Switch from Travis to GHA

.env

@@ -0,0 +1,4 @@
+MDBOOK_VERSION=0.4.7
+MDBOOK_LINKCHECK_VERSION=0.7.2
+MDBOOK_TOC_VERSION=0.6.1
+DEPLOY_DIR=book/html

.github/workflows/ci.yml

@@ -0,0 +1,86 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+  schedule:
+    # Run at 18:00 UTC every day
+    - cron: '0 18 * * *'
+
+jobs:
+  ci:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          # Set 0 to rebase later.
+          fetch-depth: 0
+
+      - name: Read .env
+        run: |
+          . ./.env
+          echo "MDBOOK_VERSION=${MDBOOK_VERSION}" >> $GITHUB_ENV
+          echo "MDBOOK_LINKCHECK_VERSION=${MDBOOK_LINKCHECK_VERSION}" >> $GITHUB_ENV
+          echo "MDBOOK_TOC_VERSION=${MDBOOK_TOC_VERSION}" >> $GITHUB_ENV
+          echo "DEPLOY_DIR=${DEPLOY_DIR}" >> $GITHUB_ENV
+
+      - name: Cache binaries
+        id: mdbook-cache
+        uses: actions/cache@v2
+        with:
+          path: |
+            ~/.cargo/bin
+          key: ${{ runner.os }}-${{ env.MDBOOK_VERSION }}--${{ env.MDBOOK_LINKCHECK_VERSION }}--${{ env.MDBOOK_TOC_VERSION }}
+
+      - name: Cache linkcheck
+        uses: actions/cache@v2
+        with:
+          path: |
+            ~/book/linkcheck
+          key: ${{ runner.os }}-${{ hashFiles('./book/linkcheck') }}
+
+      - name: Check line lengths
+        if: github.event_name != 'schedule'
+        run: |
+          shopt -s globstar
+          MAX_LINE_LENGTH=100 bash ci/check_line_lengths.sh src/**/*.md
+
+      - name: Install latest nightly Rust toolchain
+        if: steps.mdbook-cache.outputs.cache-hit != 'true'
+        uses: actions-rs/toolchain@v1
+        with:
+            toolchain: nightly
+            override: true
+
+      - name: Install Dependencies
+        if: steps.mdbook-cache.outputs.cache-hit != 'true'
+        run: |
+          cargo install mdbook --version ${{ env.MDBOOK_VERSION }}
+          cargo install mdbook-linkcheck --version ${{ env.MDBOOK_LINKCHECK_VERSION }}
+          cargo install mdbook-toc --version ${{ env.MDBOOK_TOC_VERSION }}
+
+      - name: Check build
+        if: github.event_name != 'schedule'
+        run: |
+          git switch -c ci
+          git fetch origin master
+          git rebase origin/master
+          git log --oneline | head -n 10
+          mdbook build
+
+      - name: Deploy to gh-pages
+        if: github.event_name == 'schedule' && github.repository == 'rust-lang/rustc-dev-guide'
+        run: |
+          mdbook build
+          touch "${{ env.DEPLOY_DIR }}/.nojekyll"
+          cp CNAME "${{ env.DEPLOY_DIR }}"
+          cd "${{ env.DEPLOY_DIR }}"
+          rm -rf .git
+          git init
+          git config user.name "Deploy from CI"
+          git config user.email ""
+          git add .
+          git commit -m "Deploy ${GITHUB_SHA} to gh-pages"
+          git push --quiet -f "https://x-token:${{ secrets.GITHUB_TOKEN }}@github.com/${GITHUB_REPOSITORY}" HEAD:gh-pages

ci/linkcheck.sh

@@ -3,22 +3,18 @@
 set -e
 set -o pipefail
 
-# https://docs.travis-ci.com/user/environment-variables/#default-environment-variables
-if [ "$TRAVIS_EVENT_TYPE" = "cron" ] ; then # running in cron job
+# https://docs.github.com/en/actions/reference/environment-variables
+if [ "$GITHUB_EVENT_NAME" = "schedule" ] ; then # running in scheduled job
   FLAGS=""
 
   echo "Doing full link check."
   set -x
 elif [ "$CI" = "true" ] ; then # running in PR CI build
-  if [ -z "$TRAVIS_COMMIT_RANGE" ]; then
-    echo "error: unexpected state: TRAVIS_COMMIT_RANGE must be non-empty in CI"
-    exit 1
-  fi
 
-  CHANGED_FILES=$(git diff --name-only $TRAVIS_COMMIT_RANGE | tr '\n' ' ')
+  CHANGED_FILES=$(git diff --name-only origin/master... | tr '\n' ' ')
   FLAGS="--no-cache -f $CHANGED_FILES"
 
-  echo "Checking files changed in $TRAVIS_COMMIT_RANGE: $CHANGED_FILES"
+  echo "Checking files changed in origin/master...: $CHANGED_FILES"
   set -x
 else # running locally
   COMMIT_RANGE=master...