1 files changed, 45 insertions, 0 deletions
diff --git a/tests/test_valid.py b/tests/test_valid.py
new file mode 100644
index 0000000..45f9bb5
--- /dev/null
+++ b/tests/test_valid.py
@@ -0,0 +1,45 @@
+from decimal import Decimal
+from math import isnan
+from pathlib import Path
+from typing import Union
+
+import pytest
+import tomli
+
+import tomli_w
+
+COMPLIANCE_DIR = Path(__file__).parent / "data" / "toml-lang-compliance" / "valid"
+EXTRAS_DIR = Path(__file__).parent / "data" / "extras" / "valid"
+
+VALID_FILES = tuple(COMPLIANCE_DIR.glob("**/*.toml")) + tuple(
+    EXTRAS_DIR.glob("**/*.toml")
+)
+
+
+@pytest.mark.parametrize(
+    "valid",
+    VALID_FILES,
+    ids=[p.stem for p in VALID_FILES],
+)
+def test_valid(valid):
+    if valid.stem in {"qa-array-inline-nested-1000", "qa-table-inline-nested-1000"}:
+        pytest.xfail("This much recursion is not supported")
+    original_str = valid.read_bytes().decode()
+    original_data = tomli.loads(original_str)
+    dump_str = tomli_w.dumps(original_data)
+    after_dump_data = tomli.loads(dump_str)
+    assert replace_nans(after_dump_data) == replace_nans(original_data)
+
+
+NAN = object()
+
+
+def replace_nans(cont: Union[dict, list]) -> Union[dict, list]:
+    """Replace NaNs with a sentinel object to fix the problem that NaN is not
+    equal to another NaN."""
+    for k, v in cont.items() if isinstance(cont, dict) else enumerate(cont):
+        if isinstance(v, (float, Decimal)) and isnan(v):
+            cont[k] = NAN
+        elif isinstance(v, dict) or isinstance(v, list):
+            cont[k] = replace_nans(cont[k])
+    return cont