// tests/lib/pre-existing.test.mjs
// [PRX] fix round 4.5b2 part B, Step 5: a finding on a line the range did not
// add or change is marked pre-existing (lib/review/review-finalize.mjs, from
// git through lib/review/pre-existing.mjs), and the verdict gate re-derives the
// mark from git: it never trusts it as written. A pre-existing MAJOR leaves the
// answer set; a BLOCKER or a security finding counts in full whatever the mark;
// every uncertain case (a renamed file, line 0, no scope_sha_start, a changed
// line, a line next to a pure deletion, an uncommitted file) counts as new.
// Tests run the CLIs (gate, finalize, fill-finding-ids, validator) in throwaway
// git repos with no hooks; `changedLineSets` is also read directly for the
// repo-config case. `keep:` cases hold at the base already and stay untagged.
// Each tagged gate case carries a Control: the same finding on an unchanged
// line exits 0, which only a gate that reads the mark can do.

import { after, test } from 'node:test';
import { strict as assert } from 'node:assert';
import { spawnSync } from 'node:child_process';
import { appendFileSync, existsSync, mkdirSync, mkdtempSync, readFileSync, rmSync, symlinkSync, writeFileSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { dirname, join } from 'node:path';
import { fileURLToPath, pathToFileURL } from 'node:url';
import { computeFindingId, computeFindingIds } from '../../lib/parsers/finding-id.mjs';
import { childEnv } from '../helpers/child-env.mjs';

const ROOT = join(dirname(fileURLToPath(import.meta.url)), '..', '..');
const GATE = join(ROOT, 'lib', 'review', 'verdict-gate.mjs');
const PRE = join(ROOT, 'lib', 'review', 'pre-existing.mjs');
const FINALIZE = join(ROOT, 'lib', 'review', 'review-finalize.mjs');
const FILL = join(ROOT, 'lib', 'review', 'fill-finding-ids.mjs');
const VALIDATOR = join(ROOT, 'lib', 'validators', 'review-validator.mjs');
const REVIEW_REL = '.claude/projects/2026-11-02-p/review.md';

// Loaded so that each new assertion fails on its own while the module is absent.
let preMod = {};
try {
  preMod = await import(pathToFileURL(PRE).href);
} catch (e) {
  if (existsSync(PRE)) throw e;
}

const made = [];
after(() => { for (const b of made) rmSync(b, { recursive: true, force: true }); });

function g(cwd, ...args) {
  const r = spawnSync('git', args, { cwd, encoding: 'utf8', env: childEnv() });
  if (r.status !== 0) throw new Error(`git ${args.join(' ')}: ${r.stderr}`);
  return r.stdout.trim();
}

function putIn(dir, rel, text) {
  mkdirSync(dirname(join(dir, rel)), { recursive: true });
  writeFileSync(join(dir, rel), text);
}

const parse = (r) => { try { return JSON.parse(r.stdout); } catch { return {}; } };
// Ten lines `export const <tag><n> = <n>;`; `changes` maps a line number to new text, or to null to remove it.
const ten = (tag, changes = {}) => Array.from({ length: 10 }, (_, i) => (i + 1 in changes ? changes[i + 1] : `export const ${tag}${i + 1} = ${i + 1};`))
  .filter((l) => l !== null).join('\n') + '\n';

/**
 * A throwaway repo. The start commit holds a.mjs, d.mjs and old.mjs (ten lines
 * each). `rounds` are later commits, each a map of path → text (null removes,
 * `{ mv: from }` renames). The default single round:
 *   - a.mjs line 3 changed;
 *   - d.mjs line 5 removed (a pure deletion: new lines 4 and 5 sit next to it);
 *   - old.mjs renamed to moved.mjs, unchanged;
 *   - n.mjs added.
 * `config` lines go into .git/config before the rounds are committed.
 */
function prxRepo({ config = [], rounds } = {}) {
  const base = mkdtempSync(join(tmpdir(), 'pre-existing-prx-'));
  made.push(base);
  const repo = join(base, 'repo');
  mkdirSync(repo, { recursive: true });
  mkdirSync(join(base, 'hooks-none'));
  g(repo, 'init', '-q', '-b', 'main');
  appendFileSync(join(repo, '.git', 'config'), '[user]\n\tname = Test\n\temail = test@example.invalid\n'
    + `[commit]\n\tgpgsign = false\n[core]\n\thooksPath = "${join(base, 'hooks-none')}"\n`);
  appendFileSync(join(repo, '.git', 'info', 'exclude'), '.claude/projects/\n');
  putIn(repo, 'a.mjs', ten('a'));
  putIn(repo, 'd.mjs', ten('d'));
  putIn(repo, 'old.mjs', ten('o'));
  g(repo, 'add', '-A');
  g(repo, 'commit', '-q', '-m', 'chore: start');
  const start = g(repo, 'rev-parse', 'HEAD');
  g(repo, 'checkout', '-q', '-b', 'feat');
  for (const c of config) g(repo, 'config', ...c);
  const plan = rounds ?? [{
    'a.mjs': ten('a', { 3: 'export const a3 = 33;' }),
    'd.mjs': ten('d', { 5: null }),
    'moved.mjs': { mv: 'old.mjs' },
    'n.mjs': 'export const n = 1;\n',
  }];
  const shas = [];
  plan.forEach((files, i) => {
    for (const [rel, text] of Object.entries(files)) {
      if (text === null) g(repo, 'rm', '-q', rel);
      else if (typeof text === 'object') g(repo, 'mv', text.mv, rel);
      else putIn(repo, rel, text);
    }
    g(repo, 'add', '-A');
    g(repo, 'commit', '-q', '-m', `feat: round ${i + 1}`);
    shas.push(g(repo, 'rev-parse', 'HEAD'));
  });
  const reviewPath = join(repo, ...REVIEW_REL.split('/'));
  return {
    repo, start, shas, end: shas.at(-1), reviewPath,
    write: (text) => putIn(repo, REVIEW_REL, text),
    read: () => readFileSync(reviewPath, 'utf8'),
    gate: () => spawnSync(process.execPath, [GATE, '--json', reviewPath, '--repo', repo], { encoding: 'utf8', env: childEnv() }),
    finalize: (extra = []) => spawnSync(process.execPath, [FINALIZE, '--review', reviewPath, '--repo', repo,
      '--project', dirname(reviewPath), '--round', '1', ...extra], { encoding: 'utf8', env: childEnv() }),
    fill: () => spawnSync(process.execPath, [FILL, reviewPath], { encoding: 'utf8', env: childEnv() }),
    validate: () => spawnSync(process.execPath, [VALIDATOR, '--strict', reviewPath], { encoding: 'utf8', env: childEnv() }),
  };
}

/**
 * A review_version 1.2 review of `start..end`. `findings` are
 * [{severity, file, line, rule_key?, engine?, pre_existing?, title?}]; ids are
 * computed over (file, line, rule_key) unless `ids` names them. `start: null`
 * writes `scope_sha_start: null`; `round`/`roundBase` add the round fields.
 */
function prxReview({ start, end, findings, verdict, ids, round, roundBase }) {
  const list = findings.map((f, i) => ({
    severity: f.severity, rule_key: f.rule_key ?? 'MISSING_TEST', ...(f.engine ? { engine: f.engine } : {}),
    file: f.file, line: f.line, title: f.title ?? `t${i + 1}`, detail: `d${i + 1}`, recommended_action: 'Add a test.',
    ...('pre_existing' in f ? { pre_existing: f.pre_existing } : {}),
  }));
  const computed = ids ?? computeFindingIds(list);
  list.forEach((f, i) => { f.id = computed[i]; });
  const ordered = list.map(({ id, ...rest }) => ({ id, ...rest }));
  const counts = { BLOCKER: 0, MAJOR: 0, MINOR: 0, SUGGESTION: 0 };
  for (const f of ordered) counts[f.severity] += 1;
  const v = verdict ?? (counts.BLOCKER > 0 ? 'BLOCK' : counts.MAJOR > 0 ? 'WARN' : 'ALLOW');
  const json = JSON.stringify({ verdict: v, counts, allow_blocked_by: [], findings: ordered }, null, 2);
  const sections = ['BLOCKER', 'MAJOR', 'MINOR', 'SUGGESTION'].map((sev) => {
    const of = ordered.filter((f) => f.severity === sev);
    if (of.length === 0) return '';
    return `## Findings (${sev})\n\n${of.map((f) => `### ${f.id}\n\n- **Rule:** \`${f.rule_key}\`\n- **Location:** \`${f.file}:${f.line}\`\n- **Title:** ${f.title}\n`).join('\n')}\n`;
  }).join('');
  const steps = ordered.filter((f) => f.severity === 'BLOCKER' || f.severity === 'MAJOR')
    .map((f, i) => `### Step R${i + 1}: fix ${f.title}\n\n- **Files:** \`${f.file}\`\n- **Source finding:** \`${f.id}\`\n- **Test first:** a test that fails today\n- **Verify:** re-run /trekreview\n- **On failure:** escalate\n`).join('\n');
  return `---
type: trekreview
review_version: "1.2"
task: "t"
slug: p
project_dir: .claude/projects/2026-11-02-p/
brief_path: .claude/projects/2026-11-02-p/brief.md
scope_sha_start: ${start === null ? 'null' : start}
scope_sha_end: ${end}
reviewed_files_count: 3
verdict: ${v}
${round ? `round: ${round}\nround_base: ${roundBase ?? 'null'}\n` : ''}findings:
${ordered.map((f) => `  - ${f.id}`).join('\n')}
---

# Review: t

## Executive Summary

x

## Coverage

| File | Treatment | Reason |
|------|-----------|--------|
| a.mjs | deep-review | default |

${sections}## Declined to Judge

None.

Trimmed: 0

## Remediation Summary

x

## Remediation Steps

${steps || 'None.\n'}
\`\`\`json
${json}
\`\`\`
`;
}

const jsonOf = (text) => JSON.parse(text.slice(text.lastIndexOf('```json\n') + 8, text.lastIndexOf('```')));

/** Write a one-finding WARN review of the fixture's range and run the gate on it. */
function gateOn(fx, finding, opts = {}) {
  fx.write(prxReview({ start: fx.start, end: fx.end, findings: [{ severity: 'MAJOR', ...finding }], ...opts }));
  return fx.gate();
}

function assertUnanswered(r) {
  assert.equal(r.status, 2, r.stdout + r.stderr);
  assert.match(String(parse(r).reason), /^review-unanswered:/, r.stdout);
}

function assertControl(fx, finding = { file: 'a.mjs', line: 7, pre_existing: true }) {
  const r = gateOn(fx, finding);
  assert.equal(r.status, 0, `Control: a MAJOR marked pre-existing on an unchanged line opens the gate: ${r.stdout}${r.stderr}`);
}

test('[PRX] a MAJOR outside the -U0 added or changed lines is marked pre-existing and leaves the answer set', () => {
  assert.ok(existsSync(FINALIZE), 'lib/review/review-finalize.mjs must exist');
  const fx = prxRepo();
  fx.write(prxReview({ start: fx.start, end: fx.end, findings: [{ severity: 'MAJOR', file: 'a.mjs', line: 7, title: 'An old defect' }] }));
  const f = fx.finalize();
  assert.equal(f.status, 0, f.stdout + f.stderr);
  const text = fx.read();
  const payload = jsonOf(text);
  assert.equal(payload.findings[0].pre_existing, true, text);
  assert.deepEqual(payload.pre_existing_counts, { BLOCKER: 0, MAJOR: 1, MINOR: 0, SUGGESTION: 0 });
  assert.equal(payload.findings[0].severity, 'MAJOR', 'the mark never lowers a finding');
  const pre = text.search(/^## Pre-existing\s*$/m);
  const declined = text.search(/^## Declined to Judge\s*$/m);
  assert.ok(pre !== -1 && pre < declined, `## Pre-existing stands just before ## Declined to Judge:\n${text}`);
  assert.ok(text.slice(pre, declined).includes('An old defect'), text.slice(pre, declined));
  assert.ok(!/^## Answers/m.test(text), 'no answer was written');
  const r = fx.gate();
  assert.equal(r.status, 0, r.stdout + r.stderr);
});

test('[PRX] a finding in a renamed file, on line 0, with no scope_sha_start, on a changed line or next to a pure deletion counts as new', () => {
  assert.equal(typeof preMod.changedLineSets, 'function', 'pre-existing.mjs exports changedLineSets');
  const fx = prxRepo();
  assertControl(fx);
  const cases = [
    ['a renamed file', { file: 'moved.mjs', line: 5, pre_existing: true }],
    ['line 0', { file: 'a.mjs', line: 0, pre_existing: true }],
    ['a changed line', { file: 'a.mjs', line: 3, pre_existing: true }],
    ['the line before a pure deletion', { file: 'd.mjs', line: 4, pre_existing: true }],
    ['the line after a pure deletion', { file: 'd.mjs', line: 5, pre_existing: true }],
    ['a new file', { file: 'n.mjs', line: 1, pre_existing: true }],
  ];
  for (const [what, finding] of cases) {
    const r = gateOn(fx, finding);
    assert.equal(r.status, 2, `${what}: ${r.stdout}${r.stderr}`);
    assert.match(String(parse(r).reason), /^review-unanswered:/, `${what}: ${r.stdout}`);
  }
  const none = gateOn(fx, { file: 'a.mjs', line: 7, pre_existing: true }, { start: null });
  assert.equal(none.status, 2, `no scope_sha_start: ${none.stdout}${none.stderr}`);
  assert.match(String(parse(none).reason), /^review-unanswered:/, none.stdout);
  // Control: a line well away from the deletion is still pre-existing (the file is not 'all').
  assertControl(fx, { file: 'd.mjs', line: 8, pre_existing: true });
});

test('[PRX] finalize marks none of the uncertain cases, and no finding in a file with uncommitted changes', () => {
  assert.ok(existsSync(FINALIZE), 'lib/review/review-finalize.mjs must exist');
  const fx = prxRepo();
  const findings = [
    { severity: 'MAJOR', file: 'moved.mjs', line: 5 },
    { severity: 'MAJOR', file: 'a.mjs', line: 3 },
    { severity: 'MAJOR', file: 'd.mjs', line: 4 },
    { severity: 'MAJOR', file: 'd.mjs', line: 5 },
    { severity: 'MINOR', file: 'a.mjs', line: 0 },
    { severity: 'MAJOR', file: 'd.mjs', line: 8 },
  ];
  fx.write(prxReview({ start: fx.start, end: fx.end, findings }));
  const f = fx.finalize();
  assert.equal(f.status, 0, f.stdout + f.stderr);
  assert.deepEqual(jsonOf(fx.read()).findings.map((x) => x.pre_existing), [false, false, false, false, false, true]);
  // An uncommitted change in d.mjs: its findings are not marked.
  putIn(fx.repo, 'd.mjs', ten('d', { 5: null, 9: 'export const d10 = 0;' }));
  fx.write(prxReview({ start: fx.start, end: fx.end, findings: [{ severity: 'MAJOR', file: 'd.mjs', line: 8 }] }));
  const u = fx.finalize();
  assert.equal(u.status, 0, u.stdout + u.stderr);
  assert.equal(jsonOf(fx.read()).findings[0].pre_existing, false, fx.read());
  // No scope_sha_start: nothing is marked.
  fx.write(prxReview({ start: null, end: fx.end, findings: [{ severity: 'MAJOR', file: 'a.mjs', line: 7 }] }));
  const n = fx.finalize();
  assert.equal(n.status, 0, n.stdout + n.stderr);
  assert.equal(jsonOf(fx.read()).findings[0].pre_existing, false, fx.read());
});

test('[PRX] in a round-2 review whose scope_sha_start is the run\'s start, a MAJOR on a line round 1 added counts as new', () => {
  assert.equal(typeof preMod.changedLineSets, 'function', 'pre-existing.mjs exports changedLineSets');
  const fx = prxRepo({ rounds: [
    { 'a.mjs': ten('a', { 5: 'export const a5 = 55;' }) },
    { 'a.mjs': ten('a', { 5: 'export const a5 = 55;', 9: 'export const a9 = 99;' }) },
  ] });
  const [round1] = fx.shas;
  const opts = { round: 2, roundBase: round1 };
  const r = gateOn(fx, { file: 'a.mjs', line: 5, pre_existing: true }, opts);
  assertUnanswered(r);
  // Control: an unchanged line of the same file is pre-existing in round 2.
  const c = gateOn(fx, { file: 'a.mjs', line: 7, pre_existing: true }, opts);
  assert.equal(c.status, 0, `Control: ${c.stdout}${c.stderr}`);
  // Finalize marks by the run range too, whatever --round-base says.
  fx.write(prxReview({ start: fx.start, end: fx.end, findings: [{ severity: 'MAJOR', file: 'a.mjs', line: 5 }], ...opts }));
  const f = fx.finalize(['--round-base', round1]);
  assert.equal(f.status, 0, f.stdout + f.stderr);
  assert.equal(jsonOf(fx.read()).findings[0].pre_existing, false, fx.read());
});

test('[PRX] a pre-existing security MAJOR (CODE_REVIEW_DEFECT from security-review) still exits 2 with review-unanswered:', () => {
  const fx = prxRepo();
  // Control: the same key from the code-review engine is pre-existing and opens the gate.
  assertControl(fx, { file: 'a.mjs', line: 7, rule_key: 'CODE_REVIEW_DEFECT', engine: 'code-review', pre_existing: true });
  const r = gateOn(fx, { file: 'a.mjs', line: 7, rule_key: 'CODE_REVIEW_DEFECT', engine: 'security-review', pre_existing: true });
  assertUnanswered(r);
});

test('[PRX] after finalize every id is the computed one and the gate reads the file', () => {
  assert.ok(existsSync(FINALIZE), 'lib/review/review-finalize.mjs must exist');
  const fx = prxRepo();
  const findings = [
    { severity: 'MAJOR', file: 'a.mjs', line: 7, title: 'An old defect' },
    { severity: 'MINOR', file: 'a.mjs', line: 3, title: 'A new nit' },
  ];
  // The MAJOR carries an id over an old line (8): finalize recomputes it.
  const stale = computeFindingId('a.mjs', 8, 'MISSING_TEST');
  const good = computeFindingId('a.mjs', 3, 'MISSING_TEST');
  fx.write(prxReview({ start: fx.start, end: fx.end, findings, ids: [stale, good] }));
  const f = fx.finalize();
  assert.equal(f.status, 0, f.stdout + f.stderr);
  const text = fx.read();
  const want = computeFindingId('a.mjs', 7, 'MISSING_TEST');
  assert.deepEqual(jsonOf(text).findings.map((x) => x.id), [want, good]);
  assert.ok(!text.includes(stale), `no stale id is left anywhere:\n${text}`);
  assert.ok(text.includes(`  - ${want}\n`) && text.includes(`### ${want}\n`) && text.includes(`**Source finding:** \`${want}\``), text);
  const fill = fx.fill();
  assert.equal(fill.status, 0, `fill-finding-ids has nothing left to fill: ${fill.stdout}${fill.stderr}`);
  assert.equal(fx.read(), text, 'fill-finding-ids leaves the finalized file unchanged');
  const v = fx.validate();
  assert.equal(v.status, 0, `review-validator --strict: ${v.stdout}${v.stderr}`);
  const r = fx.gate();
  assert.equal(r.status, 0, r.stdout + r.stderr);
  assert.doesNotMatch(String(parse(r).reason), /differ/, r.stdout);
});

test('[PRX] a forged pre_existing mark on an added line still needs an answer', () => {
  const fx = prxRepo();
  assertControl(fx);
  assertUnanswered(gateOn(fx, { file: 'a.mjs', line: 3, pre_existing: true }));
  assertUnanswered(gateOn(fx, { file: 'n.mjs', line: 1, pre_existing: true }));
  // A path the diff cannot name the same way is never pre-existing.
  assertUnanswered(gateOn(fx, { file: './a.mjs', line: 3, pre_existing: true }));
});

test('[PRX] a path or line that is not in the tree at scope_sha_end counts as new, at the gate and in finalize', () => {
  assert.ok(existsSync(FINALIZE), 'lib/review/review-finalize.mjs must exist');
  // The default round plus a new sub/x.mjs (ten lines). a.mjs has ten lines at the end.
  const fx = prxRepo({ rounds: [{
    'a.mjs': ten('a', { 3: 'export const a3 = 33;' }),
    'd.mjs': ten('d', { 5: null }),
    'moved.mjs': { mv: 'old.mjs' },
    'n.mjs': 'export const n = 1;\n',
    'sub/x.mjs': ten('x'),
  }] });
  // Control: the last line of a.mjs is in the file and unchanged, so it is pre-existing.
  assertControl(fx, { file: 'a.mjs', line: 10, pre_existing: true });
  const cases = [
    ['a case variant of a changed file (the disk may be case-insensitive)', { file: 'A.mjs', line: 3 }],
    ['a file missing at scope_sha_end', { file: 'zzz.mjs', line: 5 }],
    ['a subdirectory-relative path to the added sub/x.mjs', { file: 'x.mjs', line: 3 }],
    ['a case variant of the added sub/x.mjs', { file: 'Sub/x.mjs', line: 3 }],
    ['a line past the end of the file', { file: 'a.mjs', line: 500 }],
    ['the line just past the end of the file', { file: 'a.mjs', line: 11 }],
  ];
  for (const [what, finding] of cases) {
    const r = gateOn(fx, { ...finding, pre_existing: true });
    assert.equal(r.status, 2, `${what}: ${r.stdout}${r.stderr}`);
    assert.match(String(parse(r).reason), /^review-unanswered:/, `${what}: ${r.stdout}`);
  }
  const findings = [...cases.map(([, f]) => ({ severity: 'MAJOR', ...f })), { severity: 'MAJOR', file: 'a.mjs', line: 10 }];
  fx.write(prxReview({ start: fx.start, end: fx.end, findings }));
  const f = fx.finalize();
  assert.equal(f.status, 0, f.stdout + f.stderr);
  const marks = jsonOf(fx.read()).findings.map((x) => `${x.file}:${x.line}=${x.pre_existing}`);
  assert.deepEqual(marks, ['A.mjs:3=false', 'zzz.mjs:5=false', 'x.mjs:3=false', 'Sub/x.mjs:3=false',
    'a.mjs:500=false', 'a.mjs:11=false', 'a.mjs:10=true']);
});

test('[PRX] a symlink to a file the range changed is not a regular file: a finding through it counts as new', () => {
  assert.ok(existsSync(FINALIZE), 'lib/review/review-finalize.mjs must exist');
  // The fixture's own range is not used: the run starts at a commit that adds
  // lnk.mjs -> a.mjs, and ends at one that changes line 1 of a.mjs. The link is
  // unchanged in the range, so only the tree mode at the end tells it apart.
  // Line 1 is cited because the link's blob ("a.mjs") is one line long.
  const fx = prxRepo();
  symlinkSync('a.mjs', join(fx.repo, 'lnk.mjs'));
  g(fx.repo, 'add', '--', 'lnk.mjs');
  g(fx.repo, 'commit', '-q', '-m', 'chore: link');
  const start = g(fx.repo, 'rev-parse', 'HEAD');
  g(fx.repo, 'branch', '-f', 'main', start);
  assert.equal(g(fx.repo, 'ls-tree', start, '--', 'lnk.mjs').split(' ')[0], '120000', 'lnk.mjs is committed as a symlink');
  putIn(fx.repo, 'a.mjs', ten('a', { 1: 'export const a1 = 11;' }));
  g(fx.repo, 'add', '--', 'a.mjs');
  g(fx.repo, 'commit', '-q', '-m', 'feat: change a.mjs line 1');
  const end = g(fx.repo, 'rev-parse', 'HEAD');
  const range = { start, end };
  // Control: an unchanged line of a.mjs is pre-existing in this range.
  const c = gateOn(fx, { file: 'a.mjs', line: 7, pre_existing: true }, range);
  assert.equal(c.status, 0, `Control: ${c.stdout}${c.stderr}`);
  // Control: the changed line through its real path counts as new.
  assertUnanswered(gateOn(fx, { file: 'a.mjs', line: 1, pre_existing: true }, range));
  assertUnanswered(gateOn(fx, { file: 'lnk.mjs', line: 1, pre_existing: true }, range));
  fx.write(prxReview({ ...range, findings: [
    { severity: 'MAJOR', file: 'lnk.mjs', line: 1 },
    { severity: 'MAJOR', file: 'a.mjs', line: 7 },
  ] }));
  const f = fx.finalize();
  assert.equal(f.status, 0, f.stdout + f.stderr);
  const marks = jsonOf(fx.read()).findings.map((x) => `${x.file}:${x.line}=${x.pre_existing}`);
  assert.deepEqual(marks, ['lnk.mjs:1=false', 'a.mjs:7=true']);
});

test('[PRX] repo diff config does not change the line sets', () => {
  assert.equal(typeof preMod.changedLineSets, 'function', 'pre-existing.mjs exports changedLineSets');
  const view = (s) => ({
    ok: s.ok,
    files: Object.fromEntries([...s.files].filter(([, v]) => v === 'all' || v.size > 0)
      .map(([k, v]) => [k, v === 'all' ? 'all' : [...v].sort((x, y) => x - y)]).sort()),
    renamed: [...s.renamed].sort(),
  });
  const want = { ok: true, files: { 'a.mjs': [3], 'd.mjs': [4, 5], 'n.mjs': 'all' }, renamed: ['moved.mjs', 'old.mjs'] };
  const plain = prxRepo();
  assert.deepEqual(view(preMod.changedLineSets(plain.repo, plain.start, plain.end)), want);
  const fx = prxRepo({ config: [['diff.renames', 'false'], ['color.diff', 'always'], ['diff.noprefix', 'true']] });
  assert.deepEqual(view(preMod.changedLineSets(fx.repo, fx.start, fx.end)), want);
  assertControl(fx);
  assertUnanswered(gateOn(fx, { file: 'moved.mjs', line: 5, pre_existing: true }));
  assertUnanswered(gateOn(fx, { file: 'a.mjs', line: 3, pre_existing: true }));
});

test('keep: a pre-existing BLOCKER still exits 1', () => {
  const fx = prxRepo();
  fx.write(prxReview({ start: fx.start, end: fx.end, findings: [{ severity: 'BLOCKER', file: 'a.mjs', line: 7, pre_existing: true }] }));
  const r = fx.gate();
  assert.equal(r.status, 1, r.stdout + r.stderr);
});

test('keep: the verdict gate accepts the pre_existing field without exit 2', () => {
  const fx = prxRepo();
  fx.write(prxReview({ start: fx.start, end: fx.end, findings: [
    { severity: 'MINOR', file: 'a.mjs', line: 7, pre_existing: true },
    { severity: 'MINOR', file: 'a.mjs', line: 3, pre_existing: false },
  ] }));
  const r = fx.gate();
  assert.equal(r.status, 0, r.stdout + r.stderr);
});