Close export progress in export goroutine

Fixes crash in case of importer exiting prematurely

CHANGES.md

@@ -9,6 +9,7 @@
   history JSON files
 - Allow date time string for `--timestamp` parameter
 - Fixed completed progress bar showing empty
+- Fixed crash in case of importer returning an error on import start
 
 
 ## 0.3.1 - 2023-12-10

internal/backends/export.go

@@ -36,6 +36,7 @@ func (p ListensExportProcessor) ExportBackend() models.Backend {
 
 func (p ListensExportProcessor) Process(oldestTimestamp time.Time, results chan models.ListensResult, progress chan models.Progress) {
 	p.Backend.ExportListens(oldestTimestamp, results, progress)
+	close(progress)
 }
 
 type LovesExportProcessor struct {
@@ -48,4 +49,5 @@ func (p LovesExportProcessor) ExportBackend() models.Backend {
 
 func (p LovesExportProcessor) Process(oldestTimestamp time.Time, results chan models.LovesResult, progress chan models.Progress) {
 	p.Backend.ExportLoves(oldestTimestamp, results, progress)
+	close(progress)
 }

internal/cli/transfer.go

@@ -126,7 +126,6 @@ func (c *TransferCmd[E, I, R]) Transfer(exp backends.ExportProcessor[R], imp bac
 	if result.LastTimestamp.Unix() < timestamp.Unix() {
 		result.LastTimestamp = timestamp
 	}
-	close(exportProgress)
 	wg.Wait()
 	progress.Wait()
 	if result.Error != nil {