Lint shell scripts in CI

ci/buildkite.yml

@@ -29,6 +29,8 @@ steps:
         user: "998:997" # buildkite-agent:buildkite-agent
   - command: "ci/test-cuda.sh"
     label: "cuda"
+  - command: "ci/shellcheck.sh"
+    label: "shellcheck [public]"
   - wait
   - command: "ci/publish.sh"
     label: "publish release artifacts"

ci/shellcheck.sh

@@ -0,0 +1,14 @@
+#!/bin/bash -e
+#
+# Reference: https://github.com/koalaman/shellcheck/wiki/Directive
+
+cd "$(dirname "$0")/.."
+
+set -x
+docker pull koalaman/shellcheck
+find . -name "*.sh" -not -regex ".*/.cargo/.*" -print0 \
+  | xargs -0 \
+      docker run -w /work -v "$PWD:/work" \
+        koalaman/shellcheck --color=always --external-sources --shell=bash
+
+exit 0