refactor: move generate_slug to logic

eav/fields.py

@@ -1,27 +1,12 @@
 import re
-import secrets
-import string
 
 from django.core.exceptions import ValidationError
 from django.db import models
-from django.utils.text import slugify
 from django.utils.translation import gettext_lazy as _
 
 from eav.forms import CSVFormField
 
 
-def generate_slug(name: str) -> str:
-    """Generates a valid slug based on ``name``."""
-    slug = slugify(name, allow_unicode=False)
-
-    if not slug:
-        # Fallback to ensure a slug is always generated by using a random one
-        chars = string.ascii_lowercase + string.digits
-        randstr = ''.join(secrets.choice(chars) for _ in range(8))
-        slug = 'rand-{0}'.format(randstr)
-    return slug.encode('utf-8', 'surrogateescape').decode()
-
-
 class EavSlugField(models.SlugField):
     """
     The slug field used by :class:`~eav.models.Attribute`

eav/logic/slug.py

@@ -0,0 +1,22 @@
+import secrets
+import string
+from typing import Final
+
+from django.utils.text import slugify
+
+SLUGFIELD_MAX_LENGTH: Final = 50
+
+
+def generate_slug(name: str) -> str:
+    """Generates a valid slug based on ``name``."""
+    slug = slugify(name, allow_unicode=False)
+
+    if not slug:
+        # Fallback to ensure a slug is always generated by using a random one
+        chars = string.ascii_lowercase + string.digits
+        randstr = ''.join(secrets.choice(chars) for _ in range(8))
+        slug = 'rand-{0}'.format(randstr)
+
+    slug = slug.encode('utf-8', 'surrogateescape').decode()
+
+    return slug[:SLUGFIELD_MAX_LENGTH]

eav/models.py

@@ -10,6 +10,7 @@ optional metaclass for each eav model class.
 """
 
 from copy import copy
+from typing import Final
 
 from django.contrib.contenttypes import fields as generic
 from django.contrib.contenttypes.models import ContentType
@@ -22,8 +23,9 @@ from django.utils.translation import gettext_lazy as _
 
 from eav import register
 from eav.exceptions import IllegalAssignmentException
-from eav.fields import CSVField, EavDatatypeField, EavSlugField, generate_slug
+from eav.fields import CSVField, EavDatatypeField
 from eav.logic.entity_pk import get_entity_pk_type
+from eav.logic.slug import SLUGFIELD_MAX_LENGTH, generate_slug
 from eav.validators import (
     validate_bool,
     validate_csv,
@@ -42,6 +44,9 @@ except ImportError:
     from django_jsonfield_backport.models import JSONField
 
 
+CHARFIELD_LENGTH: Final = 100
+
+
 class EnumValue(models.Model):
     """
     *EnumValue* objects are the value 'choices' to multiple choice *TYPE_ENUM*
@@ -73,7 +78,7 @@ class EnumValue(models.Model):
         _('Value'),
         db_index=True,
         unique=True,
-        max_length=50,
+        max_length=SLUGFIELD_MAX_LENGTH,
     )
 
     def __str__(self):
@@ -94,7 +99,7 @@ class EnumGroup(models.Model):
     See :class:`EnumValue` for an example.
     """
 
-    name = models.CharField(_('Name'), unique=True, max_length=100)
+    name = models.CharField(_('Name'), unique=True, max_length=CHARFIELD_LENGTH)
     values = models.ManyToManyField(EnumValue, verbose_name=_('Enum group'))
 
     def __str__(self):
@@ -191,7 +196,7 @@ class Attribute(models.Model):
 
     name = models.CharField(
         verbose_name=_('Name'),
-        max_length=100,
+        max_length=CHARFIELD_LENGTH,
         help_text=_('User-friendly attribute name'),
     )
 
@@ -202,7 +207,7 @@ class Attribute(models.Model):
     """
     slug = models.SlugField(
         verbose_name=_('Slug'),
-        max_length=50,
+        max_length=SLUGFIELD_MAX_LENGTH,
         db_index=True,
         unique=True,
         help_text=_('Short unique attribute label'),

tests/test_logic.py

@@ -0,0 +1,20 @@
+from hypothesis import given
+from hypothesis import strategies as st
+
+from eav.logic.slug import SLUGFIELD_MAX_LENGTH, generate_slug
+
+
+@given(st.text())
+def test_generate_slug(name: str) -> None:
+    """Ensures slug generation works properly."""
+    slug = generate_slug(name)
+
+    assert slug
+
+
+@given(st.text(min_size=SLUGFIELD_MAX_LENGTH))
+def test_generate_long_slug_text(name: str) -> None:
+    """Ensures a slug isn't generated longer than maximum allowed length."""
+    slug = generate_slug(name)
+
+    assert len(slug) <= SLUGFIELD_MAX_LENGTH