fix: report malformed pyproject TOML as a CLI error

src/fastapi_cli/cli.py

@@ -165,6 +165,10 @@ def _run(
 
         try:
             config = FastAPIConfig.resolve(entrypoint=entrypoint)
+        except FastAPICLIException as e:
+            toolkit.print_line()
+            toolkit.print(f"[error]{e}")
+            raise typer.Exit(code=1) from None
         except ValidationError as e:
             toolkit.print_line()
             toolkit.print("[error]Invalid configuration in pyproject.toml:")

src/fastapi_cli/config.py

@@ -4,6 +4,8 @@
 
 from pydantic import BaseModel, StrictStr
 
+from fastapi_cli.exceptions import FastAPICLIException
+
 logger = logging.getLogger(__name__)
 
 
@@ -29,7 +31,10 @@ def _read_pyproject_toml(cls) -> dict[str, Any]:
                 return {}
 
         with open(pyproject_path, "rb") as f:
-            data = tomllib.load(f)
+            try:
+                data = tomllib.load(f)
+            except tomllib.TOMLDecodeError as e:
+                raise FastAPICLIException(f"Invalid TOML in pyproject.toml: {e}") from e
 
             return data.get("tool", {}).get("fastapi", {})  # type: ignore[no-any-return]
 

tests/test_cli_pyproject.py

@@ -1,6 +1,7 @@
 from pathlib import Path
 from unittest.mock import patch
 
+import pytest
 import uvicorn
 from typer.testing import CliRunner
 
@@ -12,6 +13,26 @@
 assets_path = Path(__file__).parent / "assets"
 
 
+@pytest.mark.parametrize("command", ["dev", "run"])
+@pytest.mark.parametrize(
+    "content",
+    [
+        "[tool.fastapi\n",
+        '[tool.fastapi]\nentrypoint = "main:app"\nentrypoint = "other:app"\n',
+    ],
+)
+def test_pyproject_toml_syntax_error(
+    command: str, content: str, tmp_path: Path
+) -> None:
+    (tmp_path / "pyproject.toml").write_text(content)
+    with changing_dir(tmp_path), patch.object(uvicorn, "run") as mock_run:
+        result = runner.invoke(app, [command])
+
+    assert result.exit_code == 1
+    assert "Invalid TOML in pyproject.toml:" in result.output
+    mock_run.assert_not_called()
+
+
 def test_dev_with_pyproject_app_config_uses() -> None:
     with (
         changing_dir(assets_path / "pyproject_config"),