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Add support for registering custom merge drivers
libgit2#2107
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12 files changed

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‎LibGit2Sharp.Tests/MergeDriverFixture.cs‎

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using System;
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using System.IO;
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using System.Linq;
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using LibGit2Sharp.Tests.TestHelpers;
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using Xunit;
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namespace LibGit2Sharp.Tests
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{
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public class MergeDriverFixture : BaseFixture
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{
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private const string MergeDriverName = "the-merge-driver";
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[Fact]
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public void CanRegisterAndUnregisterTheSameMergeDriver()
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{
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var mergeDriver = new EmptyMergeDriver(MergeDriverName);
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var registration = GlobalSettings.RegisterMergeDriver(mergeDriver);
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GlobalSettings.DeregisterMergeDriver(registration);
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var secondRegistration = GlobalSettings.RegisterMergeDriver(mergeDriver);
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GlobalSettings.DeregisterMergeDriver(secondRegistration);
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}
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[Fact]
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public void CanRegisterAndDeregisterAfterGarbageCollection()
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{
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var registration = GlobalSettings.RegisterMergeDriver(new EmptyMergeDriver(MergeDriverName));
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GC.Collect();
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GlobalSettings.DeregisterMergeDriver(registration);
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}
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[Fact]
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public void SameMergeDriverIsEqual()
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{
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var mergeDriver = new EmptyMergeDriver(MergeDriverName);
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Assert.Equal(mergeDriver, mergeDriver);
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}
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[Fact]
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public void InitCallbackNotMadeWhenMergeDriverNeverUsed()
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{
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bool called = false;
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void initializeCallback()
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{
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called = true;
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}
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var driver = new FakeMergeDriver(MergeDriverName, initializeCallback);
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var registration = GlobalSettings.RegisterMergeDriver(driver);
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try
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{
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Assert.False(called);
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}
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finally
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{
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GlobalSettings.DeregisterMergeDriver(registration);
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}
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}
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[Fact]
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public void WhenMergingApplyIsCalledWhenThereIsAConflict()
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{
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string repoPath = InitNewRepository();
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bool called = false;
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MergeDriverResult apply(MergeDriverSource source)
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{
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called = true;
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return new MergeDriverResult { Status = MergeStatus.Conflicts };
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}
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var mergeDriver = new FakeMergeDriver(MergeDriverName, applyCallback: apply);
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var registration = GlobalSettings.RegisterMergeDriver(mergeDriver);
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try
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{
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using (var repo = CreateTestRepository(repoPath))
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{
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string newFilePath = Touch(repo.Info.WorkingDirectory, Guid.NewGuid() + ".txt", "file1");
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var stageNewFile = new FileInfo(newFilePath);
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Commands.Stage(repo, newFilePath);
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repo.Commit("Commit", Constants.Signature, Constants.Signature);
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var branch = repo.CreateBranch("second");
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var id = Guid.NewGuid() + ".txt";
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newFilePath = Touch(repo.Info.WorkingDirectory, id, "file2");
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stageNewFile = new FileInfo(newFilePath);
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Commands.Stage(repo, newFilePath);
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repo.Commit("Commit in master", Constants.Signature, Constants.Signature);
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Commands.Checkout(repo, branch.FriendlyName);
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newFilePath = Touch(repo.Info.WorkingDirectory, id, "file3");
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stageNewFile = new FileInfo(newFilePath);
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Commands.Stage(repo, newFilePath);
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repo.Commit("Commit in second branch", Constants.Signature, Constants.Signature);
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var result = repo.Merge("master", Constants.Signature, new MergeOptions { CommitOnSuccess = false });
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Assert.True(called);
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}
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}
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finally
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{
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GlobalSettings.DeregisterMergeDriver(registration);
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}
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}
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[Fact]
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public void MergeDriverCanFetchFileContents()
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{
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string repoPath = InitNewRepository();
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MergeDriverResult apply(MergeDriverSource source)
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{
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var repos = source.Repository;
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var blob = repos.Lookup<Blob>(source.Theirs.Id);
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var content = blob.GetContentStream();
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return new MergeDriverResult { Status = MergeStatus.UpToDate, Content = content };
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}
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var mergeDriver = new FakeMergeDriver(MergeDriverName, applyCallback: apply);
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var registration = GlobalSettings.RegisterMergeDriver(mergeDriver);
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try
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{
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using (var repo = CreateTestRepository(repoPath))
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{
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string newFilePath = Touch(repo.Info.WorkingDirectory, Guid.NewGuid() + ".txt", "file1");
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var stageNewFile = new FileInfo(newFilePath);
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Commands.Stage(repo, newFilePath);
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repo.Commit("Commit", Constants.Signature, Constants.Signature);
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var branch = repo.CreateBranch("second");
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var id = Guid.NewGuid() + ".txt";
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newFilePath = Touch(repo.Info.WorkingDirectory, id, "file2");
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stageNewFile = new FileInfo(newFilePath);
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Commands.Stage(repo, newFilePath);
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repo.Commit("Commit in master", Constants.Signature, Constants.Signature);
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Commands.Checkout(repo, branch.FriendlyName);
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newFilePath = Touch(repo.Info.WorkingDirectory, id, "file3");
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stageNewFile = new FileInfo(newFilePath);
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Commands.Stage(repo, newFilePath);
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repo.Commit("Commit in second branch", Constants.Signature, Constants.Signature);
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var result = repo.Merge("master", Constants.Signature, new MergeOptions { CommitOnSuccess = false });
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}
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}
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finally
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{
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GlobalSettings.DeregisterMergeDriver(registration);
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}
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}
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[Fact]
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public void DoubleRegistrationFailsButDoubleDeregistrationDoesNot()
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{
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Assert.Empty(GlobalSettings.GetRegisteredMergeDrivers());
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var mergeDriver = new EmptyMergeDriver(MergeDriverName);
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var registration = GlobalSettings.RegisterMergeDriver(mergeDriver);
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Assert.Throws<EntryExistsException>(() => { GlobalSettings.RegisterMergeDriver(mergeDriver); });
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Assert.Single(GlobalSettings.GetRegisteredMergeDrivers());
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Assert.True(registration.IsValid, "MergeDriverRegistration.IsValid should be true.");
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GlobalSettings.DeregisterMergeDriver(registration);
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Assert.Empty(GlobalSettings.GetRegisteredMergeDrivers());
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Assert.False(registration.IsValid, "MergeDriverRegistration.IsValid should be false.");
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GlobalSettings.DeregisterMergeDriver(registration);
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Assert.Empty(GlobalSettings.GetRegisteredMergeDrivers());
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Assert.False(registration.IsValid, "MergeDriverRegistration.IsValid should be false.");
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}
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private static FileInfo CommitFileOnBranch(Repository repo, string branchName, String content)
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{
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var branch = repo.CreateBranch(branchName);
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Commands.Checkout(repo, branch.FriendlyName);
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FileInfo expectedPath = StageNewFile(repo, content);
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repo.Commit("Commit", Constants.Signature, Constants.Signature);
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return expectedPath;
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}
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private static FileInfo StageNewFile(IRepository repo, string contents = "null")
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{
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string newFilePath = Touch(repo.Info.WorkingDirectory, Guid.NewGuid() + ".txt", contents);
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var stageNewFile = new FileInfo(newFilePath);
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Commands.Stage(repo, newFilePath);
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return stageNewFile;
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}
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private Repository CreateTestRepository(string path)
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{
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var repository = new Repository(path);
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CreateConfigurationWithDummyUser(repository, Constants.Identity);
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CreateAttributesFile(repository, "* merge=the-merge-driver");
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return repository;
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}
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class EmptyMergeDriver : MergeDriver
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{
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public EmptyMergeDriver(string name)
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: base(name)
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{ }
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protected override MergeDriverResult Apply(MergeDriverSource source)
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{
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throw new NotImplementedException();
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}
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protected override void Initialize()
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{
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throw new NotImplementedException();
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}
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}
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class FakeMergeDriver : MergeDriver
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{
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private readonly Action initCallback;
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private readonly Func<MergeDriverSource, MergeDriverResult> applyCallback;
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public FakeMergeDriver(string name, Action initCallback = null, Func<MergeDriverSource, MergeDriverResult> applyCallback = null)
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: base(name)
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{
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this.initCallback = initCallback;
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this.applyCallback = applyCallback;
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}
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protected override void Initialize()
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{
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initCallback?.Invoke();
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}
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protected override MergeDriverResult Apply(MergeDriverSource source)
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{
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if (applyCallback != null)
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return applyCallback(source);
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return new MergeDriverResult { Status = MergeStatus.UpToDate };
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}
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}
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}
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}

‎LibGit2Sharp/Core/GitBuf.cs‎

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@@ -15,4 +15,12 @@ public void Dispose()
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Proxy.git_buf_dispose(this);
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}
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}
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[StructLayout(LayoutKind.Sequential)]
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unsafe struct git_buf
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{
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public IntPtr ptr;
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public UIntPtr asize;
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public UIntPtr size;
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}
1826
}

‎LibGit2Sharp/Core/GitErrorCategory.cs‎

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Original file line numberDiff line numberDiff line change
@@ -36,6 +36,7 @@ internal enum GitErrorCategory
3636
Filesystem,
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Patch,
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Worktree,
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Sha1
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Sha1,
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MergeDriver
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}
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}

‎LibGit2Sharp/Core/GitMergeDriver.cs‎

Lines changed: 57 additions & 0 deletions
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@@ -0,0 +1,57 @@
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using System;
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using System.Runtime.InteropServices;
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namespace LibGit2Sharp.Core
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{
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[StructLayout(LayoutKind.Sequential)]
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internal struct GitMergeDriver
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{
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/** The `version` should be set to `GIT_MERGE_DRIVER_VERSION`. */
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public uint version;
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/** Called when the merge driver is first used for any file. */
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[MarshalAs(UnmanagedType.FunctionPtr)]
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public git_merge_driver_init_fn initialize;
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/** Called when the merge driver is unregistered from the system. */
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[MarshalAs(UnmanagedType.FunctionPtr)]
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public git_merge_driver_shutdown_fn shutdown;
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/**
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* Called to merge the contents of a conflict. If this function
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* returns `GIT_PASSTHROUGH` then the default (`text`) merge driver
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* will instead be invoked. If this function returns
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* `GIT_EMERGECONFLICT` then the file will remain conflicted.
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*/
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[MarshalAs(UnmanagedType.FunctionPtr)]
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public git_merge_driver_apply_fn apply;
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internal delegate int git_merge_driver_init_fn(IntPtr merge_driver);
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internal delegate void git_merge_driver_shutdown_fn(IntPtr merge_driver);
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/** Called when the merge driver is invoked due to a file level merge conflict. */
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internal delegate int git_merge_driver_apply_fn(
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IntPtr merge_driver,
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IntPtr path_out,
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UIntPtr mode_out,
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IntPtr merged_out,
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IntPtr driver_name,
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IntPtr merge_driver_source
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);
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}
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/// <summary>
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/// The file source being merged
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/// </summary>
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[StructLayout(LayoutKind.Sequential)]
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internal unsafe struct git_merge_driver_source
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{
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public git_repository* repository;
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readonly char *default_driver;
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readonly IntPtr file_opts;
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public git_index_entry* ancestor;
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public git_index_entry* ours;
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public git_index_entry* theirs;
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}
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}

‎LibGit2Sharp/Core/NativeMethods.cs‎

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@@ -360,6 +360,9 @@ internal static extern unsafe int git_branch_upstream_name(
360360
[DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
361361
internal static extern void git_buf_dispose(GitBuf buf);
362362

363+
[DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
364+
internal static extern int git_buf_grow(IntPtr buf, uint target_size);
365+
363366
[DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
364367
internal static extern unsafe int git_checkout_tree(
365368
git_repository* repo,
@@ -989,6 +992,16 @@ internal static extern unsafe int git_merge(
989992
ref GitMergeOpts merge_opts,
990993
ref GitCheckoutOpts checkout_opts);
991994

995+
[DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
996+
internal static extern int git_merge_driver_register(
997+
[MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name,
998+
IntPtr gitMergeDriver);
999+
1000+
[DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
1001+
internal static extern int git_merge_driver_unregister(
1002+
[MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))]string name);
1003+
1004+
9921005
[DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
9931006
internal static extern unsafe int git_merge_commits(
9941007
out git_index* index,

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