1 files changed, 31 insertions, 0 deletions
diff --git a/src/doc/rustc-dev-guide/ci/linkcheck.sh b/src/doc/rustc-dev-guide/ci/linkcheck.sh
new file mode 100755
index 000000000..5d49d1337
--- /dev/null
+++ b/src/doc/rustc-dev-guide/ci/linkcheck.sh
@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+
+set -e
+set -o pipefail
+
+# https://docs.github.com/en/actions/reference/environment-variables
+if [ "$GITHUB_EVENT_NAME" = "schedule" ] ; then # running in scheduled job
+  FLAGS=""
+
+  echo "Doing full link check."
+  set -x
+elif [ "$GITHUB_EVENT_NAME" = "pull_request" ] ; then # running in PR CI build
+  if [ -z "$BASE_SHA" ]; then
+    echo "error: unexpected state: BASE_SHA must be non-empty in CI"
+    exit 1
+  fi
+
+  CHANGED_FILES=$(git diff --name-only $BASE_SHA... | tr '\n' ' ')
+  FLAGS="--no-cache -f $CHANGED_FILES"
+
+  echo "Checking files changed since $BASE_SHA: $CHANGED_FILES"
+  set -x
+else # running locally
+  COMMIT_RANGE=master...
+  CHANGED_FILES=$(git diff --name-only $COMMIT_RANGE | tr '\n' ' ')
+  FLAGS="-f $CHANGED_FILES"
+
+  echo "Checking files changed in $COMMIT_RANGE: $CHANGED_FILES"
+fi
+
+exec mdbook-linkcheck $FLAGS