Add tests/syntax_check.sh

tests/syntax_check.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+#
+# Validate Bash syntax for all shell scripts in this repository.
+#
+# Usage:
+#   bash tests/syntax_check.sh
+
+set -Eeuo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+status=0
+
+while IFS= read -r -d '' script; do
+  printf 'Checking %s\n' "${script#"$ROOT_DIR/"}"
+  if ! bash -n "$script"; then
+    status=1
+  fi
+done < <(find "$ROOT_DIR" -type f -name '*.sh' -print0 | sort -z)
+
+if [[ "$status" -eq 0 ]]; then
+  printf 'All Bash files passed syntax validation.\n'
+fi
+
+exit "$status"
+