From 818eb8cded579c0210459059cead9516b46bfbc4 Mon Sep 17 00:00:00 2001
From: goanscryca <goanscryca@users.noreply.github.com>
Date: Fri, 18 Sep 2026 06:36:15 +0300
Subject: [PATCH] fix(collector): safely handle malformed previous overview and
 allow self-healing

When reading previous state from -output, an invalid or truncated JSON
document (e.g. from an interrupted write or trailing bytes) caused jq
to fail or emit multiple values, breaking --argjson previous and
aborting subsequent collector runs indefinitely.

Now gitwork validates that the previous file is a single JSON object.
If it is invalid or empty, gitwork logs a warning to stderr, falls back
to null (empty state) and replaces the corrupt file with a valid overview
on the current run.

Resolves #1
---
 bin/gitwork             | 6 +++++-
 tests/collector-test.sh | 7 +++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/bin/gitwork b/bin/gitwork
index a957e12..e39c849 100755
--- a/bin/gitwork
+++ b/bin/gitwork
@@ -786,7 +786,11 @@ fi
 
 previous='null'
 if [[ -n $output && -r $output ]]; then
-  previous=$(jq -c . "$output" 2>/dev/null || echo 'null')
+  if prev_val=$(jq -c -s 'if length == 1 and (.[0] | type == "object") then .[0] else empty end' "$output" 2>/dev/null) && [[ -n $prev_val ]]; then
+    previous="$prev_val"
+  elif [[ -s $output ]]; then
+    echo "gitwork: warning: previous overview at $output is invalid JSON; ignoring" >&2
+  fi
 fi
 
 document=$(jqm -n \
diff --git a/tests/collector-test.sh b/tests/collector-test.sh
index ed59368..0d15f68 100755
--- a/tests/collector-test.sh
+++ b/tests/collector-test.sh
@@ -136,6 +136,13 @@ run_dead -output "$out" >/dev/null
 assert_eq "0" "$(jq -e . "$out" >/dev/null 2>&1; echo $?)" "a repeat run leaves valid JSON"
 assert_eq "3" "$(jq -r .schemaVersion "$out")" "a repeat run keeps the schema version"
 
+# A corrupt previous document does not abort the run and self-heals
+printf '{"schemaVersion": 3, "updatedAt": "2026-01-01T00:00:00Z", "providers": []}}\n' >"$out"
+run_dead -output "$out" >/dev/null
+assert_eq "0" "$(jq -e . "$out" >/dev/null 2>&1; echo $?)" "a corrupt previous file is replaced with valid JSON"
+assert_eq "3" "$(jq -r .schemaVersion "$out")" "self-healed run keeps the schema version"
+assert_contains "$(cat "$work/stderr")" "gitwork: warning" "a corrupt previous file emits a warning"
+
 # --- formatting ------------------------------------------------------------
 
 assert_eq "1" "$(run_dead -pretty false | wc -l)" "compact output is one line"