Add missing constraints for read_status in ReadThrough

bookwyrm/migrations/0152_readthrough_read_status_constraints.py

@@ -0,0 +1,37 @@
+# Generated by Django 3.2.20 on 2023-11-13 23:12
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("bookwyrm", "0152_readthrough_stopped_date_remove"),
+    ]
+
+    operations = [
+        migrations.AddConstraint(
+            model_name="readthrough",
+            constraint=models.CheckConstraint(
+                check=models.Q(
+                    ("finish_date__isnull", False),
+                    ("read_status", "reading"),
+                    _negated=True,
+                ),
+                name="currently-reading",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="readthrough",
+            constraint=models.CheckConstraint(
+                check=models.Q(
+                    models.Q(("read_status", "to-read"), _negated=True),
+                    models.Q(
+                        ("finish_date__isnull", True), ("start_date__isnull", True)
+                    ),
+                    _connector="OR",
+                ),
+                name="to-read",
+            ),
+        ),
+    ]

bookwyrm/migrations/0152_auto_20220704_0135.py → bookwyrm/migrations/0152_readthrough_stopped_date_remove.py

@@ -26,7 +26,7 @@ def unmerge_finish_stopped_dates(apps, schema_editor):
 class Migration(migrations.Migration):
 
     dependencies = [
-        ("bookwyrm", "0151_auto_20220703_1842"),
+        ("bookwyrm", "0152_readthrough_read_status_add"),
     ]
 
     operations = [

bookwyrm/models/readthrough.py

@@ -70,11 +70,16 @@ class Meta:
             ),
             # Can't be actively reading the same book twice
             # Currently reading status can't have stopped date
-            # models.CheckConstraint(
-            #    check=~Q(read_status="to-read", finish_date__isnull=False),
-            #    name="currently-reading"
-            # ),
+            models.CheckConstraint(
+                name="currently-reading",
+                check=~Q(read_status="reading", finish_date__isnull=False),
+            ),
             # Can't want to read and have started or finished dates
+            models.CheckConstraint(
+                name="to-read",
+                check=~Q(read_status="to-read")
+                | Q(start_date__isnull=True, finish_date__isnull=True),
+            ),
         ]
         ordering = ("-start_date",)
 

bookwyrm/tests/models/test_readthrough_model.py

@@ -1,9 +1,9 @@
 """ testing models """
-import datetime
+from datetime import timedelta
 from unittest.mock import patch
 from django.test import TestCase
 from django.core.exceptions import ValidationError
-from django.db import IntegrityError
+from django.db import IntegrityError, transaction
 from django.utils import timezone
 
 from bookwyrm import models
@@ -28,30 +28,60 @@ def setUp(self):
 
 
 class ReadThroughConstraints(ReadThroughTestBase):
-    def _assert_create(self, start_date=None, finish_date=None, /):
+    def _assert_create(self, start_date, finish_date=None, /, read_status="read"):
+        """create ReadThrough helper"""
         self.assertIsNotNone(
             models.ReadThrough.objects.create(
                 user=self.user,
                 book=self.edition,
                 start_date=start_date,
                 finish_date=finish_date,
+                read_status=read_status,
             )
         )
 
+    def _fail_create(self, start_date, finish_date, /, read_status):
+        """expected failure in ReadThrough creation"""
+        with self.assertRaises(IntegrityError):
+            self._assert_create(start_date, finish_date, read_status)
+
     def test_valid_dates(self):
         """valid combinations of start_date and finish_date"""
         start = timezone.now()
+
         self._assert_create(None, None)
         self._assert_create(start, None)
         self._assert_create(None, start)
-        self._assert_create(start, start + datetime.timedelta(days=1))
+        self._assert_create(start, start + timedelta(days=1))
         self._assert_create(start, start)
 
+        self._assert_create(None, None, "to-read")
+        self._assert_create(None, None, "reading")
+        self._assert_create(start, None, "reading")
+
     def test_chronology_constraint(self):
         """finish_date >= start_date"""
         start = timezone.now()
-        with self.assertRaises(IntegrityError):
-            self._assert_create(start, start - datetime.timedelta(days=2))
+        before_start = start - timedelta(days=2)
+
+        self._fail_create(start, before_start, "read")
+
+    def test_currently_reading_constraint(self):
+        """no finish date allowed for `reading`"""
+        start = finish = timezone.now()
+        self._fail_create(start, finish, "reading")
+
+    def test_to_read_constraint(self):
+        """no dates allowed for `to-read`"""
+        start = finish = timezone.now()
+        test_cases = [
+            ("start date", start, None),
+            ("finish date", None, start),
+            ("start and finish", start, finish),
+        ]
+        for desc, beg, end in test_cases:
+            with self.subTest(desc), transaction.atomic():
+                self._fail_create(beg, end, "to-read")
 
 
 class ReadThroughProgressUpdates(ReadThroughTestBase):