Add 4 extra tests for edge cases

tests/test_others.py

@@ -0,0 +1,51 @@
+from typing import Optional
+
+import typer
+from typer.main import solve_typer_info_defaults, solve_typer_info_help
+from typer.models import TyperInfo
+from typer.testing import CliRunner
+
+runner = CliRunner()
+
+
+def test_optional():
+    app = typer.Typer()
+
+    @app.command()
+    def opt(user: Optional[str] = None):
+        if user:
+            typer.echo(f"User: {user}")
+        else:
+            typer.echo("No user")
+
+    result = runner.invoke(app)
+    assert result.exit_code == 0
+    assert "No user" in result.output
+
+    result = runner.invoke(app, ["--user", "Camila"])
+    assert result.exit_code == 0
+    assert "User: Camila" in result.output
+
+
+def test_no_type():
+    app = typer.Typer()
+
+    @app.command()
+    def no_type(user):
+        typer.echo(f"User: {user}")
+
+    result = runner.invoke(app, ["Camila"])
+    assert result.exit_code == 0
+    assert "User: Camila" in result.output
+
+
+def test_help_from_info():
+    # Mainly for coverage/completeness
+    value = solve_typer_info_help(TyperInfo())
+    assert value is None
+
+
+def test_defaults_from_info():
+    # Mainly for coverage/completeness
+    value = solve_typer_info_defaults(TyperInfo())
+    assert value