added unique constraint to GuidVersionsThrough

osf/migrations/0026_guidversionsthrough_unique_guid_version.py

@@ -0,0 +1,17 @@
+# Generated by Django 4.2.15 on 2024-12-12 12:26
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('osf', '0025_versioned_guid_for_preprints_doi_versioning'),
+    ]
+
+    operations = [
+        migrations.AddConstraint(
+            model_name='guidversionsthrough',
+            constraint=models.UniqueConstraint(fields=('guid', 'version'), name='unique_guid_version'),
+        ),
+    ]

osf/models/base.py

@@ -9,7 +9,7 @@
 from django.core.exceptions import MultipleObjectsReturned
 from django.core.exceptions import ValidationError as DjangoValidationError
 from django.db import connections, models
-from django.db.models import ForeignKey
+from django.db.models import ForeignKey, UniqueConstraint
 from django.db.models.query import QuerySet
 from django.db.models.signals import post_save
 from django.dispatch import receiver
@@ -273,6 +273,10 @@ class GuidVersionsThrough(BaseModel):
     version = models.PositiveIntegerField(null=True, blank=True)
     is_rejected = models.BooleanField(default=False)
 
+    class Meta:
+        constraints = [
+            UniqueConstraint(fields=['guid', 'version'], name='unique_guid_version')
+        ]
 
 class BlackListGuid(BaseModel):
     id = models.AutoField(primary_key=True)

osf/models/preprint.py

@@ -597,7 +597,7 @@ def csl(self):  # formats node information into CSL format for citation parsing
 
     @property
     def is_latest_version(self):
-        if not self.date_published:
+        if self.machine_state != 'initial' and not self.date_published:
             return False
         return self.versioned_guids.first().guid.referent.version == self.version