Always use sys.exit when exiting the application

The `exit()` [1] function is not necessarily present in every Python
environment, as it's added by the `site` module. Also, this function is
"[...] useful for the interactive interpreter shell and should not be
used in programs"

For this reason, we replace all such occurrences with `sys.exit()` [2],
which is the canonical function to exit Python programs.

[1]: https://docs.python.org/3/library/constants.html#exit
[2]: https://docs.python.org/3/library/sys.html#sys.exit

dangerzone/args.py

@@ -1,5 +1,6 @@
 import functools
 import os
+import sys
 from typing import List, Optional, Tuple
 
 import click
@@ -86,7 +87,7 @@ def check_suspicious_options(args: List[str]) -> None:
             f" current working directory: {filenames_str}"
         )
         click.echo(msg)
-        exit(1)
+        sys.exit(1)
 
 
 def override_parser_and_check_suspicious_options(click_main: click.Command) -> None:

dangerzone/cli.py

@@ -67,7 +67,7 @@ def cli_main(
         dangerzone.add_document_from_filename(filenames[0], output_filename, archive)
     elif len(filenames) > 1 and output_filename:
         click.echo("--output-filename can only be used with one input file.")
-        exit(1)
+        sys.exit(1)
     else:
         for filename in filenames:
             dangerzone.add_document_from_filename(filename, archive=archive)
@@ -83,7 +83,7 @@ def cli_main(
             click.echo("Invalid OCR language code. Valid language codes:")
             for lang in dangerzone.ocr_languages:
                 click.echo(f"{dangerzone.ocr_languages[lang]}: {lang}")
-            exit(1)
+            sys.exit(1)
 
     # Ensure container is installed
     dangerzone.isolation_provider.install()

dangerzone/errors.py

@@ -107,6 +107,6 @@ def handle_document_errors(func: F) -> F:
                 msg = "An exception occured while validating a document"
                 log.exception(msg)
             click.echo(str(e))
-            exit(1)
+            sys.exit(1)
 
     return cast(F, wrapper)

dev_scripts/qa.py

@@ -430,7 +430,7 @@ class Reference:
                 " to date with the respective doc section, and then update the cached"
                 " section in this file."
             )
-            exit(1)
+            sys.exit(1)
 
     def find_section_text(self, md_text):
         """Find a section's content in a provided Markdown string."""
@@ -978,7 +978,7 @@ def parse_args():
 
     if not args.check_refs and not args.platform:
         parser.print_help(sys.stderr)
-        exit(1)
+        sys.exit(1)
 
     return args
 

install/macos/build-app.py

@@ -7,6 +7,7 @@ import itertools
 import os
 import shutil
 import subprocess
+import sys
 
 root = os.path.dirname(
     os.path.dirname(
@@ -69,7 +70,7 @@ def sign_app_bundle(build_path, dist_path, app_path):
     # Detect if create-dmg is installed
     if not os.path.exists(app_path):
         print(f"ERROR: Dangerzone.app not found in {app_path}.")
-        exit(1)
+        sys.exit(1)
 
     dmg_path = os.path.join(dist_path, "Dangerzone.dmg")
     icon_path = os.path.join(root, "install", "macos", "dangerzone.icns")

tests/test_large_set.py

@@ -1,6 +1,7 @@
 import os
 import re
 import subprocess
+import sys
 import time
 from pathlib import Path
 from typing import List
@@ -23,7 +24,7 @@ FORMATS_REGEX = (
 def ensure_test_data_exists() -> None:
     if len(os.listdir(test_docs_repo_dir)) == 0:
         print("Test data repository it empty. Skipping large tests.")
-        exit(1)
+        sys.exit(1)
 
 
 def get_test_docs(min_size: int, max_size: int) -> List[Path]: