refactor(utils)!: drop filtermethods

The `utils.filtermethods` module contained a couple of unused
filtermethods that were used in old APIS models and referenced hardcoded
field names. They were all replaced by more flexible approaches by now.
The `construct_lookup` method that was part of the module can be useful
and was therefore salvaged and moved to the `utils.helpers` module.
The `test_filtermethods` module was renamed accordingly.

Closes: #790

apis_core/utils/helpers.py

@@ -202,3 +202,39 @@ def style_insert(text):
                     if show_a:
                         result += style_remove(a[a_start:a_end])
     return result
+
+
+def construct_lookup(value: str) -> tuple[str, str]:
+    """
+    Helper method to parse input values and construct field lookups
+    (https://docs.djangoproject.com/en/4.2/ref/models/querysets/#field-lookups)
+    Parses user input for wildcards and returns a tuple containing the
+    interpreted django lookup string and the trimmed value
+    E.g.
+
+    - ``example`` -> ``('__icontains', 'example')``
+    - ``*example*`` -> ``('__icontains', 'example')``
+    - ``*example`` -> ``('__iendswith', 'example')``
+    - ``example*``-> ``('__istartswith', 'example')``
+    - ``"example"`` -> ``('__iexact', 'example')``
+
+    :param str value: text to be parsed for ``*``
+    :return: a tuple containing the lookup type and the value without modifiers
+    """
+
+    if value.startswith("*") and not value.endswith("*"):
+        value = value[1:]
+        return "__iendswith", value
+
+    elif not value.startswith("*") and value.endswith("*"):
+        value = value[:-1]
+        return "__istartswith", value
+
+    elif value.startswith('"') and value.endswith('"'):
+        value = value[1:-1]
+        return "__iexact", value
+
+    else:
+        if value.startswith("*") and value.endswith("*"):
+            value = value[1:-1]
+        return "__icontains", value

apis_core/utils/test_filtermethods.py → apis_core/utils/test_helpers.py

@@ -3,7 +3,7 @@
 
 from django.test import TestCase
 
-from .filtermethods import construct_lookup
+from .helpers import construct_lookup
 
 lookups = {
     "*foo*": ("__icontains", "foo"),