[importers] Add error_log to surface import errors

tests/birds_tests/test_importer.py

@@ -1,3 +1,4 @@
+import tempfile
 from datetime import timedelta
 
 import pytest
@@ -128,6 +129,23 @@ class TestBirdingCSVImportModel:
         assert imp.import_type == "Birding CSV"
         assert "Birding" in str(imp)
 
+    def test_record_error(self, db, user):
+        imp = BirdingCSVImport.objects.create(user=user)
+        assert imp.error_log is None
+        imp.record_error("test error")
+        imp.refresh_from_db()
+        assert imp.error_log is not None
+        assert "test error" in imp.error_log
+
+    def test_record_error_appends(self, db, user):
+        imp = BirdingCSVImport.objects.create(user=user)
+        imp.record_error("first error")
+        imp.record_error("second error")
+        imp.refresh_from_db()
+        assert imp.error_log.count("\n") == 1
+        assert "first error" in imp.error_log
+        assert "second error" in imp.error_log
+
     @pytest.mark.django_db(transaction=True)
     def test_process_via_model(self, user, birding_csv_file):
         imp = BirdingCSVImport.objects.create(user=user)
@@ -137,3 +155,35 @@ class TestBirdingCSVImportModel:
         imp.refresh_from_db()
         assert imp.process_count == 1
         assert imp.processed_finished is not None
+
+    def test_record_error_on_bad_csv(self, user, db):
+        content = """Species,Count,Location,Observation Type,Observation Date,Start Time,Duration,Distance,Area,Party Size,Complete Checklist,# of species,Details
+Canada Goose,6,Test Park,Stationary,"Bad Date",4:15 PM,9 minute(s),,,4,true,4 species,
+"""
+        with tempfile.NamedTemporaryFile(
+            mode="w", suffix=".csv", delete=False, encoding="utf-8"
+        ) as f:
+            f.write(content)
+            file_path = f.name
+
+        errors = []
+        scrobbles = import_birding_csv(file_path, user.id, record_error=errors.append)
+        assert len(scrobbles) == 0
+        assert len(errors) == 1
+        assert "Could not parse date/time" in errors[0]
+
+    def test_record_error_on_bad_location(self, user, db):
+        content = """Species,Count,Location,Observation Type,Observation Date,Start Time,Duration,Distance,Area,Party Size,Complete Checklist,# of species,Details
+Canada Goose,6,,Stationary,"May 10, 2026",4:15 PM,9 minute(s),,,4,true,4 species,
+"""
+        with tempfile.NamedTemporaryFile(
+            mode="w", suffix=".csv", delete=False, encoding="utf-8"
+        ) as f:
+            f.write(content)
+            file_path = f.name
+
+        errors = []
+        scrobbles = import_birding_csv(file_path, user.id, record_error=errors.append)
+        assert len(scrobbles) == 0
+        assert len(errors) == 1
+        assert "Skipping rows with no location" in errors[0]