sort choices for more natural human use

Sorting the choices in forms helps with a more natural selection process

tests/test_choices.py

@@ -37,12 +37,21 @@ def tzs3_names():
     ]
 
 
+@pytest.fixture
+def tzs3_names_sorted():
+    yield [
+        "America/Argentina/Buenos_Aires",
+        "America/Los_Angeles",
+        "Europe/London",
+    ]
+
+
 @pytest.fixture
 def tzs3_standard_displays():
     yield [
+        "America/Argentina/Buenos Aires",
         "America/Los Angeles",
         "Europe/London",
-        "America/Argentina/Buenos Aires",
     ]
 
 
@@ -104,10 +113,11 @@ def test_with_gmt_offset_transition_backward(use_pytz, utc_tzobj):
     assert with_gmt_offset(tz_names, now=after, use_pytz=use_pytz) == [("Europe/London", "GMT+00:00 Europe/London")]
 
 
-def test_standard_using_timezone_names(tzs3_names, tzs3_standard_displays):
-    assert standard(tzs3_names) == list(zip(tzs3_names, tzs3_standard_displays))
+def test_standard_using_timezone_names(tzs3_names, tzs3_names_sorted, tzs3_standard_displays):
+    assert standard(tzs3_names) == list(zip(tzs3_names_sorted, tzs3_standard_displays))
 
 
-def test_standard_using_timezone_objects(tzs3_names, tzs3_standard_displays, to_tzobj):
+def test_standard_using_timezone_objects(tzs3_names, tzs3_names_sorted, tzs3_standard_displays, to_tzobj):
     tzs3_objects = [to_tzobj(tz) for tz in tzs3_names]
-    assert standard(tzs3_objects) == list(zip(tzs3_objects, tzs3_standard_displays))
+    tzs3_objects_sorted = [to_tzobj(tz) for tz in tzs3_names_sorted]
+    assert standard(tzs3_objects) == list(zip(tzs3_objects_sorted, tzs3_standard_displays))

tests/test_choices_display_option.py

@@ -1,3 +1,5 @@
+from collections import Counter
+
 import pytest
 from django import forms
 from django.db import models
@@ -104,7 +106,7 @@ def test_form_field_invalid_choices_display(use_pytz):
 def test_form_field_none(ChoicesDisplayForm, base_tzstrs):
     form = ChoicesDisplayForm()
     values, displays = zip(*form.fields["tz_none"].choices)
-    assert values == tuple(base_tzstrs)
+    assert sorted(values) == sorted(base_tzstrs)
     assert displays[values.index("America/Los_Angeles")] == "America/Los Angeles"
     assert displays[values.index("Asia/Kolkata")] == "Asia/Kolkata"
 
@@ -136,10 +138,10 @@ def test_form_field_limited_none(ChoicesDisplayForm):
 def test_form_field_limited_standard(ChoicesDisplayForm):
     form = ChoicesDisplayForm()
     assert form.fields["tz_limited_standard"].choices == [
-        ("Asia/Tokyo", "Asia/Tokyo"),
-        ("Asia/Dubai", "Asia/Dubai"),
-        ("America/Argentina/Buenos_Aires", "America/Argentina/Buenos Aires"),
         ("Africa/Nairobi", "Africa/Nairobi"),
+        ("America/Argentina/Buenos_Aires", "America/Argentina/Buenos Aires"),
+        ("Asia/Dubai", "Asia/Dubai"),
+        ("Asia/Tokyo", "Asia/Tokyo"),
     ]
 
 
@@ -156,7 +158,7 @@ def test_form_field_limited_with_gmt_offset(ChoicesDisplayForm):
 def test_model_form_field_none(ChoicesDisplayModelForm, to_tzobj, base_tzobjs):
     form = ChoicesDisplayModelForm()
     values, displays = zip(*form.fields["tz_none"].choices)
-    assert values == ("",) + tuple(base_tzobjs)
+    assert Counter(values) == Counter(("",) + tuple(base_tzobjs))
     assert displays[values.index(to_tzobj("America/Los_Angeles"))] == "America/Los Angeles"
     assert displays[values.index(to_tzobj("Asia/Kolkata"))] == "Asia/Kolkata"
 
@@ -192,10 +194,10 @@ def test_moel_form_field_limited_standard(ChoicesDisplayModelForm, to_tzobj):
     form = ChoicesDisplayModelForm()
     assert form.fields["tz_limited_standard"].choices == [
         ("", "---------"),
-        (to_tzobj("Asia/Tokyo"), "Asia/Tokyo"),
-        (to_tzobj("Asia/Dubai"), "Asia/Dubai"),
-        (to_tzobj("America/Argentina/Buenos_Aires"), "America/Argentina/Buenos Aires"),
         (to_tzobj("Africa/Nairobi"), "Africa/Nairobi"),
+        (to_tzobj("America/Argentina/Buenos_Aires"), "America/Argentina/Buenos Aires"),
+        (to_tzobj("Asia/Dubai"), "Asia/Dubai"),
+        (to_tzobj("Asia/Tokyo"), "Asia/Tokyo"),
     ]
 
 

timezone_field/choices.py

@@ -3,6 +3,28 @@
 from timezone_field.backends import get_tz_backend
 
 
+def normalize_standard(tztuple):
+    """Normalize timezone names by replacing special characters with space.
+
+    For proper sorting, using spaces makes comparisons more consistent.
+
+    :param str tztuple: tuple of timezone and representation
+    """
+    return tztuple[1].translate(str.maketrans({"-": " ", "_": " "}))
+
+
+def normalize_gmt(tztuple):
+    """Normalize timezone GMT names for sorting.
+
+    For proper sorting, using GMT values as a positive or negative number.
+
+    :param str tztuple: tuple of timezone and representation
+    """
+    gmt = tztuple[1].split()[0]
+    cmp = gmt.replace("GMT", "").replace(":", "")
+    return int(cmp)
+
+
 def standard(timezones):
     """
     Given a list of timezones (either strings of timezone objects),
@@ -14,7 +36,7 @@ def standard(timezones):
     for tz in timezones:
         tz_str = str(tz)
         choices.append((tz, tz_str.replace("_", " ")))
-    return choices
+    return sorted(choices, key=normalize_standard)
 
 
 def with_gmt_offset(timezones, now=None, use_pytz=None):
@@ -41,4 +63,4 @@ def with_gmt_offset(timezones, now=None, use_pytz=None):
         _choices.append((delta, tz, display))
     _choices.sort(key=lambda x: x[0])
     choices = [(one, two) for zero, one, two in _choices]
-    return choices
+    return sorted(choices, key=normalize_gmt)