✨ Use Pydantic for parameter validation

pyproject.toml

@@ -33,6 +33,7 @@ classifiers = [
     "Programming Language :: Python :: 3.14",
 ]
 dependencies = [
+    "pydantic >=2.5.3",
     "shellingham >=1.3.0",
     "rich >=13.8.0",
     "annotated-doc >=0.0.2",

tests/test_others.py

@@ -450,7 +450,8 @@ def main(arg1, arg2: int, arg3: "int", arg4: bool = False, arg5: "bool" = False)
 
     result = runner.invoke(app, ["Hello", "2", "invalid"])
 
-    assert "Invalid value for 'ARG3': 'invalid' is not a valid integer" in result.output
+    assert "Invalid value for 'ARG3'" in result.output
+    assert "Input should be a valid integer" in result.output
     result = runner.invoke(app, ["Hello", "2", "3", "--arg4", "--arg5"])
     assert (
         "arg1: <class 'str'> Hello\narg2: <class 'int'> 2\narg3: <class 'int'> 3\narg4: <class 'bool'> True\narg5: <class 'bool'> True\n"

tests/test_tutorial/test_parameter_types/test_datetime/test_tutorial001.py

@@ -20,7 +20,7 @@ def test_type_repr():
 def test_help():
     result = runner.invoke(app, ["--help"])
     assert result.exit_code == 0
-    assert "[%Y-%m-%d|%Y-%m-%dT%H:%M:%S|%Y-%m-%d %H:%M:%S]" in result.output
+    assert "[%Y-%m-%d]" in result.output
 
 
 def test_main():
@@ -42,14 +42,8 @@ def test_main_datetime_object():
 def test_invalid():
     result = runner.invoke(app, ["july-19-1989"])
     assert result.exit_code != 0
-    assert (
-        "Invalid value for 'BIRTH:[%Y-%m-%d|%Y-%m-%dT%H:%M:%S|%Y-%m-%d %H:%M:%S]':"
-        in result.output
-    )
-    assert "'july-19-1989' does not match the formats" in result.output
-    assert "%Y-%m-%d" in result.output
-    assert "%Y-%m-%dT%H:%M:%S" in result.output
-    assert "%Y-%m-%d %H:%M:%S" in result.output
+    assert "Invalid value for 'BIRTH:[%Y-%m-%d]'" in result.output
+    assert "should be a valid datetime" in result.output
 
 
 def test_script():

tests/test_tutorial/test_parameter_types/test_index/test_tutorial001.py

@@ -44,7 +44,7 @@ def test_invalid():
     result = runner.invoke(app, ["Camila", "--age", "15.3"])
     assert result.exit_code != 0
     assert "Invalid value for '--age'" in result.output
-    assert "'15.3' is not a valid integer" in result.output
+    assert "Input should be a valid integer" in result.output
 
 
 def test_script():

tests/test_tutorial/test_parameter_types/test_number/test_tutorial001.py

@@ -67,24 +67,23 @@ def test_params(mod: ModuleType):
 def test_invalid_id(mod: ModuleType):
     result = runner.invoke(mod.app, ["1002"])
     assert result.exit_code != 0
-    assert (
-        "Invalid value for 'ID': 1002 is not in the range 0<=x<=1000." in result.output
-    )
+    assert "Invalid value for 'ID'" in result.output
+    assert "should be less than or equal to 1000" in result.output
 
 
 def test_invalid_age(mod: ModuleType):
     result = runner.invoke(mod.app, ["5", "--age", "15"])
     assert result.exit_code != 0
     assert "Invalid value for '--age'" in result.output
-    assert "15 is not in the range x>=18" in result.output
+    assert "should be greater than or equal to 18" in result.output
 
 
 def test_invalid_score(monkeypatch: pytest.MonkeyPatch, mod: ModuleType):
     monkeypatch.setattr(typer.core, "HAS_RICH", False)
     result = runner.invoke(mod.app, ["5", "--age", "20", "--score", "100.5"])
     assert result.exit_code != 0
     assert "Invalid value for '--score'" in result.output
-    assert "100.5 is not in the range x<=100." in result.output
+    assert "should be less than or equal to 100" in result.output
 
 
 def test_negative_score(mod: ModuleType):

tests/test_tutorial/test_parameter_types/test_number/test_tutorial002.py

@@ -25,9 +25,8 @@ def get_mod(request: pytest.FixtureRequest) -> ModuleType:
 def test_invalid_id(mod: ModuleType):
     result = runner.invoke(mod.app, ["1002"])
     assert result.exit_code != 0
-    assert (
-        "Invalid value for 'ID': 1002 is not in the range 0<=x<=1000" in result.output
-    )
+    assert "Invalid value for 'ID'" in result.output
+    assert "should be less than or equal to 1000" in result.output
 
 
 def test_clamped(mod: ModuleType):

tests/test_tutorial/test_parameter_types/test_uuid/test_tutorial001.py

@@ -35,10 +35,8 @@ def test_main_with_uuid_object():
 def test_invalid_uuid():
     result = runner.invoke(app, ["7479706572-72756c6573"])
     assert result.exit_code != 0
-    assert (
-        "Invalid value for 'USER_ID': '7479706572-72756c6573' is not a valid UUID"
-        in result.output
-    )
+    assert "Invalid value for 'USER_ID'" in result.output
+    assert "should be a valid UUID" in result.output
 
 
 def test_script():

tests/test_type_conversion.py

@@ -216,6 +216,40 @@ def custom_click_type(
     assert "2" in result.output
 
 
+@pytest.mark.parametrize(
+    ("cli_value", "expected"),
+    [
+        ("true", True),
+        ("false", False),
+        ("yes", True),
+        ("no", False),
+        ("1", True),
+        ("0", False),
+        ("on", True),
+        ("off", False),
+        ("t", True),
+        ("f", False),
+        ("y", True),
+        ("n", False),
+        ("", False),
+        (" true ", True),
+        (" FALSE ", False),
+        ("TRUE", True),
+        ("No", False),
+    ],
+)
+def test_bool_convert_valid(cli_value: str, expected: bool) -> None:
+    app = typer.Typer()
+
+    @app.command()
+    def main(value: bool):
+        print(value)
+
+    result = runner.invoke(app, [cli_value])
+    assert result.exit_code == 0
+    assert str(expected) in result.output
+
+
 def test_bool_convert_invalid():
     app = typer.Typer()
 
@@ -225,9 +259,7 @@ def main(value: bool):
 
     result = runner.invoke(app, ["maybe"])
     assert result.exit_code == 2
-    assert "is not a valid boolean" in result.output
-    assert "yes" in result.output
-    assert "false" in result.output
+    assert "Input should be a valid boolean" in result.output
 
 
 @pytest.mark.parametrize(
@@ -368,6 +400,22 @@ class CustomType:
     assert func_type.name == "CustomType"
 
 
+def test_int_rejects_float_default() -> None:
+    app = typer.Typer()
+
+    @app.command()
+    def main(age: int = typer.Option(15.3)):
+        typer.echo(age)
+
+    result = runner.invoke(app, ["--age", 42])
+    assert "42" in result.stdout
+
+    # Pydantic validation rejects floats as int instead of converting int(15.3) to 15
+    result = runner.invoke(app)
+    assert result.exit_code != 0
+    assert "Input should be a valid integer" in result.stderr
+
+
 @pytest.mark.parametrize(
     ("platform_case", "stdin_encoding", "filesystem_encoding"),
     [