fix: follow a replaced inputFileSystem when purging in watch - #21643

#!/bin/bash
set -eu

printf '%s\n' '--- target test ---'
cat -n test/WatchInputFileSystem.test.js | sed -n '180,255p'

printf '%s\n' '--- watcher implementation references ---'
rg -n -C 4 'class NodeWatchFileSystem|watch\(|close\(' lib/node/NodeWatchFileSystem.js test/WatchInputFileSystem.test.js

#!/bin/bash
set -eu

printf '%s\n' '--- test setup and watch-error controls ---'
cat -n test/WatchInputFileSystem.test.js | sed -n '1,180p'
rg -n -C 5 'watchFileSystem|watch\([^;]*err|callback\(.*err|watch\(\{' lib test | head -n 240

printf '%s\n' '--- compiler watch implementation ---'
rg -n -C 8 'watch\(watchOptions|watch\(watchOptions|class Watching|watchFileSystem\.watch|callback\(err' lib/Compiler.js lib/Watching.js lib

#!/bin/bash
set -eu

printf '%s\n' '--- Compiler.watch ---'
cat -n lib/Compiler.js | sed -n '536,558p'

printf '%s\n' '--- Watching lifecycle and watch error handling ---'
cat -n lib/Watching.js | sed -n '28,190p'
cat -n lib/Watching.js | sed -n '190,360p'
cat -n lib/Watching.js | sed -n '360,520p'

printf '%s\n' '--- NodeWatchFileSystem watch return and close contract ---'
cat -n lib/node/NodeWatchFileSystem.js | sed -n '30,170p'

#!/bin/bash
set -eu

printf '%s\n' '--- Watching.close implementation ---'
cat -n lib/Watching.js | sed -n '477,590p'

printf '%s\n' '--- tests that force watch or watchRun errors ---'
rg -n -C 8 'watchRun|watchFileSystem\s*=|new NodeWatchFileSystem|done\(err\).*close|close\(\(\).*done' test | head -n 260

printf '%s\n' '--- watch callback type and all NodeWatchFileSystem callback error paths ---'
rg -n -C 5 'WatchMethod|callback\(err|callback\(null' lib/util/fs.d.ts lib/util/fs.js lib/node/NodeWatchFileSystem.js

#!/bin/bash
set -eu

python3 - <<'PY'
from pathlib import Path

test = Path("test/WatchInputFileSystem.test.js").read_text()
watching = Path("lib/Watching.js").read_text()
node_watch = Path("lib/node/NodeWatchFileSystem.js").read_text()

checks = {
    "test currently completes the error branch directly": (
        "if (err) return done(err);" in test
    ),
    "Watching forwards watch errors to the handler": (
        "if (err) {" in watching
        and "return this.handler(err);" in watching
    ),
    "Watching.close closes the active watcher before its callback": (
        "if (this.watcher) {" in watching
        and "this.watcher.close();" in watching
        and "this._closeCallbacks = [];" in watching
    ),
    "NodeWatchFileSystem.close closes the underlying watcher": (
        "this.watcher.close();" in node_watch
        and "this.watcher = null;" in node_watch
    ),
}

for name, passed in checks.items():
    print(f"{'PASS' if passed else 'FAIL'}: {name}")

assert all(checks.values())
print("Conclusion: an error delivered to the test callback can be followed by Watching.close(), and close performs watcher cleanup before invoking its close callback.")
PY

#!/bin/bash
set -euo pipefail

ast-grep outline test/WatchInputFileSystem.test.js --items all --type function

rg -n -C 6 \
  'jest\.setTimeout|testTimeout|15000|setTimeout' \
  test/WatchInputFileSystem.test.js package.json .

#!/bin/bash
set -euo pipefail

printf '%s\n' '--- test file timeout-related lines ---'
rg -n -C 8 'jest\.setTimeout|testTimeout|15000|setTimeout|after(All|Each)|watcher\.close|close\(' test/WatchInputFileSystem.test.js

printf '%s\n' '--- repository Jest configuration ---'
rg -n -C 5 'testTimeout|setTimeout|jest\.setTimeout|slowTestThreshold|testMatch|testRegex' \
  package.json \
  jest.config.* \
  config \
  test 2>/dev/null | head -n 300

printf '%s\n' '--- relevant test block ---'
sed -n '110,190p' test/WatchInputFileSystem.test.js

#!/bin/bash
set -euo pipefail

printf '%s\n' '--- complete test setup and affected tests ---'
sed -n '1,270p' test/WatchInputFileSystem.test.js

printf '%s\n' '--- watcher close implementation and related tests ---'
rg -n -C 8 'class .*Watcher|close\(callback|close\(.*callback|watcher.*close|Watching.*close' lib test | head -n 400

printf '%s\n' '--- Jest timeout semantics in repository configuration ---'
sed -n '1,45p' jest.config.js
rg -n -C 4 'WatchInputFileSystem|testTimeout|jest\.setTimeout' test/WatchInputFileSystem.test.js test/setupTestFramework.js jest.config.js package.json

#!/bin/bash
set -euo pipefail

sed -n '477,565p' lib/Watching.js
sed -n '60,90p' lib/MultiWatching.js
sed -n '1465,1505p' lib/Compiler.js