Re-add install-rust action

This re-adds install-rust action removed in a91c37d.

rustup sometimes fails due to temporary network problems even when
RUSTUP_MAX_RETRIES is set, so an action with retry is needed.

.github/workflows/ci.yml

@@ -75,6 +75,24 @@ jobs:
           ls -- /Applications | grep -F Xcode
         if: startsWith(matrix.os, 'macos')
 
+  install-rust:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: taiki-e/checkout-action@v1
+      - uses: ./install-rust
+        with:
+          toolchain: nightly
+          component: rustfmt,clippy
+          target: x86_64-unknown-linux-musl,i686-unknown-linux-gnu
+      - run: |
+          rustc -Vv
+          rustup -V
+          cargo -Vv
+          rustfmt -V
+          cargo clippy -V
+          rustup component list
+          rustup target list
+
   setup-docker:
     runs-on: ubuntu-latest
     steps:

README.md

@@ -9,6 +9,7 @@ supposed to only be used in infra managed by us.
 ## Actions
 
 - [**free-device-space**](free-device-space): Free device space.
+- [**install-rust**](install-rust): Install Rust toolchain.
 - [**setup-docker**](setup-docker): Setup docker.
 
 ## Reusable workflows
@@ -38,7 +39,6 @@ These actions were previously included in this repository but have been moved in
 These actions were previously included in this repository but have been removed.
 
 - **deploy-gh-pages**: removed because no longer used.
-- **install-rust**: removed in favor of calling `rustup` directly.
 - **update-dependabot-pr**: removed because no longer used.
 
 [checkout-action]: https://github.com/taiki-e/checkout-action

install-rust/README.md

@@ -0,0 +1,20 @@
+# install-rust
+
+GitHub Action for installing Rust toolchain.
+There is no stability guarantee for this action, since it's supposed to only be
+used in infra managed by us.
+
+## Usage
+
+See [action.yml](action.yml)
+
+```yaml
+- uses: taiki-e/github-actions/install-rust@main
+  with:
+    # Default toolchain to install.
+    toolchain: stable
+    # Components to add (comma-separated), default is empty.
+    component: rustfmt,clippy
+    # Targets to add (comma-separated), default is empty.
+    target: x86_64-unknown-linux-musl
+```

install-rust/action.yml

@@ -0,0 +1,27 @@
+name: install-rust
+description: GitHub Action for installing Rust toolchain
+
+inputs:
+  toolchain:
+    description: Default toolchain to install
+    required: true
+    # default: #publish:toolchain
+  component:
+    description: Components to add (comma-separated)
+    required: false
+  target:
+    description: Targets to add (comma-separated)
+    required: false
+
+# Note:
+# - inputs.* should be manually mapped to INPUT_* due to https://github.com/actions/runner/issues/665
+# - Use GITHUB_*/RUNNER_* instead of github.*/runner.* due to https://github.com/actions/runner/issues/2185
+runs:
+  using: composite
+  steps:
+    - run: bash --noprofile --norc "${GITHUB_ACTION_PATH:?}/main.sh"
+      shell: bash
+      env:
+        INPUT_TOOLCHAIN: ${{ inputs.toolchain }}
+        INPUT_COMPONENT: ${{ inputs.component }}
+        INPUT_TARGET: ${{ inputs.target }}

install-rust/main.sh

@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+set -CeEuo pipefail
+IFS=$'\n\t'
+trap -- 's=$?; printf >&2 "%s\n" "${0##*/}:${LINENO}: \`${BASH_COMMAND}\` exit with ${s}"; exit ${s}' ERR
+
+g() {
+    IFS=' '
+    local cmd="$*"
+    IFS=$'\n\t'
+    printf '::group::%s\n' "${cmd#retry }"
+    "$@"
+    printf '::endgroup::\n'
+}
+retry() {
+    for i in {1..10}; do
+        if "$@"; then
+            return 0
+        else
+            sleep "${i}"
+        fi
+    done
+    "$@"
+}
+
+export RUSTUP_MAX_RETRIES="${RUSTUP_MAX_RETRIES:-10}"
+
+# --no-self-update is necessary because the windows environment cannot self-update rustup.exe.
+rustup_args=(--no-self-update --profile minimal)
+toolchain="${INPUT_TOOLCHAIN:?}"
+if [[ -n "${INPUT_COMPONENT:-}" ]]; then
+    rustup_args+=("--component=${INPUT_COMPONENT}")
+fi
+if [[ -n "${INPUT_TARGET:-}" ]]; then
+    rustup_args+=("--target=${INPUT_TARGET}")
+fi
+
+g retry rustup toolchain add "${toolchain}" "${rustup_args[@]}"
+
+g rustup default "${toolchain}"

install-rust/update-branch.sh

@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+set -CeEuo pipefail
+IFS=$'\n\t'
+trap -- 's=$?; printf >&2 "%s\n" "${0##*/}:${LINENO}: \`${BASH_COMMAND}\` exit with ${s}"; exit ${s}' ERR
+cd -- "$(dirname -- "$0")"/..
+
+# Update stable/beta/nightly branches.
+#
+# USAGE:
+#    ./install-rust/update-branch.sh
+
+retry() {
+    for i in {1..10}; do
+        if "$@"; then
+            return 0
+        else
+            sleep "${i}"
+        fi
+    done
+    "$@"
+}
+bail() {
+    printf >&2 'error: %s\n' "$*"
+    exit 1
+}
+
+if [[ $# -gt 1 ]]; then
+    bail "invalid argument '$2'"
+fi
+if { sed --help 2>&1 || true; } | grep -Eq -e '-i extension'; then
+    in_place=(-i '')
+else
+    in_place=(-i)
+fi
+
+# Make sure there is no uncommitted change.
+git diff --exit-code
+git diff --exit-code --staged
+
+# Make sure that the release was created from an allowed branch.
+if ! git branch | grep -Eq '\* main$'; then
+    bail "current branch is not 'main'"
+fi
+if ! git remote -v | grep -F origin | grep -Eq 'github\.com[:/]taiki-e/'; then
+    bail "cannot publish a new release from fork repository"
+fi
+
+set -x
+
+retry git push origin main
+
+toolchains=(
+    stable
+    beta
+    nightly
+)
+
+for toolchain in "${toolchains[@]}"; do
+    git checkout -b "${toolchain}"
+    sed -E "${in_place[@]}" "s/required: true/required: false/g" install-rust/action.yml
+    sed -E "${in_place[@]}" "s/# default: #publish:toolchain/default: ${toolchain}/g" install-rust/action.yml
+    git add install-rust/action.yml
+    git commit -m "${toolchain}"
+    retry git push origin -f refs/heads/"${toolchain}"
+    git checkout main
+    git branch -D "${toolchain}"
+done