Move from toml to tomli (#2118)

2 files changed, 6 insertions, 4 deletions

diff --git a/src/tox/config/source/legacy_toml.py b/src/tox/config/source/legacy_toml.py
index a100ff66..4935eaba 100644
--- a/src/tox/config/source/legacy_toml.py
+++ b/src/tox/config/source/legacy_toml.py
@@ -1,6 +1,6 @@
 from pathlib import Path
 
-import toml
+import tomli
 
 from .ini import IniSource
 
@@ -11,7 +11,8 @@ class LegacyToml(IniSource):
     def __init__(self, path: Path):
         if path.name != self.FILENAME or not path.exists():
             raise ValueError
-        toml_content = toml.loads(path.read_text())
+        with path.open() as file_handler:
+            toml_content = tomli.load(file_handler)
         try:
             content = toml_content["tool"]["tox"]["legacy_tox_ini"]
         except KeyError:
diff --git a/src/tox/util/pep517/frontend.py b/src/tox/util/pep517/frontend.py
index 7310b68c..e1c8f4bf 100644
--- a/src/tox/util/pep517/frontend.py
+++ b/src/tox/util/pep517/frontend.py
@@ -9,7 +9,7 @@ from time import sleep
 from typing import Any, Dict, Iterator, List, NamedTuple, NoReturn, Optional, Tuple, cast
 from zipfile import ZipFile
 
-import toml
+import tomli
 from packaging.requirements import Requirement
 
 _HERE = Path(__file__).parent
@@ -106,7 +106,8 @@ class Frontend(ABC):
     ) -> Tuple[Path, Tuple[Path, ...], str, Optional[str], Tuple[Requirement, ...], bool]:
         py_project_toml = folder / "pyproject.toml"
         if py_project_toml.exists():
-            py_project = toml.load(py_project_toml)
+            with py_project_toml.open() as file_handler:
+                py_project = tomli.load(file_handler)
             build_system = py_project.get("build-system", {})
             if "backend-path" in build_system:
                 backend_paths: Tuple[Path, ...] = tuple(folder / p for p in build_system["backend-path"])