refactor(qbittorrent-e2e): introduce PayloadSize and PieceLength newtypes

Replace the two bare usize constants PAYLOAD_SIZE_BYTES and
TORRENT_PIECE_LENGTH in filesystem_setup.rs with PayloadSize and
PieceLength newtypes. Promote the constants to these types using const fn
constructors, and update build_payload_fixture and build_torrent_fixture
to accept the typed values. The inner usize is extracted just before the
lower-level torrent_artifacts helpers that still work with primitives.

Author: josecelano

src/console/ci/qbittorrent/filesystem_setup.rs

@@ -35,7 +35,7 @@ use anyhow::Context;
 use super::qbittorrent_client::QbittorrentCredentials;
 use super::qbittorrent_config::QbittorrentConfigBuilder;
 use super::scenario_steps::{build_payload_fixture, build_torrent_fixture};
-use super::types::{ComposeProjectName, ContainerPath, Deadline, FileName, PollInterval};
+use super::types::{ComposeProjectName, ContainerPath, Deadline, FileName, PayloadSize, PieceLength, PollInterval};
 use super::workspace::{
     EphemeralWorkspace, PeerConfig, PermanentWorkspace, PreparedWorkspace, SharedFixtures, TimingConfig, TorrentFixture,
     TrackerFilesystem, WorkspaceResources,
@@ -46,8 +46,8 @@ const SEEDER_PASSWORD: &str = "seeder-pass";
 const LEECHER_PASSWORD: &str = "leecher-pass";
 const PAYLOAD_FILE_NAME: &str = "payload.bin";
 const TORRENT_FILE_NAME: &str = "payload.torrent";
-const PAYLOAD_SIZE_BYTES: usize = 1024 * 1024;
-const TORRENT_PIECE_LENGTH: usize = 16 * 1024;
+const PAYLOAD_SIZE_BYTES: PayloadSize = PayloadSize::new(1024 * 1024);
+const TORRENT_PIECE_LENGTH: PieceLength = PieceLength::new(16 * 1024);
 const QBITTORRENT_DOWNLOADS_PATH: &str = "/downloads";
 const TORRENT_POLL_INTERVAL: Duration = Duration::from_millis(500);
 const LOGIN_POLL_INTERVAL: Duration = Duration::from_secs(1);

src/console/ci/qbittorrent/scenario_steps/fixtures/build_payload_fixture.rs

@@ -1,4 +1,5 @@
 use super::super::super::torrent_artifacts::build_payload_bytes;
+use super::super::super::types::PayloadSize;
 
 /// In-memory payload fixture used to generate torrent metadata and integrity checks.
 pub struct GeneratedPayload {
@@ -8,8 +9,8 @@ pub struct GeneratedPayload {
 /// Builds deterministic payload bytes for the E2E scenario.
 ///
 /// The generated payload is stable for a given size, which keeps test behavior reproducible.
-pub fn build_payload_fixture(payload_size_bytes: usize) -> GeneratedPayload {
+pub fn build_payload_fixture(payload_size_bytes: PayloadSize) -> GeneratedPayload {
     GeneratedPayload {
-        bytes: build_payload_bytes(payload_size_bytes),
+        bytes: build_payload_bytes(payload_size_bytes.as_usize()),
     }
 }

src/console/ci/qbittorrent/scenario_steps/fixtures/build_torrent_fixture.rs

@@ -1,6 +1,7 @@
 use anyhow::Context;
 
 use super::super::super::torrent_artifacts::build_torrent_bytes;
+use super::super::super::types::PieceLength;
 use super::build_payload_fixture::GeneratedPayload;
 
 /// In-memory `.torrent` fixture generated from a payload fixture.
@@ -17,9 +18,9 @@ pub fn build_torrent_fixture(
     payload: &GeneratedPayload,
     payload_name: &str,
     announce_url: &str,
-    piece_length: usize,
+    piece_length: PieceLength,
 ) -> anyhow::Result<GeneratedTorrent> {
-    let bytes = build_torrent_bytes(&payload.bytes, payload_name, announce_url, piece_length)
+    let bytes = build_torrent_bytes(&payload.bytes, payload_name, announce_url, piece_length.as_usize())
         .context("failed to build torrent fixture bytes from payload fixture")?;
 
     Ok(GeneratedTorrent { bytes })

src/console/ci/qbittorrent/types.rs

@@ -443,3 +443,43 @@ impl<'de> serde::Deserialize<'de> for TorrentHash {
         Ok(Self(value))
     }
 }
+
+/// The total byte size of a test payload used in the E2E torrent scenario.
+///
+/// Distinct from [`PieceLength`] to prevent an accidental swap of the two
+/// `usize` torrent-construction arguments.
+#[derive(Debug, Clone, Copy)]
+pub(crate) struct PayloadSize(usize);
+
+impl PayloadSize {
+    /// Creates a new [`PayloadSize`] from a byte count.
+    pub(crate) const fn new(bytes: usize) -> Self {
+        Self(bytes)
+    }
+
+    /// Returns the byte count as a `usize`.
+    #[must_use]
+    pub(crate) fn as_usize(self) -> usize {
+        self.0
+    }
+}
+
+/// The piece length for a torrent, in bytes.
+///
+/// Distinct from [`PayloadSize`] to prevent an accidental swap of the two
+/// `usize` torrent-construction arguments.
+#[derive(Debug, Clone, Copy)]
+pub(crate) struct PieceLength(usize);
+
+impl PieceLength {
+    /// Creates a new [`PieceLength`] from a byte count.
+    pub(crate) const fn new(bytes: usize) -> Self {
+        Self(bytes)
+    }
+
+    /// Returns the piece length as a `usize`.
+    #[must_use]
+    pub(crate) fn as_usize(self) -> usize {
+        self.0
+    }
+}