🐛 Ensure an optional argument is shown in brackets, even when metavar is set (#1409)

Author: svlandeg

docs/tutorial/arguments/help.md

@@ -178,10 +178,10 @@ Now the generated help text will have `✨username✨` instead of `NAME`:
 ```console
 $ python main.py --help
 
-Usage: main.py [OPTIONS] ✨username✨
+Usage: main.py [OPTIONS] [✨username✨]
 
 Arguments:
-  ✨username✨  [default: World]
+  [✨username✨]  [default: World]
 
 Options:
   --help                Show this message and exit.

tests/test_tutorial/test_arguments/test_help/test_tutorial005.py

@@ -12,7 +12,7 @@
 def test_help():
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
-    assert "[OPTIONS] [NAME]" in result.output
+    assert "Usage: main [OPTIONS] [NAME]" in result.output
     assert "Arguments" in result.output
     assert "Who to greet" in result.output
     assert "[default: (Deadpoolio the amazing's name)]" in result.output

tests/test_tutorial/test_arguments/test_help/test_tutorial005_an.py

@@ -12,7 +12,7 @@
 def test_help():
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
-    assert "[OPTIONS] [NAME]" in result.output
+    assert "Usage: main [OPTIONS] [NAME]" in result.output
     assert "Arguments" in result.output
     assert "Who to greet" in result.output
     assert "[default: (Deadpoolio the amazing's name)]" in result.output

tests/test_tutorial/test_arguments/test_help/test_tutorial006.py

@@ -12,9 +12,8 @@
 def test_help():
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
-    assert "[OPTIONS] ✨username✨" in result.output
+    assert "Usage: main [OPTIONS] [✨username✨]" in result.output
     assert "Arguments" in result.output
-    assert "✨username✨" in result.output
     assert "[default: World]" in result.output
 
 

tests/test_tutorial/test_arguments/test_help/test_tutorial006_an.py

@@ -12,9 +12,8 @@
 def test_help():
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
-    assert "[OPTIONS] ✨username✨" in result.output
+    assert "Usage: main [OPTIONS] [✨username✨]" in result.output
     assert "Arguments" in result.output
-    assert "✨username✨" in result.output
     assert "[default: World]" in result.output
 
 

typer/core.py

@@ -383,7 +383,10 @@ def make_metavar(self, ctx: Union[click.Context, None] = None) -> str:
         # Modified version of click.core.Argument.make_metavar()
         # to include Argument name
         if self.metavar is not None:
-            return self.metavar
+            var = self.metavar
+            if not self.required and not var.startswith("["):
+                var = f"[{var}]"
+            return var
         var = (self.name or "").upper()
         if not self.required:
             var = f"[{var}]"