Does the New CLI Do the Same Job? An Output-Parity Gate Before Switching to Antigravity CLI

#!/usr/bin/env bash
# capture_golden.sh — freeze old-CLI artifacts as the golden baseline
set -euo pipefail
 
GOLDEN_DIR="golden/$(date +%Y%m%d)"
TASKS_DIR="parity_tasks"   # one prompt file per representative task
mkdir -p "$GOLDEN_DIR"
 
for task in "$TASKS_DIR"/*.txt; do
  name="$(basename "$task" .txt)"
  out="$GOLDEN_DIR/$name"
  mkdir -p "$out/files"
 
  # Run the old CLI non-interactively; isolate writes under out/files
  gemini run --prompt-file "$task" --workdir "$out/files" \
    > "$out/stdout.log" 2> "$out/stderr.log" || true
  echo "$?" > "$out/exit_code"
 
  # Record the file list and content hashes
  ( cd "$out/files" && find . -type f | sort > "../manifest.txt" )
  ( cd "$out/files" && find . -type f -exec sha256sum {} \; | sort > "../hashes.txt" )
  echo "captured: $name"
done
 
echo "golden fixed at $GOLDEN_DIR"

# normalize.py — reduce an artifact to a comparable canonical form
import re
import json
from pathlib import Path
 
# (1) Mask tokens that always change mechanically
VOLATILE = [
    (re.compile(r"\d{4}-\d{2}-\d{2}T[\d:]+(?:Z|[+\-]\d{2}:?\d{2})?"), "<TS>"),
    (re.compile(r"\brun[-_][0-9a-f]{6,}\b", re.I), "<RUN_ID>"),
    (re.compile(r"\b[0-9a-f]{40}\b"), "<SHA>"),
    (re.compile(r"\b\d+(?:\.\d+)?\s*(ms|s|sec)\b"), "<DUR>"),
]
 
def normalize_text(text: str) -> str:
    for pat, repl in VOLATILE:
        text = pat.sub(repl, text)
    # (2) Trim trailing whitespace and collapse blank-line runs
    text = "\n".join(line.rstrip() for line in text.splitlines())
    text = re.sub(r"\n{3,}", "\n\n", text)
    return text.strip()
 
def structural_signature(md: str) -> dict:
    # (3) Extract the skeleton, not the prose; wording can drift, skeleton holds
    body = re.sub(r"^---\n.*?\n---\n", "", md, flags=re.DOTALL)
    return {
        "h2": len(re.findall(r"^##\s", body, re.M)),
        "h3": len(re.findall(r"^###\s", body, re.M)),
        "code_blocks": body.count("```") // 2,
        "links": len(re.findall(r"\]\(", body)),
        "frontmatter_keys": sorted(
            re.findall(r"^(\w+):", md.split("---")[1], re.M)
        ) if "---" in md else [],
    }
 
if __name__ == "__main__":
    import sys, hashlib
    p = Path(sys.argv[1])
    raw = p.read_text(encoding="utf-8")
    print(json.dumps({
        "normalized_sha": hashlib.sha256(
            normalize_text(raw).encode()).hexdigest()[:16],
        "structure": structural_signature(raw),
    }, ensure_ascii=False, indent=2))

# parity_gate.py — decide go / no-go
import json, sys, subprocess
from pathlib import Path
 
def sig(path):
    out = subprocess.check_output(["python3", "normalize.py", str(path)])
    return json.loads(out)
 
def compare(golden_dir: Path, candidate_dir: Path) -> list[str]:
    findings = []
    for gfile in (golden_dir / "files").rglob("*"):
        if not gfile.is_file():
            continue
        rel = gfile.relative_to(golden_dir / "files")
        cfile = candidate_dir / "files" / rel
        if not cfile.exists():
            findings.append(f"BLOCK missing: {rel} was not generated by the new CLI")
            continue
        g, c = sig(gfile), sig(cfile)
        if g["structure"] != c["structure"]:
            findings.append(f"BLOCK structure: {rel} {g['structure']} -> {c['structure']}")
        elif g["normalized_sha"] != c["normalized_sha"]:
            findings.append(f"REVIEW prose: {rel} (skeleton matches; human check advised)")
    return findings
 
if __name__ == "__main__":
    findings = compare(Path(sys.argv[1]), Path(sys.argv[2]))
    blocks = [f for f in findings if f.startswith("BLOCK")]
    for f in findings:
        print(f)
    # Any BLOCK stops the cutover
    sys.exit(1 if blocks else 0)