fix: validate import identities and selected materials consistently

backend/tests/test_import_validation.py

@@ -0,0 +1,36 @@
+import pytest
+from pydantic import ValidationError
+
+from wisegrade.api import ImportConfirm, ProjectConfirm
+
+
+def project(**changes):
+    return {"relative_dir": "test/student", "student_no": "9000000001", "name": "学生甲", "topic": "机器人项目",
+            "files": [{"relative_path": "test/student/最终报告.pdf", "category": "final_report", "sha256": "a" * 64}], **changes}
+
+
+def test_confirm_normalizes_identity_before_validating():
+    result = ProjectConfirm.model_validate(project(student_no=" 9000000001 ", name=" 学生甲 ", topic=" 机器人项目 "))
+    assert (result.student_no, result.name, result.topic) == ("9000000001", "学生甲", "机器人项目")
+
+
+@pytest.mark.parametrize("changes", [
+    {"name": "   "}, {"topic": "   "}, {"student_no": "９００００００００１"}, {"files": []},
+    {"files": [{"relative_path": "test/student/a.pdf", "category": "unknown", "sha256": "a" * 64}]},
+    {"files": [{"relative_path": "test/student/a.pdf", "category": "final_report", "sha256": "a" * 64, "status": "ignored"}]},
+    {"files": [{"relative_path": f"test/student/{i}.pdf", "category": "final_report", "sha256": "a" * 64} for i in range(2)]},
+])
+def test_confirm_rejects_invalid_identity_or_selection(changes):
+    with pytest.raises(ValidationError):
+        ProjectConfirm.model_validate(project(**changes))
+
+
+def test_empty_import_is_rejected():
+    with pytest.raises(ValidationError):
+        ImportConfirm(course_version_id=1, projects=[])
+
+
+def test_ignored_unknown_material_does_not_block_valid_selection():
+    data = project()
+    data["files"].append({"relative_path": "test/student/foreign.pdf", "category": "unknown", "sha256": "b" * 64, "status": "ignored"})
+    assert len(ProjectConfirm.model_validate(data).files) == 2