Make all non-user-creatable structures non-comparable (#802)

This change makes all non-user-creatable structures non-comparable. This
makes it easier to add changes later that don't introduce breaking
changes from the go compatibility guarantees perspective.

This, of course, implies that this change _is_ a breaking change, but since
these structures are not intended to be created by users (or de-referenced),
it should be okay.

1 files changed, 2 insertions, 0 deletions

diff --git a/diff.go b/diff.go
index fab4fce..308859a 100644
--- a/diff.go
+++ b/diff.go
@@ -132,6 +132,7 @@ func diffLineFromC(line *C.git_diff_line) DiffLine {
 }
 
 type Diff struct {
+	doNotCompare
 	ptr          *C.git_diff
 	repo         *Repository
 	runFinalizer bool
@@ -219,6 +220,7 @@ func (diff *Diff) FindSimilar(opts *DiffFindOptions) error {
 }
 
 type DiffStats struct {
+	doNotCompare
 	ptr *C.git_diff_stats
 }