server.peers.subscribe is attacker-controlled data: ParsePeers assumed
the standard [ip, hostname, [features...]] shape and threw on anything
else (non-array response, wrong element types), and GetString() on a
JSON string containing invalid UTF-8 bytes threw InvalidOperationException
instead of failing to parse — both found by fuzzing. Any unexpected
shape or unparseable string now degrades to "no usable data" instead of
propagating an exception into the sync/discovery path.
CheckAsync built its own HttpClient inline, so nothing beyond tag
parsing was testable without hitting the real GitHub API. Added an
internal CheckAsync(currentVersion, HttpMessageHandler, ct) overload
(the public method now delegates to it) as a seam for a stub handler,
and tests for the full best-effort matrix: newer/equal/older/unparseable
tag, missing html_url, HTTP error status, malformed JSON, a thrown
HttpRequestException, and an unparseable local version — all of which
must resolve to null or the correct LatestRelease, never throw.
DispatchLine's ArrayPool-copy path (for a JSON-RPC line spanning
multiple PipeReader segments) only ran for small responses in existing
tests, which stay single-segment. A 256 KB fake response forces the
multi-segment branch and verifies the payload still arrives intact.
ElectrumClient, WalletSynchronizer, TransactionInspector, CertificatePinStore
and peer discovery went from 0% coverage to close to full coverage, all
against the fake ElectrumX server:
- ElectrumClient: request/response correlation under load, server errors,
notifications, disconnection, cancellation, SSL handshake with TOFU pinning.
- WalletSynchronizer: gap-limit scanning, UTXO/history reconstruction,
unconfirmed/immature balances, busy-retry, disk-cache reuse, and the
security-critical path where a lying server fails Merkle verification and
the sync must abort.
- TransactionInspector: fee calculation from resolved inputs, mine/theirs
attribution, RBF flag, coinbase handling, degraded paths when a previous
transaction can't be resolved.
- CertificatePinStore: TOFU pin/match/mismatch/reset, corrupted-file fallback.
- ServerRegistry: peer discovery and persistence via DiscoverAsync.
- UpdateChecker: release-tag parsing and semver comparison.
Real loopback TCP socket speaking newline-delimited JSON-RPC 2.0, optionally
TLS with a self-signed certificate, with per-method handlers and call
counters. Lets ElectrumClient, WalletSynchronizer, TransactionInspector, and
CertificatePinStore be exercised against the same code paths used in
production instead of being mocked.
Also exposes UpdateChecker's tag-parsing logic internally so its version
comparison can be tested without a real GitHub API call.
Translate every Italian /// XML doc comment, <!-- --> XAML comment, and
// inline comment to English across all source files (Core, App, tests).
Add the language policy to CLAUDE.md (conversation Italian; all code
and docs English). Update one test assertion that checked an Italian
exception message that was also translated.
davide