Improved handling of deprecated single line variables for usage with …

…Visual Studio Code (issue #1363)

CHANGELOG.md

@@ -5,6 +5,7 @@ NOTE: isort follows the [semver](https://semver.org/) versioning standard.
 
 ### 5.3.0 TBD
   - Implemented ability to treat all or select comments as code (issue #1357)
+  - Improved handling of deprecated single line variables for usage with Visual Studio Code (issue #1363)
 
 ### 5.2.2 July 30, 2020
   - Fixed #1356: return status when arguments are passed in without files or a content stream.

isort/main.py

@@ -23,6 +23,35 @@
     pass
 
 shebang_re = re.compile(br"^#!.*\bpython[23w]?\b")
+DEPRECATED_SINGLE_DASH_ARGS = {
+    "-ac",
+    "-af",
+    "-ca",
+    "-cs",
+    "-df",
+    "-ds",
+    "-dt",
+    "-fas",
+    "-fass",
+    "-ff",
+    "-fgw",
+    "-fss",
+    "-lai",
+    "-lbt",
+    "-le",
+    "-ls",
+    "-nis",
+    "-nlb",
+    "-ot",
+    "-rr",
+    "-sd",
+    "-sg",
+    "-sl",
+    "-sp",
+    "-tc",
+    "-wl",
+    "-ws",
+}
 QUICK_GUIDE = f"""
 {ASCII_ART}
 
@@ -696,10 +725,24 @@ def _build_arg_parser() -> argparse.ArgumentParser:
         const="--keep-direct-and-as",
         help=argparse.SUPPRESS,
     )
+
     return parser
 
 
 def parse_args(argv: Optional[Sequence[str]] = None) -> Dict[str, Any]:
+    argv = sys.argv[1:] if argv is None else list(argv)
+    for index, arg in enumerate(argv):
+        if arg in DEPRECATED_SINGLE_DASH_ARGS:
+            warn(
+                f"\n\nThe following deprecated single dash CLI flags was used: {arg}!\n"
+                f"It is being auto translated to -{arg} to maintain backward compatibility.\n"
+                f"This behavior will be REMOVED in the 6.x.x release and is not guaranteed across"
+                f" 5.x.x releases.\n\n"
+                "Please see the 5.0.0 upgrade guide:\n"
+                "\thttps://timothycrosley.github.io/isort/docs/upgrade_guides/5.0.0/\n"
+            )
+            argv[index] = f"-{arg}"
+
     parser = _build_arg_parser()
     arguments = {key: value for key, value in vars(parser.parse_args(argv)).items() if value}
     if "dont_order_by_type" in arguments:

tests/test_main.py

@@ -90,7 +90,7 @@ def test_is_python_file_fifo(tmpdir):
 
 def test_main(capsys, tmpdir):
     base_args = [
-        "--settings-path",
+        "-sp",
         str(tmpdir),
         "--virtual-env",
         str(tmpdir),