Add tests

tests/test_form_max_fields_files_part_size.py

@@ -0,0 +1,89 @@
+from typing import List
+
+from fastapi import FastAPI, File, UploadFile
+from fastapi.testclient import TestClient
+
+app = FastAPI()
+
+
+@app.post("/", form_max_files=2, form_max_part_size=1024, form_max_fields=2)
+async def upload_files(files: List[UploadFile] = File(...)):
+    return {"filenames": [file.filename for file in files]}
+
+
+def test_form_max_files_send_one():
+    client = TestClient(app)
+
+    response = client.post(
+        "/",
+        files=[
+            ("files", ("file1.txt", b"file1 content", "text/plain")),
+        ],
+    )
+
+    assert response.status_code == 200, response.text
+    assert response.json() == {"filenames": ["file1.txt"]}
+
+
+def test_form_max_files_send_too_many():
+    client = TestClient(app)
+
+    response = client.post(
+        "/",
+        files=[
+            ("files", ("file1.txt", b"file1 content", "text/plain")),
+            ("files", ("file2.txt", b"file2 content", "text/plain")),
+            ("files", ("file3.txt", b"file3 content", "text/plain")),
+        ],
+    )
+
+    assert response.status_code == 400, response.text
+    assert response.json() == {
+        "detail": "Too many files. Maximum number of files is 2."
+    }
+
+
+def test_max_part_size_exceeds_custom_limit():
+    client = TestClient(app)
+
+    boundary = "------------------------4K1ON9fZkj9uCUmqLHRbbR"
+
+    multipart_data = (
+        f"--{boundary}\r\n"
+        f'Content-Disposition: form-data; name="small"\r\n\r\n'
+        "small content\r\n"
+        f"--{boundary}\r\n"
+        f'Content-Disposition: form-data; name="large"\r\n\r\n'
+        + ("x" * 1024 * 10 + "x")  # 1MB + 1 byte of data
+        + "\r\n"
+        f"--{boundary}--\r\n"
+    ).encode("utf-8")
+
+    headers = {
+        "Content-Type": f"multipart/form-data; boundary={boundary}",
+        "Transfer-Encoding": "chunked",
+    }
+
+    response = client.post("/", content=multipart_data, headers=headers)
+    assert response.status_code == 400
+    assert response.text == '{"detail":"Part exceeded maximum size of 1KB."}'
+
+
+def test_form_max_fields_exceeds_limit():
+    client = TestClient(app)
+
+    response = client.post(
+        "/",
+        files=[("files", ("file1.txt", b"file1 content", "text/plain"))],
+        data={
+            "field1": "value1",
+            "field2": "value2",
+            "field3": "value3",
+            "field4": "value4",
+        },
+    )
+
+    assert response.status_code == 400, response.text
+    assert response.json() == {
+        "detail": "Too many fields. Maximum number of fields is 2."
+    }