object/typ: Don't mirror packfiles

Future, ref delta, and offset delta are all implementation details to
the packfile format and may or may not apply elsewhere. object/typ
should only include base object types and should be backend-agnostic
(and TypeInvalid).

Also, object type to property mappings such as isBase should generally
belong in the layer that actually needs them; in this case,
.pack/.idx/.rev.

3 files changed, 6 insertions, 35 deletions

diff --git a/object/typ/type.go b/object/typ/type.go
index 69a07de3..5f7decc1 100644
--- a/object/typ/type.go
+++ b/object/typ/type.go
@@ -1,10 +1,6 @@
 package typ
 
 // Type represents a Git object type.
-//
-// The values currently mirror what's found in the Git packfile format.
-//
-// TODO: Revisit this.
 type Type uint8
 
 const (
@@ -22,17 +18,4 @@ const (
 
 	// TypeTag represents a Git tag.
 	TypeTag Type = 4
-
-	// TypeFuture is reserved for the future, just like in the packfile format.
-	TypeFuture Type = 5
-
-	// TypeOfsDelta is reserved for internal use in packfile handlers.
-	//
-	// TODO: Revisit this.
-	TypeOfsDelta Type = 6
-
-	// TypeRefDelta is reserved for internal use in packfile handlers.
-	//
-	// TODO: Revisit this.
-	TypeRefDelta Type = 7
 )
diff --git a/object/typ/type_details.go b/object/typ/type_details.go
index 48dcf829..ebe1bbbe 100644
--- a/object/typ/type_details.go
+++ b/object/typ/type_details.go
@@ -1,8 +1,7 @@
 package typ
 
 type typeDetails struct {
-	name         string
-	isBaseObject bool
+	name string
 }
 
 func (ty Type) details() typeDetails {
@@ -11,14 +10,11 @@ func (ty Type) details() typeDetails {
 
 //nolint:gochecknoglobals
 var typeTable = [...]typeDetails{
-	TypeInvalid:  {name: "", isBaseObject: false},
-	TypeCommit:   {name: "commit", isBaseObject: true},
-	TypeTree:     {name: "tree", isBaseObject: true},
-	TypeBlob:     {name: "blob", isBaseObject: true},
-	TypeTag:      {name: "tag", isBaseObject: true},
-	TypeFuture:   {name: "", isBaseObject: false},
-	TypeOfsDelta: {name: "", isBaseObject: false},
-	TypeRefDelta: {name: "", isBaseObject: false},
+	TypeInvalid: {name: ""},
+	TypeCommit:  {name: "commit"},
+	TypeTree:    {name: "tree"},
+	TypeBlob:    {name: "blob"},
+	TypeTag:     {name: "tag"},
 }
 
 //nolint:gochecknoglobals
diff --git a/object/typ/type_ops.go b/object/typ/type_ops.go
index 82e68147..535c7296 100644
--- a/object/typ/type_ops.go
+++ b/object/typ/type_ops.go
@@ -1,13 +1,5 @@
 package typ
 
-// IsBaseObject reports whether ty is
-// one of the four ordinary Git object types.
-//
-// TODO: This should probably be removed.
-func (ty Type) IsBaseObject() bool {
-	return ty.details().isBaseObject
-}
-
 // Name returns the canonical Git object type name.
 func (ty Type) Name() (string, bool) {
 	details := ty.details()