bin/bisect-database-dumps: also bisect for "when did x vanish"

1 files changed, 14 insertions, 1 deletions

diff --git a/bin/bisect-database-dumps b/bin/bisect-database-dumps
index deb88f8..7ccbe16 100755
--- a/bin/bisect-database-dumps
+++ b/bin/bisect-database-dumps
@@ -13,7 +13,19 @@ has=$(
 )
 
 if ! xzgrep -q "$@" "${has}"; then
-  >&2 printf 'cannot find "%s" in the latest dump\n' "$*"
+  >&2 printf 'cannot find "%s" in the latest dump - swapping directions\n' "$*"
+  dumps=$(
+    printf '%s\n' "${dumps}" | \
+      tac
+  )
+  has=$(
+    printf '%s\n' "$dumps" | \
+      tail -n1
+  )
+  if ! xzgrep -q "$@" "${has}"; then
+    >&2 printf 'cannot find "%s" in the earliest dump either - swapping directions did not help\n' "$*"
+    exit 1
+  fi
 fi
 
 has_not=$(
@@ -23,6 +35,7 @@ has_not=$(
 
 if xzgrep -q "$@" "${has_not}"; then
   >&2 printf 'first dump does also have "%s"\n' "$*"
+  exit 1
 fi
 
 count=$(