fix(hooks): a locate miss is an answer, not a locate failure

hooks/ix-lib.sh

@@ -270,7 +270,7 @@ parse_json() {
 # Requires: ix_capture_async (from ix-errors.sh, no-op if absent)
 ix_run_text_locate() {
   local _pattern="$1" _path_arg="${2:-}" _lang_arg="${3:-}"
-  local _text_tmp _loc_tmp _text_err _loc_err _TEXT_PID _LOC_PID _is_plain
+  local _text_tmp _loc_tmp _text_err _loc_err _TEXT_PID _LOC_PID _is_plain _loc_status
   local _TEXT_ARGS=("$_pattern" "--limit" "15" "--format" "json")
   [ -n "$_path_arg" ] && _TEXT_ARGS+=("--path" "$_path_arg")
   [ -n "$_lang_arg" ] && _TEXT_ARGS+=("--language" "$_lang_arg")
@@ -308,8 +308,25 @@ ix_run_text_locate() {
   wait "$_TEXT_PID" || ix_capture_async "ix" "ix-text" "text search failed" "$?" \
     "ix text '${_pattern}'" "$(head -3 "$_text_err")"
   [ -n "$_LOC_PID" ] && {
-    wait "$_LOC_PID" || ix_capture_async "ix" "ix-locate" "locate failed" "$?" \
-      "ix locate '${_pattern}'" "$(head -3 "$_loc_err")"
+    # `_loc_status=0; wait || _loc_status=$?` rather than a bare `wait`: these
+    # hooks run under `set -euo pipefail`, so an unguarded non-zero `wait` kills
+    # the hook outright. The `||` also keeps $? intact, which `if ! wait` would
+    # have replaced with the negation's own result.
+    _loc_status=0
+    wait "$_LOC_PID" || _loc_status=$?
+    if [ "$_loc_status" -ne 0 ]; then
+      # An unresolved target exits non-zero but still prints its JSON body
+      # (Ix#539). That is an answer, not a failure -- filing it would record an
+      # error for every symbol a user asks about that does not happen to exist,
+      # and bury real locate failures in the ledger. Only an empty body is a
+      # genuine failure.
+      if [ -s "$_loc_tmp" ]; then
+        ix_log "MISS ix locate exited ${_loc_status} with a body; treated as no-match"
+      else
+        ix_capture_async "ix" "ix-locate" "locate failed" "$_loc_status" \
+          "ix locate '${_pattern}'" "$(head -3 "$_loc_err")"
+      fi
+    fi
   }
 
   _TEXT_RAW=$(cat "$_text_tmp")

tests/mock-ix.sh

@@ -15,6 +15,9 @@
 #   IX_MOCK_EXPECT_INVENTORY_KIND — expected `--kind` arg for `ix inventory`
 #   IX_MOCK_BRIEFING_FILE  — path to fixture for `ix briefing` (default: briefing.json)
 #   IX_MOCK_FAIL=1         — exit 1 for all data-returning commands (simulates ix failure)
+#   IX_MOCK_LOCATE_EXIT=N  — `ix locate` exits N *after* printing its body
+#                            (Ix#539: an unresolved target is a non-zero exit
+#                            with a usable payload, not an absent one)
 
 SUBCOMMAND="${1:-}"
 SELF_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
@@ -32,6 +35,17 @@ case "$SUBCOMMAND" in
     ;;
   locate)
     cat "${IX_MOCK_LOCATE_FILE:-${FX}/locate_resolved.json}"
+    # Ix#539 makes an unresolved target exit non-zero while still printing its
+    # body. Simulated separately from IX_MOCK_FAIL, which suppresses output too:
+    # the whole point is a failing exit code *with* usable output.
+    #
+    # `if`, never `[ -n "$V" ] && exit "$V"`. That form evaluates to status 1
+    # when V is unset, and as the last command in this branch it becomes the
+    # mock's own exit status -- so `ix locate` would exit 1 on every call, in
+    # every test. It is invisible precisely because the fix in this PR makes the
+    # hook tolerate a non-zero exit with a body, so the suite stays green while
+    # no longer testing what it claims to.
+    if [ -n "${IX_MOCK_LOCATE_EXIT:-}" ]; then exit "${IX_MOCK_LOCATE_EXIT}"; fi
     ;;
   overview)
     cat "${IX_MOCK_OVERVIEW_FILE:-${FX}/overview_normal.json}"

tests/test_hooks.sh

@@ -197,6 +197,17 @@ assert_log_contains() {
   pass "${_name}"
 }
 
+assert_log_not_contains() {
+  local _name="$1" _needle="$2"
+  if [ ! -f "${_IX_DEBUG_LOG:-}" ]; then
+    fail "${_name}" "debug log missing at ${_IX_DEBUG_LOG:-<unset>}"; return
+  fi
+  if grep -Fq -- "$_needle" "${_IX_DEBUG_LOG}"; then
+    fail "${_name}" "debug log unexpectedly contains '${_needle}'"; return
+  fi
+  pass "${_name}"
+}
+
 run_ix_hook_decide() {
   local _mode="$1" _content="$2"; shift 2
   _RC=0
@@ -546,6 +557,30 @@ run_hook ix-intercept.sh "${FX_IN}/grep_plain.json" \
   IX_MOCK_LOCATE_FILE="${FX_IX}/locate_candidates.json"
 assert_additional_context "intercept/medium confidence candidates augment" "[ix text + ix locate]"
 
+# ── Ix#539: `ix locate` exiting non-zero while still printing a body ──────────
+# An unresolved target is about to exit non-zero with its JSON payload intact.
+# The hook must keep using that payload, and must not record it as a locate
+# failure -- otherwise every symbol a user asks about that does not exist files
+# an error, burying the real failures.
+run_hook ix-intercept.sh "${FX_IN}/grep_plain.json" \
+  IX_MOCK_LOCATE_FILE="${FX_IX}/locate_candidates.json" \
+  IX_MOCK_LOCATE_EXIT=1
+assert_additional_context "intercept/non-zero locate still augments" "[ix text + ix locate]"
+
+run_hook_with_debug_log ix-intercept.sh "${FX_IN}/grep_plain.json" \
+  IX_MOCK_LOCATE_FILE="${FX_IX}/locate_candidates.json" \
+  IX_MOCK_LOCATE_EXIT=1
+assert_log_contains "intercept/non-zero locate with a body is a miss, not a failure" \
+  "MISS ix locate exited 1 with a body"
+
+# An empty body with a non-zero exit is still a genuine failure and must not be
+# swallowed by the same branch.
+run_hook_with_debug_log ix-intercept.sh "${FX_IN}/grep_plain.json" \
+  IX_MOCK_LOCATE_FILE=/dev/null \
+  IX_MOCK_LOCATE_EXIT=1
+assert_log_not_contains "intercept/non-zero locate with no body stays a failure" \
+  "MISS ix locate exited"
+
 # Glob → inventory → block when result set is manageable
 run_hook ix-intercept.sh "${FX_IN}/glob_path.json"
 assert_block_decision "intercept/glob pattern blocks" "Next: ix overview AuthService"