avoid second iteration on urls

src/test/shell/bazel/verify_workspace.sh

@@ -46,25 +46,22 @@ function test_verify_urls() {
   # Find url-shaped lines, skipping jekyll-tree (which isn't a valid URL), and
   # skipping comments.
   invalid_urls=()
-  urls=()
+  checked_urls=()
   for file in "${WORKSPACE_FILES[@]}"; do
     for url in $(grep -E '"https://|http://' "${file}" | \
       sed -e '/jekyll-tree/d' -e '/^#/d' -r -e  's#^.*"(https?://[^"]+)".*$#\1#g' | \
       sort -u); do
       # add only unique url to the array
-      if [[ ${#urls[@]} == 0 ]] || [[ ! " ${urls[@]} " =~ " ${url} " ]]; then
-        urls+=("${url}")
+      if [[ ${#checked_urls[@]} == 0 ]] || [[ ! " ${checked_urls[@]} " =~ " ${url} " ]]; then
+        checked_urls+=("${url}")
+        echo "Checking ${url} ..."
+        if ! curl --head --silent --show-error --fail --output /dev/null --retry 3 "${url}"; then
+          invalid_urls+=("${url}")
+        fi
       fi
     done
   done
 
-  for url in "${urls[@]}"; do
-    echo "Checking ${url} ..."
-    if ! curl --head --silent --show-error --fail --output /dev/null --retry 3 "${url}"; then
-      invalid_urls+=("${url}")
-    fi
-  done
-
   if [[ ${#invalid_urls[@]} > 0 ]]; then
     fail "Invalid urls: ${invalid_urls[@]}"
   fi