script/test: ignore python checks if not available (#6530)

scripts/test.sh

@@ -9,6 +9,40 @@
 # NOTE: must be run from the repository root directory to correctly work!
 # NOTE: `set -e` is applied conditionally only if needed.
 
+# check if a command is available to run in the system
+function exists {
+  command -v "$1" >/dev/null 2>&1
+}
+
+# Wrapper around black as it outputs everything to stderr,
+# but we want to only print if there are actual errors, and not
+# the "All done!" success message.
+function run_black {
+  # skip black check if command is not available in the system.
+  if [ "$CI" != "true" ] && ! exists black; then
+    echo "Skipping black check, command not available."
+    return 0
+  fi
+
+  # we want to ignore the exit code from black on failure, so that we can
+  # do the conditional printing below
+  errs=$(black scripts --check 2>&1 || true)
+  if [[ ${errs} != "All done!"* ]]; then
+     echo -e "${errs}" >&2
+     return 1
+  fi
+}
+
+function run_flake8 {
+  # skip flake8 check if command is not available in the system.
+  if [ "$CI" != "true" ] && ! exists flake8; then
+    echo "Skipping flake8 check, command not available."
+    return 0
+  fi
+
+  flake8 scripts
+}
+
 # Default test function, ran by `npm test`.
 function run_tests {
   markdownlint pages*/**/*.md
@@ -17,20 +51,7 @@ function run_tests {
     tldr-lint --ignore "TLDR003,TLDR004,TLDR005,TLDR015,TLDR104" ${f}
   done
   run_black
-  flake8 scripts
-}
-
-# Wrapper around black as it outputs everything to stderr,
-# but we want to only print if there are actual errors, and not
-# the "All done!" success message.
-function run_black {
-  # we want to ignore the exit code from black on failure, so that we can
-  # do the conditional printing below
-  errs=$(black scripts --check 2>&1 || true)
-  if [[ ${errs} != "All done!"* ]]; then
-     echo -e "${errs}" >&2
-     return 1
-  fi
+  run_flake8
 }
 
 # Special test function for GitHub Actions pull request builds.