style: add script for formatting python files

Signed-off-by: Niladri Halder <[email protected]>

scripts/python/fmt.sh

@@ -0,0 +1,122 @@
+#!/usr/bin/env bash
+
+SCRIPT_DIR="$(dirname "$(realpath "${BASH_SOURCE[0]:-"$0"}")")"
+ROOT_DIR="$SCRIPT_DIR/../.."
+
+# Imports
+source "$ROOT_DIR"/scripts/utils/log.sh
+
+set -e
+
+fmt() {
+  local -r paths_glob=$1
+
+  bash -c "
+  black --quiet $paths_glob &&
+  isort --profile=black --quiet $paths_glob &&
+  autoflake --quiet -r -i --remove-unused-variables --remove-all-unused-imports --expand-star-imports $paths_glob"
+}
+
+fmt_diff() {
+  local -r paths_glob=($(bash -c "echo $1"))
+
+  for path in "${paths_glob[@]}"; do
+    find "$path" -type f -name "*.py" -exec bash -c '
+      OUTPUT=$(diff -u --color=always <(cat {}) <(black -c "$(cat {})" |
+        isort --profile=black -d - |
+        autoflake --remove-unused-variables --remove-all-unused-imports --expand-star-imports -s -)
+      );
+      if [ -n "$OUTPUT" ]; then
+        echo -e "Diff for file {}\n===================================================\n$OUTPUT\n" | cat
+      fi
+      ' \;
+  done
+}
+
+fmt_check() {
+  local -r paths_glob=$1
+
+  local error=
+  bash -c "
+    black --quiet $paths_glob --check &&
+    isort --profile=black --quiet $paths_glob --check 2> /dev/null &&
+    autoflake --quiet -r --remove-unused-variables --remove-all-unused-imports --expand-star-imports $paths_glob --check > /dev/null
+    " || error=$?
+
+  if [ -n "$error" ]; then
+    exit $error
+  fi
+  exit 0
+}
+
+CHECK=
+DIFF=
+PATHS_GLOB=
+DEFAULT_PATHS_GLOB=$(realpath "$ROOT_DIR"/tests/bdd)/{common,features}
+
+# Print usage options for this script.
+print_help() {
+  cat <<EOF
+Usage: $(basename "${0}") [OPTIONS]
+
+Options:
+  -h, --help              Display this text.
+  --check                 Don't write the files back, just return the status.
+                          Return code 0 means nothing would change. Return code
+                          1 means some files would be changed.
+  --diff                  Don't write the files back, just output a diff to
+                          indicate what changes would've been made.
+  --paths-glob <glob>     Input a paths glob of directories and/or files which
+                          would be parsed recursively. (default: "$DEFAULT_PATHS_GLOB")
+
+Examples:
+  $(basename "${0}") --check
+EOF
+}
+
+# Parse args.
+while test $# -gt 0; do
+  arg="$1"
+  case "$arg" in
+  --check)
+    CHECK=1
+    ;;
+  --diff)
+    DIFF=1
+    ;;
+  --paths-glob*)
+    if [ "$arg" = "--paths-glob" ]; then
+      test $# -lt 2 && log_fatal "Missing value for the optional argument '$arg'."
+      PATHS_GLOB="$2"
+      shift
+    else
+      PATHS_GLOB="${arg#*=}"
+    fi
+    ;;
+  -h* | --help*)
+    print_help
+    exit 0
+    ;;
+  *)
+    print_help
+    log_fatal "unexpected argument '$arg'" 1
+    ;;
+  esac
+  shift
+done
+
+if [ -z "$PATHS_GLOB" ]; then
+  PATHS_GLOB=$DEFAULT_PATHS_GLOB
+fi
+
+if [ -n "$CHECK" ]; then
+  fmt_check "$PATHS_GLOB"
+fi
+
+if [ -n "$DIFF" ]; then
+  fmt_diff "$PATHS_GLOB"
+fi
+
+if [[ -z "$CHECK" ]] && [[ -z "$DIFF" ]]; then
+  fmt "$PATHS_GLOB"
+fi