Exceptions during hg push should be errors

.gitignore

@@ -1,6 +1,7 @@
 .idea/
 .vs/
 *.files
+*.lscache
 *.mdb
 *.nupkg
 *.orig

src/LibChorus/VcsDrivers/Mercurial/HgRepository.cs

@@ -294,16 +294,9 @@ public bool Pull(RepositoryAddress source, string targetUri)
 
 		public void PushToTarget(string targetLabel, string targetUri)
 		{
-			try
-			{
-				CheckAndUpdateHgrc();
-				Execute(false, _mercurialTwoCompatible,SecondsBeforeTimeoutOnRemoteOperation, "push --new-branch " + GetProxyConfigParameterString(targetUri), SurroundWithQuotes(targetUri));
-			}
-			catch (Exception err)
-			{
-				_progress.WriteMessageWithColor("OrangeRed",
-					$"Could not send to {ServerSettingsModel.RemovePasswordForLog(targetUri)}{Environment.NewLine}{err.Message}");
-			}
+			CheckAndUpdateHgrc();
+			Execute(false, _mercurialTwoCompatible, SecondsBeforeTimeoutOnRemoteOperation,
+				"push --new-branch " + GetProxyConfigParameterString(targetUri), SurroundWithQuotes(targetUri));
 
 			if (GetIsLocalUri(targetUri))
 			{
@@ -313,8 +306,9 @@ public void PushToTarget(string targetLabel, string targetUri)
 				}
 				catch (Exception err)
 				{
-					_progress.WriteMessageWithColor("OrangeRed",
-						$"Could not update the actual files after a pushing to {ServerSettingsModel.RemovePasswordForLog(targetUri)}{Environment.NewLine}{err.Message}");
+					throw new ApplicationException(
+						$"Could not update the actual files after pushing to {ServerSettingsModel.RemovePasswordForLog(targetUri)}",
+						err);
 				}
 			}
 		}

src/LibChorus/sync/Synchronizer.cs

@@ -251,16 +251,39 @@ public void SetIsOneOfDefaultSyncAddresses(RepositoryAddress address, bool enabl
 	   private void SendToOthers(HgRepository repo, List<RepositoryAddress> sourcesToTry, Dictionary<RepositoryAddress, bool> connectionAttempt)
 		{
 			using var activity = LibChorusActivitySource.Value.StartActivity();
+			List<Exception> errors = new List<Exception>();
+			bool atLeastOneSucceeded = false;
 			foreach (RepositoryAddress address in sourcesToTry)
 			{
 				ThrowIfCancelPending();
 
 				if (!address.IsReadOnly)
 				{
-					SendToOneOther(address, connectionAttempt, repo);
+					try
+					{
+						SendToOneOther(address, connectionAttempt, repo);
+						atLeastOneSucceeded = true;
+					}
+					catch (UserCancelledException)
+					{
+						throw;
+					}
+					catch (Exception e)
+					{
+						_progress.WriteException(e);
+						_progress.WriteError(e.Message);
+						errors.Add(e);
+					}
 				}
 			}
 			ThrowIfCancelPending();
+
+			// Only throw and fail the sync if every writable target failed; partial success still counts as success.
+			if (errors.Any() && !atLeastOneSucceeded)
+			{
+				var error = errors.Count == 1 ? errors.Single() : new AggregateException(errors);
+				throw new SynchronizationException(error, WhatToDo.CheckAddressAndConnection, "Failed to send changes");
+			}
 		}
 
 		private void ThrowIfCancelPending()

src/LibChorusTests/sync/Synchronizer.BadSituationTests.cs

@@ -4,6 +4,7 @@
 using Chorus.merge;
 using Chorus.sync;
 using Chorus.Utilities;
+using Chorus.VcsDrivers;
 using Chorus.VcsDrivers.Mercurial;
 using LibChorus.TestUtilities;
 using NUnit.Framework;
@@ -55,6 +56,81 @@ public void Sync_HgrcInUseByOther_FailsGracefully()
 			}
 		}
 
+		[Test]
+		public void Sync_PushFails_ErrorEncounteredIsSet()
+		{
+			using (var sender = new RepositorySetup("sender"))
+			{
+				sender.AddAndCheckinFile("one.txt", "sender's content");
+
+				var options = new SyncOptions
+				{
+					DoMergeWithOthers = false,
+					DoPullFromOthers = false,
+					DoSendToOthers = true,
+				};
+				options.RepositorySourcesToTry.Add(new FailingConnectableHttpRepositoryAddress("test-repo"));
+
+				var result = sender.SyncWithOptions(options);
+				Assert.That(result.Succeeded, Is.False);
+				Assert.That(result.ErrorEncountered, Is.Not.Null);
+				Assert.That(result.ErrorEncountered.Message, Does.Contain("Failed to send changes"));
+				Assert.That(sender.GetProgressString(), Does.Contain("Failed to send to test-repo"));
+			}
+		}
+
+		[Test]
+		public void Sync_FirstPushFails_OtherSourcesStillTried()
+		{
+			using (var sender = new RepositorySetup("sender"))
+			{
+				sender.AddAndCheckinFile("one.txt", "sender's content");
+
+				var options = new SyncOptions
+				{
+					DoMergeWithOthers = false,
+					DoPullFromOthers = false,
+					DoSendToOthers = true,
+				};
+				options.RepositorySourcesToTry.Add(new FailingConnectableHttpRepositoryAddress("first-test-repo"));
+				options.RepositorySourcesToTry.Add(new FailingConnectableHttpRepositoryAddress("second-test-repo"));
+
+				var result = sender.SyncWithOptions(options);
+				Assert.That(result.Succeeded, Is.False);
+				Assert.That(result.ErrorEncountered, Is.Not.Null);
+				// Both targets should have been attempted even though the first failed.
+				var progress = sender.GetProgressString();
+				Assert.That(progress, Does.Contain("Failed to send to first-test-repo"));
+				Assert.That(progress, Does.Contain("Failed to send to second-test-repo"));
+			}
+		}
+
+		[Test]
+		public void Sync_OneOfMultiplePushTargetsFails_SyncStillSucceeds()
+		{
+			using (var sender = new RepositorySetup("sender"))
+			{
+				sender.AddAndCheckinFile("one.txt", "sender's content");
+
+				using (var receiver = new RepositorySetup("receiver", sender))
+				{
+					var options = new SyncOptions
+					{
+						DoMergeWithOthers = false,
+						DoPullFromOthers = false,
+						DoSendToOthers = true,
+					};
+					options.RepositorySourcesToTry.Add(new FailingConnectableHttpRepositoryAddress("test-repo"));
+					options.RepositorySourcesToTry.Add(receiver.GetRepositoryAddress());
+
+					var result = sender.SyncWithOptions(options);
+					Assert.That(result.Succeeded, Is.True);
+					Assert.That(result.ErrorEncountered, Is.Null);
+					Assert.That(sender.GetProgressString(), Does.Contain("Failed to send to test-repo"));
+				}
+			}
+		}
+
 		[Test]
 		public void Sync_ExceptionInMergeCode_LeftWith2HeadsAndErrorOutputToProgress()
 		{
@@ -518,5 +594,27 @@ public void Sync_NewFileWithNonAsciCharacters_FileAdded()
 			}
 		}
 
+		/// <summary>
+		/// Test double that bypasses HttpRepositoryPath's remote validation.
+		/// HttpRepositoryPath.CanConnect() validates the endpoint and aborts if invalid, preventing
+		/// sync operations from executing. This allows CanConnect() to return true while sync operations
+		/// fail, enabling tests of sync failure scenarios (push/pull/merge failures).
+		/// </summary>
+		private class FailingConnectableHttpRepositoryAddress : RepositoryAddress
+		{
+			public FailingConnectableHttpRepositoryAddress(string name) : base(name, "http://127.0.0.1:1/test-project", false)
+			{
+			}
+
+			public override bool CanConnect(HgRepository localRepository, string projectName, IProgress progress)
+			{
+				return true;
+			}
+
+			public override string GetPotentialRepoUri(string repoIdentifier, string projectName, IProgress progress)
+			{
+				return URI;
+			}
+		}
 	}
-}
+}