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MyFastHtml/tests/core/test_bindings.py

384 lines
10 KiB
Python

from dataclasses import dataclass
import pytest
from fasthtml.components import Label, Input
from myutils.observable import collect_return_values
from myfasthtml.core.bindings import (
BindingsManager,
Binding,
DetectionMode,
UpdateMode,
BooleanConverter
)
@dataclass
class Data:
value: str = "Hello World"
@pytest.fixture(autouse=True)
def reset_binding_manager():
BindingsManager.reset()
@pytest.fixture()
def data():
return Data()
def test_i_can_register_a_binding(data):
binding = Binding(data, "value")
assert binding.id is not None
assert binding.data is data
assert binding.data_attr == 'value'
def test_i_can_register_a_binding_with_default_attr(data):
binding = Binding(data)
assert binding.id is not None
assert binding.data is data
assert binding.data_attr == 'value'
def test_i_can_retrieve_a_registered_binding(data):
elt = Label("hello", id="label_id")
binding = Binding(data).bind_ft(elt, name="label_name")
assert BindingsManager.get_binding(binding.id) is binding
def test_i_can_reset_bindings(data):
elt = Label("hello", id="label_id")
Binding(data).bind_ft(elt, name="label_name")
assert len(BindingsManager.bindings) != 0
BindingsManager.reset()
assert len(BindingsManager.bindings) == 0
def test_i_can_bind_an_element_to_a_binding(data):
elt = Label("hello", id="label_id")
Binding(data).bind_ft(elt, name="label_name")
data.value = "new value"
assert elt.children[0] == "new value"
assert elt.attrs["hx-swap-oob"] == "true"
assert elt.attrs["id"] == "label_id"
def test_i_can_bind_an_element_attr_to_a_binding(data):
elt = Input(value="some value", id="input_id")
Binding(data).bind_ft(elt, name="input_name", attr="value")
data.value = "new value"
assert elt.attrs["value"] == "new value"
assert elt.attrs["hx-swap-oob"] == "true"
assert elt.attrs["id"] == "input_id"
def test_bound_element_has_an_id():
elt = Label("hello")
assert elt.attrs.get("id", None) is None
Binding(Data()).bind_ft(elt, name="label_name")
assert elt.attrs.get("id", None) is not None
def test_i_can_collect_updates_values(data):
elt = Label("hello")
Binding(data).bind_ft(elt, name="label_name")
data.value = "new value"
collected = collect_return_values(data)
assert collected == [elt]
# a second time to ensure no side effect
data.value = "another value"
collected = collect_return_values(data)
assert collected == [elt]
def test_i_can_react_to_value_change(data):
elt = Input(name="input_elt", value="hello")
binding = Binding(data).bind_ft(elt, name="input_elt", attr="value")
res = binding.update({"input_elt": "new value"})
assert len(res) == 1
def test_i_do_not_react_to_other_value_change(data):
elt = Input(name="input_elt", value="hello")
binding = Binding(data).bind_ft(elt, name="input_elt", attr="value")
res = binding.update({"other_input_elt": "new value"})
assert res is None
def test_i_can_react_to_attr_presence(data):
elt = Input(name="input_elt", type="checkbox")
binding = Binding(data).bind_ft(
elt,
name="input_elt",
attr="checked",
detection_mode=DetectionMode.AttributePresence
)
res = binding.update({"checked": "true"})
assert len(res) == 1
def test_i_can_react_to_attr_non_presence(data):
elt = Input(name="input_elt", type="checkbox")
binding = Binding(data).bind_ft(
elt,
name="input_elt",
attr="checked",
detection_mode=DetectionMode.AttributePresence
)
res = binding.update({})
assert len(res) == 1
def test_i_can_create_a_binding_without_activation(data):
"""
A binding created without calling bind_ft should not be active.
"""
binding = Binding(data, "value")
assert binding._is_active is False
assert binding.ft is None
assert binding.ft_name is None
assert binding.ft_attr is None
assert BindingsManager.get_binding(binding.id) is None
def test_i_can_activate_binding_via_bind_ft(data):
"""
Calling bind_ft should automatically activate the binding.
"""
elt = Label("hello", id="label_id")
binding = Binding(data, "value")
binding.bind_ft(elt, name="label_name")
assert binding._is_active is True
assert binding.ft is elt
assert binding.ft_name == "label_name"
assert BindingsManager.get_binding(binding.id) is binding
def test_i_cannot_notify_when_not_active(data):
"""
A non-active binding should not update the UI when data changes.
"""
elt = Label("hello", id="label_id")
binding = Binding(data, "value")
binding.ft = elt
binding.ft_name = "label_name"
# Change data without activating the binding
result = binding.notify("old", "new")
assert result is None
assert elt.children[0] == "hello" # Should not have changed
def test_i_can_deactivate_a_binding(data):
"""
Deactivating a binding should clean up observers and unregister it.
"""
elt = Label("hello", id="label_id")
binding = Binding(data, "value").bind_ft(elt, name="label_name")
assert binding._is_active is True
assert BindingsManager.get_binding(binding.id) is binding
binding.deactivate()
assert binding._is_active is False
assert BindingsManager.get_binding(binding.id) is None
def test_i_can_reactivate_a_binding(data):
"""
After deactivation, a binding can be reactivated by calling bind_ft again.
"""
elt1 = Label("hello", id="label_id_1")
binding = Binding(data, "value").bind_ft(elt1, name="label_name_1")
binding.deactivate()
assert binding._is_active is False
elt2 = Label("world", id="label_id_2")
binding.bind_ft(elt2, name="label_name_2")
assert binding._is_active is True
assert binding.ft is elt2
assert binding.ft_name == "label_name_2"
def test_bind_ft_deactivates_before_reconfiguring(data):
"""
Calling bind_ft on an active binding should deactivate it first,
then reconfigure and reactivate.
"""
elt1 = Label("hello", id="label_id_1")
elt2 = Label("world", id="label_id_2")
binding = Binding(data, "value").bind_ft(elt1, name="label_name_1")
# Change data to verify old binding works
data.value = "updated"
assert elt1.children[0] == "updated"
# Reconfigure with new element
binding.bind_ft(elt2, name="label_name_2")
# Change data again
data.value = "final"
# Old element should not update
assert elt1.children[0] == "updated"
# New element should update
assert elt2.children[0] == "final"
def test_deactivate_can_be_called_multiple_times(data):
"""
Calling deactivate multiple times should be safe (idempotent).
"""
elt = Label("hello", id="label_id")
binding = Binding(data, "value").bind_ft(elt, name="label_name")
binding.deactivate()
binding.deactivate() # Should not raise an error
binding.deactivate() # Should not raise an error
assert binding._is_active is False
def test_i_cannot_activate_without_configuration(data):
"""
Calling activate directly without proper configuration should raise ValueError.
"""
binding = Binding(data, "value")
with pytest.raises(ValueError, match="ft element is required"):
binding.activate()
def test_activation_validates_strategies(data):
"""
Activation should fail if detection/update strategies are not initialized.
"""
elt = Label("hello", id="label_id")
binding = Binding(data, "value")
binding.ft = elt
binding.ft_name = "label_name"
with pytest.raises(ValueError, match="detection strategy not initialized"):
binding.activate()
def test_i_can_chain_bind_ft_calls(data):
"""
bind_ft should return self for method chaining.
"""
elt = Label("hello", id="label_id")
binding = Binding(data, "value").bind_ft(elt, name="label_name")
assert isinstance(binding, Binding)
assert binding._is_active is True
def test_bind_ft_updates_optional_parameters(data):
"""
bind_ft should update optional parameters if provided.
"""
elt = Input(name="input_elt", type="checkbox")
binding = Binding(data, "value")
binding.bind_ft(
elt,
name="input_elt",
attr="checked",
data_converter=BooleanConverter(),
detection_mode=DetectionMode.AttributePresence,
update_mode=UpdateMode.AttributePresence
)
assert binding.detection_mode == DetectionMode.AttributePresence
assert binding.update_mode == UpdateMode.AttributePresence
assert isinstance(binding.data_converter, BooleanConverter)
def test_deactivated_binding_does_not_update_on_data_change(data):
"""
After deactivation, changes to data should not update the UI element.
"""
elt = Label("hello", id="label_id")
binding = Binding(data, "value").bind_ft(elt, name="label_name")
# Verify it works when active
data.value = "first update"
assert elt.children[0] == "first update"
# Deactivate
binding.deactivate()
# Change data - element should NOT update
data.value = "second update"
assert elt.children[0] == "first update"
def test_multiple_bindings_can_coexist(data):
"""
Multiple bindings can be created and managed independently.
"""
elt1 = Label("hello", id="label_id_1")
elt2 = Input(value="world", id="input_id_2")
binding1 = Binding(data, "value").bind_ft(elt1, name="label_name")
binding2 = Binding(data, "value").bind_ft(elt2, name="input_name", attr="value")
assert len(BindingsManager.bindings) == 2
assert binding1._is_active is True
assert binding2._is_active is True
# Change data - both should update
data.value = "updated"
assert elt1.children[0] == "updated"
assert elt2.attrs["value"] == "updated"
# Deactivate one
binding1.deactivate()
assert len(BindingsManager.bindings) == 1
# Change data - only binding2 should update
data.value = "final"
assert elt1.children[0] == "updated" # Not changed
assert elt2.attrs["value"] == "final" # Changed
def test_i_cannot_bind_when_htmx_post_already_set(data):
elt = Input(name="input_elt", hx_post="/some/url")
binding = Binding(data, "value")
with pytest.raises(ValueError, match="htmx post already set on input"):
binding.bind_ft(elt, name="label_name")