krino: duplicates are found, never deleted

A rule combining (duplicate) with a delete action is refused at load, and a
file that is a duplicate under any duplicate scope its directory uses gets no
delete step from any rule: the plan shows it skipped and the chain continues.
A failed duplicate check blocks the delete too. Tests cover (matched), another
rule's own condition, a test evaluation skipped, two scopes and a failed
check, each checking every copy is still on disk.

1 files changed, 8 insertions, 0 deletions

diff --git a/internal/plan/chain.go b/internal/plan/chain.go
index bfa2484..e504504 100644
--- a/internal/plan/chain.go
+++ b/internal/plan/chain.go
@@ -32,6 +32,10 @@ func NewClaims() *Claims {
 type Input struct {
 	File  scan.File
 	Rules []RuleMatch
+	// NoDelete, when non-empty, skips every delete step of this file with
+	// this text as the step's Skip, without ending the chain (spec §5.5
+	// rule 2, §7.1).
+	NoDelete string
 }
 
 // Build turns each file's matching rules into a chain. root is the
@@ -166,6 +170,10 @@ func buildOne(root string, in Input, now time.Time, d Disk, claim claimed) Chain
 				}
 
 			case config.Delete, config.DeletePermanent:
+				if in.NoDelete != "" {
+					step.Skip = in.NoDelete
+					break
+				}
 				deletedBy = rule.Name
 			}