1 files changed, 77 insertions, 0 deletions
diff --git a/packfile/ingest/errors.go b/packfile/ingest/errors.go
new file mode 100644
index 00000000..6292d790
--- /dev/null
+++ b/packfile/ingest/errors.go
@@ -0,0 +1,77 @@
+package ingest
+
+import (
+	"errors"
+	"fmt"
+)
+
+// InvalidPackHeaderError reports an invalid or unsupported pack header.
+type InvalidPackHeaderError struct {
+	Reason string
+}
+
+// Error implements error.
+func (err *InvalidPackHeaderError) Error() string {
+	return "packfile/ingest: invalid pack header: " + err.Reason
+}
+
+// PackTrailerMismatchError reports a mismatch between computed and trailer pack hash.
+type PackTrailerMismatchError struct{}
+
+// Error implements error.
+func (err *PackTrailerMismatchError) Error() string {
+	return "packfile/ingest: pack trailer hash mismatch"
+}
+
+// ThinPackUnresolvedError reports unresolved REF deltas when fixThin is disabled
+// or when required bases cannot be found in base.
+type ThinPackUnresolvedError struct {
+	Count int
+}
+
+// Error implements error.
+func (err *ThinPackUnresolvedError) Error() string {
+	return fmt.Sprintf("packfile/ingest: unresolved thin deltas: %d", err.Count)
+}
+
+// MalformedPackEntryError reports malformed entry encoding at one pack offset.
+type MalformedPackEntryError struct {
+	Offset uint64
+	Reason string
+}
+
+// Error implements error.
+func (err *MalformedPackEntryError) Error() string {
+	return fmt.Sprintf("packfile/ingest: malformed pack entry at offset %d: %s", err.Offset, err.Reason)
+}
+
+// DeltaCycleError reports a detected cycle in delta dependency resolution.
+type DeltaCycleError struct {
+	Offset uint64
+}
+
+// Error implements error.
+func (err *DeltaCycleError) Error() string {
+	return fmt.Sprintf("packfile/ingest: delta cycle detected at offset %d", err.Offset)
+}
+
+// DestinationWriteError reports destination I/O failures.
+type DestinationWriteError struct {
+	Op string
+}
+
+// Error implements error.
+func (err *DestinationWriteError) Error() string {
+	return "packfile/ingest: destination write failure: " + err.Op
+}
+
+var errExternalThinBase = errors.New("packfile/ingest: external thin base required")
+
+var (
+	// ErrAlreadyFinalized indicates Continue/Discard already called.
+	ErrAlreadyFinalized = errors.New("packfile/ingest: operation already finalized")
+	// ErrZeroObjectContinue indicates Continue was called for a zero-object pack.
+	ErrZeroObjectContinue = errors.New("packfile/ingest: cannot continue zero-object pack")
+	// ErrNonZeroDiscard indicates Discard was called for a non-zero-object pack.
+	ErrNonZeroDiscard = errors.New("packfile/ingest: cannot discard non-zero pack")
+)