Workflow: pdf input defaults to empty (dry run falls back to the Clark regression sample)

.gitea/workflows/audiobook.yml

@@ -9,9 +9,9 @@ on:
   workflow_dispatch:
     inputs:
       pdf:
-        description: 'PDF path inside the repo (empty = every PDF waiting in _incoming/)'
+        description: 'PDF path inside the repo (empty = every PDF waiting in _incoming/; a dry run with nothing waiting uses the Clark book as a regression sample)'
         required: false
-        default: 'books/clark-glenn/the-man-who-tapped-the-secrets-of-the-universe/The Man Who Tapped the Secrets of the Universe - by Glenn Clark (Walter Russell).pdf'
+        default: ''
       voice_endpoint:
         description: 'Testing only: use this voice URL instead of the default (for example to prove a failed voice run commits nothing)'
         required: false

_pipeline/ci/run.sh

@@ -24,6 +24,12 @@ if [ -n "${PDF_INPUT:-}" ]; then
 else
   while IFS= read -r f; do pdfs+=("$f"); done < <(find _incoming -maxdepth 1 -type f -iname '*.pdf' | sort)
 fi
+CLARK_PDF="books/clark-glenn/the-man-who-tapped-the-secrets-of-the-universe/The Man Who Tapped the Secrets of the Universe - by Glenn Clark (Walter Russell).pdf"
+if [ "${#pdfs[@]}" -eq 0 ] && [ "$DRY_RUN" = "true" ]; then
+  echo "Dry run with nothing in _incoming/: using the Clark book as a regression sample."
+  sparse_add "/$(esc "$CLARK_PDF")"
+  pdfs=("$CLARK_PDF")
+fi
 if [ "${#pdfs[@]}" -eq 0 ]; then
   echo "Nothing to do: no PDF in _incoming/."
   exit 0