0.3 backports

.github/workflows/ci.yml

@@ -1,5 +1,8 @@
 name: CI
 
+permissions:
+  contents: read
+
 on:
   pull_request:
   push:
@@ -10,8 +13,12 @@ on:
     - cron: '0 1 * * *'
 
 env:
-  RUSTFLAGS: -D warnings
+  CARGO_INCREMENTAL: 0
+  CARGO_NET_RETRY: 10
+  CARGO_TERM_COLOR: always
   RUST_BACKTRACE: 1
+  RUSTFLAGS: -D warnings
+  RUSTUP_MAX_RETRIES: 10
 
 defaults:
   run:
@@ -49,18 +56,19 @@ jobs:
       - uses: actions/checkout@v2
       - name: Install Rust
         run: rustup update nightly && rustup default nightly
-      - run: cargo install cross
+      - name: Install cross
+        uses: taiki-e/install-action@cross
       - run: cross test --target ${{ matrix.target }} --workspace --all-features
       - run: cross test --target ${{ matrix.target }} --workspace --all-features --release
         # TODO: https://github.com/rust-lang/futures-rs/issues/2451
         if: matrix.target != 'aarch64-unknown-linux-gnu'
 
   core-msrv:
-    name: cargo +${{ matrix.rust }} build (futures-{core, io, sink, task})
+    name: cargo +${{ matrix.rust }} build (futures-{core, io, sink})
     strategy:
       matrix:
         rust:
-          # This is the minimum Rust version supported by futures-core, futures-io, futures-sink, futures-task.
+          # This is the minimum Rust version supported by futures-core, futures-io, futures-sink.
           # When updating this, the reminder to update the minimum required version in README.md, Cargo.toml, and .clippy.toml.
           - 1.36
     runs-on: ubuntu-latest
@@ -70,36 +78,38 @@ jobs:
         run: rustup update ${{ matrix.rust }} && rustup default ${{ matrix.rust }}
       # cargo does not support for --features/--no-default-features with workspace, so use cargo-hack instead.
       # Refs: cargo#3620, cargo#4106, cargo#4463, cargo#4753, cargo#5015, cargo#5364, cargo#6195
-      - run: cargo +stable install cargo-hack
+      - name: Install cargo-hack
+        uses: taiki-e/install-action@cargo-hack
       # remove dev-dependencies to avoid https://github.com/rust-lang/cargo/issues/4866
       - run: cargo hack --remove-dev-deps --workspace
       # Check no-default-features
       - run: |
           cargo hack build --workspace --ignore-private --no-default-features \
-            --exclude futures --exclude futures-util --exclude futures-macro --exclude futures-executor --exclude futures-channel --exclude futures-test
+            --exclude futures --exclude futures-util --exclude futures-task --exclude futures-macro --exclude futures-executor --exclude futures-channel --exclude futures-test
       # Check alloc feature
       - run: |
           cargo hack build --workspace --ignore-private --no-default-features --features alloc --ignore-unknown-features \
-            --exclude futures --exclude futures-util --exclude futures-macro --exclude futures-executor --exclude futures-channel --exclude futures-test
+            --exclude futures --exclude futures-util --exclude futures-task --exclude futures-macro --exclude futures-executor --exclude futures-channel --exclude futures-test
       # Check std feature
       - run: |
           cargo hack build --workspace --ignore-private --no-default-features --features std \
-            --exclude futures --exclude futures-util --exclude futures-macro --exclude futures-executor --exclude futures-channel --exclude futures-test
+            --exclude futures --exclude futures-util --exclude futures-task --exclude futures-macro --exclude futures-executor --exclude futures-channel --exclude futures-test
 
   util-msrv:
     name: cargo +${{ matrix.rust }} build
     strategy:
       matrix:
         rust:
-          # This is the minimum Rust version supported by futures, futures-util, futures-macro, futures-executor, futures-channel, futures-test.
+          # This is the minimum Rust version supported by futures, futures-util, futures-task, futures-macro, futures-executor, futures-channel, futures-test.
           # When updating this, the reminder to update the minimum required version in README.md and Cargo.toml.
           - 1.45
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
       - name: Install Rust
         run: rustup update ${{ matrix.rust }} && rustup default ${{ matrix.rust }}
-      - run: cargo +stable install cargo-hack
+      - name: Install cargo-hack
+        uses: taiki-e/install-action@cargo-hack
       # remove dev-dependencies to avoid https://github.com/rust-lang/cargo/issues/4866
       - run: cargo hack --remove-dev-deps --workspace
       # Check default features
@@ -129,7 +139,8 @@ jobs:
       - uses: actions/checkout@v2
       - name: Install Rust
         run: rustup update ${{ matrix.rust }} && rustup default ${{ matrix.rust }}
-      - run: cargo install cargo-hack
+      - name: Install cargo-hack
+        uses: taiki-e/install-action@cargo-hack
       - run: cargo hack build --workspace --no-dev-deps
       - run: cargo build --tests --features default,thread-pool,io-compat --manifest-path futures/Cargo.toml
 
@@ -140,7 +151,8 @@ jobs:
       - uses: actions/checkout@v2
       - name: Install Rust
         run: rustup update nightly && rustup default nightly
-      - run: cargo install cargo-hack
+      - name: Install cargo-hack
+        uses: taiki-e/install-action@cargo-hack
       # remove dev-dependencies to avoid https://github.com/rust-lang/cargo/issues/4866
       - run: cargo hack --remove-dev-deps --workspace
       - run: cargo update -Z minimal-versions
@@ -162,7 +174,8 @@ jobs:
       - name: Install Rust
         run: rustup update nightly && rustup default nightly
       - run: rustup target add ${{ matrix.target }}
-      - run: cargo install cargo-hack
+      - name: Install cargo-hack
+        uses: taiki-e/install-action@cargo-hack
       # remove dev-dependencies to avoid https://github.com/rust-lang/cargo/issues/4866
       - run: cargo hack --remove-dev-deps --workspace
       - run: |
@@ -202,7 +215,8 @@ jobs:
       - uses: actions/checkout@v2
       - name: Install Rust
         run: rustup update nightly && rustup default nightly
-      - run: cargo install cargo-hack
+      - name: Install cargo-hack
+        uses: taiki-e/install-action@cargo-hack
       # Check each specified feature works properly
       # * `--feature-powerset` - run for the feature powerset of the package
       # * `--depth 2` - limit the max number of simultaneous feature flags of `--feature-powerset`
@@ -217,17 +231,52 @@ jobs:
             --features unstable --ignore-unknown-features
 
   # When this job failed, run ci/no_atomic_cas.sh and commit result changes.
-  # TODO(taiki-e): Ideally, this should be automated using a bot that creates
-  #                PR when failed, but there is no bandwidth to implement it
-  #                right now...
   codegen:
     runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
     steps:
       - uses: actions/checkout@v2
       - name: Install Rust
         run: rustup update nightly && rustup default nightly
       - run: ci/no_atomic_cas.sh
-      - run: git diff --exit-code
+      - run: git add -N . && git diff --exit-code
+        if: github.repository_owner != 'rust-lang' || github.event_name != 'schedule'
+      - id: diff
+        run: |
+          git config user.name "Taiki Endo"
+          git config user.email "te316e89@gmail.com"
+          git add -N .
+          if ! git diff --exit-code; then
+              git add .
+              git commit -m "Update no_atomic_cas.rs"
+              echo "::set-output name=success::false"
+          fi
+        if: github.repository_owner == 'rust-lang' && github.event_name == 'schedule'
+      - uses: peter-evans/create-pull-request@v3
+        with:
+          title: Update no_atomic_cas.rs
+          body: |
+            Auto-generated by [create-pull-request][1]
+            [Please close and immediately reopen this pull request to run CI.][2]
+
+            [1]: https://github.com/peter-evans/create-pull-request
+            [2]: https://github.com/peter-evans/create-pull-request/blob/HEAD/docs/concepts-guidelines.md#workarounds-to-trigger-further-workflow-runs
+          branch: update-no-atomic-cas-rs
+        if: github.repository_owner == 'rust-lang' && github.event_name == 'schedule' && steps.diff.outputs.success == 'false'
+
+  miri:
+    name: cargo miri test
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install Rust
+        run: rustup toolchain install nightly --component miri && rustup default nightly
+      # futures-executor uses boxed futures so many tests trigger https://github.com/rust-lang/miri/issues/1038
+      - run: cargo miri test --workspace --exclude futures-executor --all-features
+        env:
+          MIRIFLAGS: -Zmiri-check-number-validity -Zmiri-symbolic-alignment-check -Zmiri-tag-raw-pointers -Zmiri-disable-isolation
 
   san:
     name: cargo test -Z sanitizer=${{ matrix.sanitizer }}
@@ -263,6 +312,7 @@ jobs:
   #     - run: cargo clippy --workspace --all-features --all-targets
 
   fmt:
+    name: cargo fmt
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2

ci/no_atomic_cas.sh

@@ -1,28 +1,31 @@
 #!/bin/bash
+set -euo pipefail
+IFS=$'\n\t'
+cd "$(dirname "$0")"/..
 
 # Update the list of targets that do not support atomic CAS operations.
 #
 # Usage:
 #    ./ci/no_atomic_cas.sh
 
-set -euo pipefail
-IFS=$'\n\t'
-
-cd "$(cd "$(dirname "$0")" && pwd)"/..
-
 file="no_atomic_cas.rs"
 
-{
-    echo "// This file is @generated by $(basename "$0")."
-    echo "// It is not intended for manual editing."
-    echo ""
-    echo "const NO_ATOMIC_CAS_TARGETS: &[&str] = &["
-} >"$file"
-
+no_atomic_cas=()
 for target in $(rustc --print target-list); do
-    res=$(rustc --print target-spec-json -Z unstable-options --target "$target" \
-        | jq -r "select(.\"atomic-cas\" == false)")
-    [[ -z "$res" ]] || echo "    \"$target\"," >>"$file"
+    target_spec=$(rustc --print target-spec-json -Z unstable-options --target "${target}")
+    res=$(jq <<<"${target_spec}" -r 'select(."atomic-cas" == false)')
+    [[ -z "${res}" ]] || no_atomic_cas+=("${target}")
 done
 
-echo "];" >>"$file"
+cat >"${file}" <<EOF
+// This file is @generated by $(basename "$0").
+// It is not intended for manual editing.
+
+const NO_ATOMIC_CAS: &[&str] = &[
+EOF
+for target in "${no_atomic_cas[@]}"; do
+    echo "    \"${target}\"," >>"${file}"
+done
+cat >>"${file}" <<EOF
+];
+EOF

futures-channel/build.rs

@@ -1,9 +1,3 @@
-#![warn(rust_2018_idioms, single_use_lifetimes)]
-
-use std::env;
-
-include!("no_atomic_cas.rs");
-
 // The rustc-cfg listed below are considered public API, but it is *unstable*
 // and outside of the normal semver guarantees:
 //
@@ -13,10 +7,15 @@ include!("no_atomic_cas.rs");
 //      need to enable it manually when building for custom targets or using
 //      non-cargo build systems that don't run the build script.
 //
-// With the exceptions mentioned above, the rustc-cfg strings below are
-// *not* public API. Please let us know by opening a GitHub issue if your build
-// environment requires some way to enable these cfgs other than by executing
-// our build script.
+// With the exceptions mentioned above, the rustc-cfg emitted by the build
+// script are *not* public API.
+
+#![warn(rust_2018_idioms, single_use_lifetimes)]
+
+use std::env;
+
+include!("no_atomic_cas.rs");
+
 fn main() {
     let target = match env::var("TARGET") {
         Ok(target) => target,
@@ -34,7 +33,7 @@ fn main() {
     // `cfg(target_has_atomic = "ptr")` as true when the build script doesn't
     // run. This is needed for compatibility with non-cargo build systems that
     // don't run the build script.
-    if NO_ATOMIC_CAS_TARGETS.contains(&&*target) {
+    if NO_ATOMIC_CAS.contains(&&*target) {
         println!("cargo:rustc-cfg=futures_no_atomic_cas");
     }
 

futures-channel/tests/mpsc-close.rs

@@ -147,6 +147,7 @@ fn single_receiver_drop_closes_channel_and_drains() {
 
 // Stress test that `try_send()`s occurring concurrently with receiver
 // close/drops don't appear as successful sends.
+#[cfg_attr(miri, ignore)] // Miri is too slow
 #[test]
 fn stress_try_send_as_receiver_closes() {
     const AMT: usize = 10000;

futures-channel/tests/mpsc.rs

@@ -200,6 +200,9 @@ fn tx_close_gets_none() {
 
 #[test]
 fn stress_shared_unbounded() {
+    #[cfg(miri)]
+    const AMT: u32 = 100;
+    #[cfg(not(miri))]
     const AMT: u32 = 10000;
     const NTHREADS: u32 = 8;
     let (tx, rx) = mpsc::unbounded::<i32>();
@@ -229,6 +232,9 @@ fn stress_shared_unbounded() {
 
 #[test]
 fn stress_shared_bounded_hard() {
+    #[cfg(miri)]
+    const AMT: u32 = 100;
+    #[cfg(not(miri))]
     const AMT: u32 = 10000;
     const NTHREADS: u32 = 8;
     let (tx, rx) = mpsc::channel::<i32>(0);
@@ -259,6 +265,9 @@ fn stress_shared_bounded_hard() {
 #[allow(clippy::same_item_push)]
 #[test]
 fn stress_receiver_multi_task_bounded_hard() {
+    #[cfg(miri)]
+    const AMT: usize = 100;
+    #[cfg(not(miri))]
     const AMT: usize = 10_000;
     const NTHREADS: u32 = 2;
 
@@ -327,6 +336,11 @@ fn stress_receiver_multi_task_bounded_hard() {
 /// after sender dropped.
 #[test]
 fn stress_drop_sender() {
+    #[cfg(miri)]
+    const ITER: usize = 100;
+    #[cfg(not(miri))]
+    const ITER: usize = 10000;
+
     fn list() -> impl Stream<Item = i32> {
         let (tx, rx) = mpsc::channel(1);
         thread::spawn(move || {
@@ -335,7 +349,7 @@ fn stress_drop_sender() {
         rx
     }
 
-    for _ in 0..10000 {
+    for _ in 0..ITER {
         let v: Vec<_> = block_on(list().collect());
         assert_eq!(v, vec![1, 2, 3]);
     }
@@ -380,9 +394,12 @@ fn stress_close_receiver_iter() {
     }
 }
 
+#[cfg_attr(miri, ignore)] // Miri is too slow
 #[test]
 fn stress_close_receiver() {
-    for _ in 0..10000 {
+    const ITER: usize = 10000;
+
+    for _ in 0..ITER {
         stress_close_receiver_iter();
     }
 }
@@ -397,6 +414,9 @@ async fn stress_poll_ready_sender(mut sender: mpsc::Sender<u32>, count: u32) {
 #[allow(clippy::same_item_push)]
 #[test]
 fn stress_poll_ready() {
+    #[cfg(miri)]
+    const AMT: u32 = 100;
+    #[cfg(not(miri))]
     const AMT: u32 = 1000;
     const NTHREADS: u32 = 8;
 
@@ -424,6 +444,7 @@ fn stress_poll_ready() {
     stress(16);
 }
 
+#[cfg_attr(miri, ignore)] // Miri is too slow
 #[test]
 fn try_send_1() {
     const N: usize = 3000;