Add tests to ensure that source and target must not be the same repository · Entire

Add tests to ensure that source and target must not be the same repository

Summary of changes:

• internal/validation/validation.go — added ValidateEndpoints(sourceURL, targetURL) that rejects identical (whitespace-trimmed) URLs and ignores empties so the existing "missing URL" errors stay specific.
• internal/syncer/syncer.go — newSession now calls ValidateEndpoints when a target is required, before any network I/O.
• internal/validation/validation_test.go — TestValidateEndpoints covers same/different/whitespace/empty/trailing-slash cases.
• internal/syncer/syncer_test.go — TestPublicAPIRejectsIdenticalSourceAndTarget proves Run, Bootstrap, and Probe-with-target all reject same URLs; TestProbeWithoutTargetIgnoresEndpointEqualityCheck guards against false positives when probe has no target.

For --prune add negative tests

Committed as 834619c on changes:

• Proving --branch main --prune and --map main:stable --prune preserve unrelated target branches.

GPG signing issue:

Register an empty config plugin empty.go via Register(ConfigLoader(), func() ConfigSource { return config.NewEmpty() }) to remove settings such as gpgsign from both global and system levels.

What I added:

• internal/planner/planner_test.go: TestBuildPlansPrunePreservesUnrelatedBranchesUnderFilter and TestBuildReplicationPlansPrunePreservesUnrelatedBranchesUnderFilter. Both are table-driven over the two scenarios (--branch main and --map main:stable) and prove the prune-scoping rule directly at the planner layer.
• internal/syncer/integration_test.go: TestRun_IntegrationPrunePreservesUnrelatedTargetBranchUnderFilter — end-to-end via the real Run pipeline against smart-HTTP servers. First sync seeds the target, then a release orphan is added, then the filtered --prune run must leave it intact.

On the gpgSign disable:

Committed as d4cca23:

• Moved init() from internal/syncertest/plugin.go to a dedicated production package, cleaner placement.

Integration Tests:

• Added TestRun_IntegrationSyncPruneDeletesOrphanedBranch to confirm orphan deletion and preservation of branch during sync with Prune: true.

New Test Assertions:

• When --tags is unset, sync's --prune only operates on branches, preserving tags created after the prior sync.
• Added TestRun_IntegrationSyncPruneTagsPreservesTagCreatedDuringSync to check tag preservation during sync.

Commit Summary:

• Managed incremental push failures and recovery in TestRun_IntegrationIncrementalPushFailureRecoversOnRetry.