetPackageVersionIsSemVer1PublicRelease()
     {

src/NerdBank.GitVersioning/VersionOptions.cs

@@ -26,6 +26,11 @@ public class VersionOptions : IEquatable<VersionOptions>
         /// </summary>
         private const int DefaultSemVer1NumericIdentifierPadding = 4;
 
+        /// <summary>
+        /// The default value for the <see cref="GitCommitIdShortFixedLength"/> property.
+        /// </summary>
+        public const int DefaultGitCommitIdShortFixedLength = 10;
+
         /// <summary>
         /// The $schema field that should be serialized when writing
         /// </summary>
@@ -88,6 +93,21 @@ public class VersionOptions : IEquatable<VersionOptions>
         [JsonIgnore]
         public int SemVer1NumericIdentifierPaddingOrDefault => this.SemVer1NumericIdentifierPadding ?? DefaultSemVer1NumericIdentifierPadding;
 
+        /// <summary>
+        /// Gets or sets the abbreviated git commit hash length.
+        /// </summary>
+        [JsonProperty(DefaultValueHandling = DefaultValueHandling.Ignore)]
+        public int? GitCommitIdShortFixedLength { get; set; }
+
+        /// <summary>
+        /// Gets or sets the abbreviated git commit hash length minimum value.
+        /// The git repository provides the value.
+        /// If set to 0 or a git repository is not available, <see cref="GitCommitIdShortFixedLength"/> is used.
+        /// The value is 0 by default.
+        /// </summary>
+        [JsonProperty(DefaultValueHandling = DefaultValueHandling.Ignore)]
+        public int? GitCommitIdShortAutoMinimum { get; set; }
+
         /// <summary>
         /// Gets or sets the options around NuGet version strings
         /// </summary>

src/NerdBank.GitVersioning/VersionOracle.cs

@@ -96,6 +96,22 @@ public VersionOracle(string projectDirectory, LibGit2Sharp.Repository repo, LibG
                 this.Version = this.VersionOptions?.Version.Version ?? Version0;
             }
 
+            // get the commit id abbreviation only if the commit id is set
+            if (!string.IsNullOrEmpty(this.GitCommitId))
+            {
+                var gitCommitIdShortFixedLength = this.VersionOptions?.GitCommitIdShortFixedLength ?? VersionOptions.DefaultGitCommitIdShortFixedLength;
+                var gitCommitIdShortAutoMinimum = this.VersionOptions?.GitCommitIdShortAutoMinimum ?? 0;
+                // get it from the git repository if there is a repository present and it is enabled
+                if (repo != null && gitCommitIdShortAutoMinimum > 0)
+                {
+                    this.GitCommitIdShort = repo.ObjectDatabase.ShortenObjectId(commit, gitCommitIdShortAutoMinimum);
+                }
+                else
+                {
+                    this.GitCommitIdShort = this.GitCommitId.Substring(0, gitCommitIdShortFixedLength);
+                }
+            }
+
             this.VersionHeightOffset = this.VersionOptions?.BuildNumberOffsetOrDefault ?? 0;
 
             this.PrereleaseVersion = this.ReplaceMacros(this.VersionOptions?.Version?.Prerelease ?? string.Empty);
@@ -143,7 +159,7 @@ public IEnumerable<string> BuildMetadataWithCommitId
             {
                 if (!string.IsNullOrEmpty(this.GitCommitId))
                 {
-                    yield return this.GitCommitId.Substring(0, 10);
+                    yield return this.GitCommitIdShort;
                 }
 
                 foreach (string identifier in this.BuildMetadata)
@@ -238,7 +254,7 @@ public IEnumerable<string> BuildMetadataWithCommitId
         /// <summary>
         /// Gets the first several characters of the Git revision control commit id for HEAD (the current source code version).
         /// </summary>
-        public string GitCommitIdShort => string.IsNullOrEmpty(this.GitCommitId) ? null : this.GitCommitId.Substring(0, 10);
+        public string GitCommitIdShort { get; }
 
         /// <summary>
         /// Gets the number of commits in the longest single path between

src/NerdBank.GitVersioning/version.schema.json

@@ -68,6 +68,18 @@
           "minimum": 1,
           "maximum": 6
         },
+        "gitCommitIdShortFixedLength": {
+          "type": "integer",
+          "description": "The fixed number of characters to use for the commit ID abbreviation length. This property is ignored if the gitCommitIdShortAutoMinimum property is greater than 0.",
+          "default": 10,
+          "maximum": 40
+        },
+        "gitCommitIdShortAutoMinimum": {
+          "type": "integer",
+          "description": "When greater than 0, the length of the commit ID will be either this value or the shortest unambiguous git-abbreviated commit ID possible, whichever is greater. When 0, the gitCommitIdShortFixedLength property is used instead.",
+          "default": 0,
+          "maximum": 40
+        },
         "nugetPackageVersion": {
           "type": "object",
           "description": "Details for how and what the generated version for NuGet packages will be.",