test: replace tokio-current-thread alpha with tokio LocalSet by anikettuli · Pull Request #971 · Stremio/stremio-core

anikettuli · 2026-04-20T05:03:50Z

Summary

Replaces the deprecated tokio-current-thread = "=0.2.0-alpha.1" dev-dep with tokio::task::LocalSet from the stable tokio crate already in the workspace.

Why this change

tokio-current-thread is a pre-1.0 tokio crate — its final release is an alpha from 2018. It has been effectively abandoned for ~8 years, yet the pin =0.2.0-alpha.1 carried forward because the test harness (src/unit_tests/env.rs) needed a single-threaded executor that could drain !Send futures before returning.

Modern tokio provides exactly that capability via tokio::task::LocalSet. Migrating removes a zombie dep, keeps the toolchain on supported crates, and shrinks the transitive dev-dep graph (no more tokio-executor, crossbeam-channel, crossbeam-utils, cfg-if pulled in transitively through this path).

Effect

One fewer abandoned dependency in the dev-dep graph.
Shrinks Cargo.lock by 4 transitive entries (~60 line removal).
No runtime behavior change in the published library; this is test infrastructure only. Test semantics (spawn-then-drain, two-phase state + event-loop separation) are preserved.
Unblocks modernizing the Env trait's concurrency docs to reference spawn_local directly.

Changes

`src/unit_tests/env.rs`

Two public helpers in the TestEnv harness:

TestEnv::run(runnable) — previously tokio_current_thread::block_on_all(future::lazy(|_| runnable())). Now builds a current-thread tokio runtime + LocalSet, runs the closure inside local.block_on, then drives the LocalSet to completion with rt.block_on(local). That last call preserves the key block_on_all semantic: spawned !Send futures finish before run returns.
TestEnv::run_with_runtime(rx, runtime, runnable) — originally two successive block_on_all calls. Now two successive LocalSet::block_on + rt.block_on(local) pairs named phase1 / phase2, preserving the original contract that Phase 1 (state capture + runnable + any effects it spawns) drains fully before Phase 2 (event collection + runtime close) starts.

Env impl:

exec_concurrent / exec_sequential: tokio_current_thread::spawn(future) → tokio::task::spawn_local(future). Every call site is (still) reached from within a LocalSet::block_on frame, which is the contract spawn_local expects.

`Cargo.toml`

Dropped tokio-current-thread = "=0.2.0-alpha.1" from [dev-dependencies]. The workspace's existing tokio = { version = "1.12", features = ["rt", "macros"] } already provides LocalSet and spawn_local.

`Cargo.lock`

Regenerated: removes tokio-current-thread, tokio-executor, crossbeam-channel, crossbeam-utils, and the cfg-if copy they pulled in.

Public API / contract

Zero changes to:

Storage keys (src/constants.rs:10)
WASM exports (stremio-core-web/src/stremio_core_web.rs:83-348)
Msg / Action / Event variants
Deep-link URL grammar
Serialized JSON field names

Test plan

Verified locally (Rust 1.85.1 stable-x86_64-pc-windows-gnu):

cargo test -p stremio-core --lib — 202 passed, 0 failed
cargo test -p stremio-watched-bitfield — 7 passed, 0 failed
cargo clippy --all --no-deps -- -D warnings — clean (the remaining future-incompat-report note is about wasm-bindgen 0.2.78; that's what build: upgrade wasm-bindgen 0.2.78 → 0.2.118 and WASM deps #969 upgrades)
cargo fmt --check — clean

`tokio-current-thread = "=0.2.0-alpha.1"` is a pre-1.0 tokio crate that has been deprecated for years. It was still pinned to an alpha here because the test harness (src/unit_tests/env.rs) relies on a single-threaded executor that drains spawned `!Send` futures before returning. Modern tokio provides the same capability via `tokio::task::LocalSet`: - `tokio_current_thread::block_on_all(future)` replaced with a `Builder::new_current_thread` runtime + two-phase `LocalSet` drives that preserve the original two-step semantic of `run_with_runtime` (state capture + runnable, then event loop + runtime close, each draining spawn_local tasks between phases). - `tokio_current_thread::spawn(future)` replaced with `tokio::task::spawn_local(future)` in the `Env::exec_{concurrent,sequential}` impls. Any call is still scoped inside a `LocalSet::block_on`, matching the behavior the old spawn relied on. No production code changes. No Env trait surface change. No behavior change observable to the library's public API; test semantics (drain-between-phases) are preserved. Removed: - `tokio-current-thread = "=0.2.0-alpha.1"` from `[dev-dependencies]`. - Transitive dev deps no longer needed: `tokio-executor`, `crossbeam-channel`, `crossbeam-utils`, `cfg-if` (removed by `cargo`, reflected in `Cargo.lock`). Verified locally (Rust 1.85.1 stable-x86_64-pc-windows-gnu): cargo test -p stremio-core --lib -> 202 passed, 0 failed cargo clippy --all --no-deps -D warnings -> clean cargo fmt --check -> clean

github-actions · 2026-04-20T05:04:01Z

stremio-core-web prebuild

Prebuild artifact published by the Build workflow for branch claude/remove-tokio-current-thread.

Paste one of these into stremio-web's package.json and run pnpm install to wire this prebuild into a corresponding stremio-web PR:

Release

"@stremio/stremio-core-web": "https://stremio.github.io/stremio-core/stremio-core-web/claude/remove-tokio-current-thread/stremio-stremio-core-web-0.56.3.tgz"

Dev

"@stremio/stremio-core-web": "https://stremio.github.io/stremio-core/stremio-core-web/claude/remove-tokio-current-thread/dev/stremio-stremio-core-web-0.56.3.tgz"

Copilot

Pull request overview

Updates the test harness to use stable Tokio primitives by replacing the deprecated tokio-current-thread dev-dependency with tokio::task::LocalSet on a current-thread runtime, while preserving the “spawn then drain before returning” behavior needed for !Send futures.

Changes:

Reworked TestEnv::run / TestEnv::run_with_runtime to drive LocalSet on a current-thread Tokio runtime and drain spawned local tasks before returning.
Updated TestEnv’s Env implementation to use tokio::task::spawn_local instead of tokio_current_thread::spawn.
Removed tokio-current-thread from dev-dependencies and refreshed Cargo.lock accordingly.

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/unit_tests/env.rs	Migrates test executor plumbing to `tokio::runtime::Builder::new_current_thread` + `LocalSet` and switches task spawning to `spawn_local`.
Cargo.toml	Drops deprecated `tokio-current-thread` from `[dev-dependencies]`.
Cargo.lock	Removes `tokio-current-thread` and related transitive deps from the lockfile.

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Copilot · 2026-04-20T05:07:23Z

+        let rt = tokio::runtime::Builder::new_current_thread()
+            .enable_all()
+            .build()
+            .expect("tokio runtime");


tokio::runtime::Builder::new_current_thread()...build() is duplicated in both run and run_with_runtime. Consider extracting a small helper (e.g., fn new_test_runtime() -> Runtime) to keep the harness DRY and make future runtime configuration changes less error-prone.

Copilot · 2026-04-20T05:07:24Z

+        let rt = tokio::runtime::Builder::new_current_thread()
+            .enable_all()
+            .build()
+            .expect("tokio runtime");


The expect("tokio runtime") message is fairly generic; if runtime construction fails it will be hard to diagnose from test logs. Consider using a more specific message (e.g., indicate current-thread runtime build failure).

anikettuli · 2026-04-20T05:21:32Z

Superseded by #973 — the five dead-weight/MSRV modernizations are bundled there to avoid five near-identical Cargo.toml / Cargo.lock merges. Each change remains a distinct commit for piecewise review.

Copilot AI review requested due to automatic review settings April 20, 2026 05:03

Copilot started reviewing on behalf of anikettuli April 20, 2026 05:04 View session

Copilot AI reviewed Apr 20, 2026

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anikettuli mentioned this pull request Apr 20, 2026

chore: workspace modernization — MSRV 1.85, drop 4 unmaintained deps #973

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anikettuli closed this Apr 20, 2026

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test: replace tokio-current-thread alpha with tokio LocalSet#971

test: replace tokio-current-thread alpha with tokio LocalSet#971
anikettuli wants to merge 1 commit intoStremio:developmentfrom
anikettuli:claude/remove-tokio-current-thread

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anikettuli commented Apr 20, 2026

Summary

Why this change

Effect

Changes

src/unit_tests/env.rs

Cargo.toml

Cargo.lock

Public API / contract

Test plan

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stremio-core-web prebuild

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Pull request overview

Reviewed changes

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`src/unit_tests/env.rs`

`Cargo.toml`

`Cargo.lock`