gui: name the other copy of a duplicate, and offer to keep this one instead

1 files changed, 12 insertions, 0 deletions

diff --git a/internal/engine/facts.go b/internal/engine/facts.go
index 641f1ef..ce05df4 100644
--- a/internal/engine/facts.go
+++ b/internal/engine/facts.go
@@ -158,6 +158,10 @@ type facts struct {
 	// could not read), so (matched) is unknown while none has matched.
 	undecided bool
 
+	// dupOriginal is the file a (duplicate) test last matched against,
+	// absolute, for a front end that offers to act on the other copy.
+	dupOriginal string
+
 	contentDone bool            // extraction was attempted
 	contentErr  error           // why it failed
 	partialErr  error           // extract.ErrPartial: a keyword not found may be in the unread part
@@ -290,9 +294,17 @@ func (f *facts) Duplicate(dirs []string) (string, bool, error) {
 	if !isDup {
 		return "", false, nil
 	}
+	// The absolute path is kept for a front end that has to act on the
+	// other copy - the window offers to keep this one instead - while the
+	// reason text stays as it reads best (plan 21).
+	f.dupOriginal = orig
 	return displayOriginal(orig, root), true, nil
 }
 
+// DuplicateOriginal is the file the last (duplicate) test matched against,
+// absolute; "" when none did.
+func (f *facts) DuplicateOriginal() string { return f.dupOriginal }
+
 // displayOriginal reports orig relative to root when it lies inside root,
 // else home-abbreviated (xdg.Abbrev), as every other user-visible path is.
 func displayOriginal(orig, root string) string {