按规划继续工作

结论：将现有负向 G-code fixture 纳入 upstream rs274 -g side-by-side 基线，校验错误文本和 absent canonical 事件约束，继续保持解释器语义来源于 LinuxCNC。

wasm-port/tools/verify_native_linuxcnc_fixture_baseline.sh

@@ -5,6 +5,8 @@ ROOT_DIR="$(cd "$(dirname "$0")/.." && pwd)"
 UPSTREAM_RS274="$ROOT_DIR/../linuxcnc/bin/rs274"
 GCODE_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/gcode"
 CANON_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/canon"
+GCODE_ERROR_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/gcode_errors"
+CANON_ERROR_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/canon_errors"
 
 FIXTURES=(
   minimal_linear
@@ -37,6 +39,18 @@ FIXTURES=(
   tool_reload
 )
 
+ERROR_FIXTURES=(
+  arc_radius_mismatch
+  arc_zero_radius
+  cutter_comp_plane_change
+  g1_zero_feed
+  g53_incremental
+  namedparam_readonly
+  numbered_param_readonly
+  tool_length_offset_not_found
+  tool_not_found
+)
+
 if [[ ! -x "$UPSTREAM_RS274" ]]; then
   echo "missing upstream rs274 executable: $UPSTREAM_RS274" >&2
   exit 1
@@ -807,6 +821,13 @@ filter_to_expected_event_keys() {
   ' "$expected_norm" -
 }
 
+normalize_absent_standalone_event() {
+  local absent_line="$1"
+  local event="${absent_line#absent=canon_event=}"
+
+  printf 'canon_event=%s\n' "$event" | normalize_standalone_events
+}
+
 for name in "${FIXTURES[@]}"; do
   gcode_file="$GCODE_FIXTURE_DIR/$name.ngc"
   expected_file="$CANON_FIXTURE_DIR/$name.events"
@@ -903,4 +924,53 @@ for name in "${FIXTURES[@]}"; do
   fi
 done
 
+for name in "${ERROR_FIXTURES[@]}"; do
+  gcode_file="$GCODE_ERROR_FIXTURE_DIR/$name.ngc"
+  expected_file="$CANON_ERROR_FIXTURE_DIR/$name.expected"
+  native_raw="$TMP_DIR/$name.error.rs274.raw"
+  native_norm="$TMP_DIR/$name.error.rs274.normalized"
+
+  if [[ ! -f "$gcode_file" ]]; then
+    echo "missing negative G-code fixture: $gcode_file" >&2
+    exit 1
+  fi
+
+  if [[ ! -f "$expected_file" ]]; then
+    echo "missing negative expected fixture: $expected_file" >&2
+    exit 1
+  fi
+
+  set +e
+  "$UPSTREAM_RS274" -g "$gcode_file" > "$native_raw" 2>&1
+  rs274_rc=$?
+  set -e
+
+  if [[ "$rs274_rc" == "0" ]]; then
+    echo "upstream rs274 unexpectedly succeeded for negative fixture: $name" >&2
+    sed -n '1,160p' "$native_raw" >&2
+    exit 1
+  fi
+
+  normalize_upstream_rs274_output < "$native_raw" > "$native_norm"
+
+  while IFS= read -r expected_line; do
+    [[ -z "$expected_line" ]] && continue
+    if [[ "$expected_line" == error_text=* ]]; then
+      expected_error="${expected_line#error_text=}"
+      if ! grep -Fq "$expected_error" "$native_raw"; then
+        echo "missing upstream rs274 error text for fixture $name: $expected_error" >&2
+        sed -n '1,160p' "$native_raw" >&2
+        exit 1
+      fi
+    elif [[ "$expected_line" == absent=canon_event=* ]]; then
+      absent_norm="$(normalize_absent_standalone_event "$expected_line")"
+      if grep -Fxq "$absent_norm" "$native_norm"; then
+        echo "unexpected upstream rs274 event for fixture $name: $absent_norm" >&2
+        sed -n '1,160p' "$native_raw" >&2
+        exit 1
+      fi
+    fi
+  done < "$expected_file"
+done
+
 echo "native LinuxCNC fixture baseline validation complete"