⚡️ Speed up method UIElementRegistry.get_object by 5%

[codeflash-ai]

📄 5% (0.05x) speedup for UIElementRegistry.get_object in marimo/_plugins/ui/_core/registry.py

⏱️ Runtime : 565 microseconds → 537 microseconds (best of 104 runs)

📝 Explanation and details

The optimization replaces a containment check followed by dictionary access with a try/except pattern, eliminating one dictionary lookup operation.

Key changes:

• Eliminated redundant dictionary lookup: The original code performed object_id not in self._objects (first lookup) followed by self._objects[object_id]() (second lookup). The optimized version uses try: ref = self._objects[object_id] with except KeyError: to handle missing keys, reducing this to a single dictionary access.

Why this is faster:

• Single hash table operation: Dictionary lookups in Python involve computing a hash and searching the hash table. The original approach required this expensive operation twice for each call, while the optimized version only does it once.
• EAFP (Easier to Ask for Forgiveness than Permission): Python's try/except is optimized for the common case where exceptions don't occur. Since missing UIElement IDs are likely rare in normal operation, the exception handling overhead is minimal compared to the saved dictionary lookup.

Performance characteristics from tests:

• Best for frequent successful lookups: Shows 3-17% improvements in tests with existing objects (test_get_object_large_number_of_objects, test_get_object_performance_with_many_lookups)
• Slight overhead for error cases: 20-23% slower when KeyError is raised, but this is acceptable since error cases should be infrequent in production
• Scales well: The optimization becomes more beneficial with larger registries and repeated access patterns

The 5% overall speedup comes from eliminating the redundant hash table lookup that occurred on every successful get_object call.

✅ Correctness verification report:

Test	Status
⚙️ Existing Unit Tests	🔘 None Found
🌀 Generated Regression Tests	✅ 2557 Passed
⏪ Replay Tests	🔘 None Found
🔎 Concolic Coverage Tests	✅ 2 Passed
📊 Tests Coverage	100.0%

🌀 Generated Regression Tests and Runtime

import weakref

# imports
import pytest
from marimo._plugins.ui._core.registry import UIElementRegistry

# --- Minimal stubs to allow tests to run independently ---

class UIElement:
    """A minimal UIElement stub for testing."""
    def __init__(self, value):
        self.value = value

# For test purposes, we treat UIElementId as a string and CellId_t as an int
UIElementId = str
CellId_t = int
from marimo._plugins.ui._core.registry import UIElementRegistry

# --- Unit tests ---

# -------------------------------
# 1. Basic Test Cases
# -------------------------------

def test_get_object_returns_correct_object():
    """Test that get_object returns the correct UIElement instance."""
    registry = UIElementRegistry()
    elem = UIElement("foo")
    registry._objects["id1"] = weakref.ref(elem)
    codeflash_output = registry.get_object("id1"); result = codeflash_output # 703ns -> 747ns (5.89% slower)

def test_get_object_multiple_objects():
    """Test that get_object works for multiple different objects."""
    registry = UIElementRegistry()
    elem1 = UIElement("a")
    elem2 = UIElement("b")
    registry._objects["idA"] = weakref.ref(elem1)
    registry._objects["idB"] = weakref.ref(elem2)
    codeflash_output = registry.get_object("idA") # 640ns -> 681ns (6.02% slower)
    codeflash_output = registry.get_object("idB") # 240ns -> 257ns (6.61% slower)

def test_get_object_with_integer_id():
    """Test that get_object works with non-string IDs (if allowed)."""
    registry = UIElementRegistry()
    elem = UIElement("bar")
    # Using integer as UIElementId
    registry._objects[123] = weakref.ref(elem)
    codeflash_output = registry.get_object(123) # 650ns -> 639ns (1.72% faster)

# -------------------------------
# 2. Edge Test Cases
# -------------------------------

def test_get_object_id_not_found():
    """Test that get_object raises KeyError if the id is not present."""
    registry = UIElementRegistry()
    with pytest.raises(KeyError):
        registry.get_object("missing_id") # 1.09μs -> 1.36μs (20.1% slower)

def test_get_object_id_found_but_object_garbage_collected():
    """
    Test that get_object raises AssertionError if the weakref is dead.
    """
    registry = UIElementRegistry()
    elem = UIElement("temp")
    registry._objects["dead_id"] = weakref.ref(elem)
    # Delete the only strong reference to elem
    del elem
    import gc; gc.collect()
    with pytest.raises(AssertionError):
        registry.get_object("dead_id") # 2.20μs -> 2.10μs (4.52% faster)

def test_get_object_with_empty_string_id():
    """Test get_object with an empty string as ID."""
    registry = UIElementRegistry()
    elem = UIElement("empty")
    registry._objects[""] = weakref.ref(elem)
    codeflash_output = registry.get_object("") # 788ns -> 858ns (8.16% slower)

def test_get_object_with_special_characters_id():
    """Test get_object with special characters in the ID."""
    registry = UIElementRegistry()
    elem = UIElement("special")
    special_id = "!@#$%^&*()_+-=[]{}|;':,./<>?"
    registry._objects[special_id] = weakref.ref(elem)
    codeflash_output = registry.get_object(special_id) # 634ns -> 732ns (13.4% slower)

def test_get_object_with_none_id():
    """Test get_object with None as ID (should raise KeyError)."""
    registry = UIElementRegistry()
    with pytest.raises(KeyError):
        registry.get_object(None) # 1.22μs -> 1.54μs (21.1% slower)

def test_get_object_with_object_id_type():
    """Test get_object with a non-hashable object as ID (should raise TypeError)."""
    registry = UIElementRegistry()
    class Dummy: pass
    dummy = Dummy()
    with pytest.raises(TypeError):
        registry.get_object(dummy)

# -------------------------------
# 3. Large Scale Test Cases
# -------------------------------

def test_get_object_large_number_of_elements():
    """Test get_object performance and correctness with many elements."""
    registry = UIElementRegistry()
    elements = []
    for i in range(1000):
        elem = UIElement(i)
        registry._objects[f"id{i}"] = weakref.ref(elem)
        elements.append(elem)
    # Check a few random elements
    for idx in [0, 499, 999]:
        codeflash_output = registry.get_object(f"id{idx}"); obj = codeflash_output # 1.79μs -> 1.56μs (14.9% faster)

def test_get_object_after_bulk_deletion():
    """Test get_object after many objects have been deleted and garbage collected."""
    registry = UIElementRegistry()
    for i in range(1000):
        elem = UIElement(i)
        registry._objects[f"id{i}"] = weakref.ref(elem)
    # Delete all but one element
    keep_elem = UIElement("keep")
    registry._objects["keep"] = weakref.ref(keep_elem)
    for i in range(1000):
        registry._objects[f"id{i}"] = weakref.ref(UIElement(i))  # new, short-lived
    import gc; gc.collect()
    # Only 'keep' should be alive
    codeflash_output = registry.get_object("keep") # 1.65μs -> 1.48μs (11.4% faster)

def test_get_object_all_ids_are_unique():
    """Test get_object with all unique IDs and ensure no cross-contamination."""
    registry = UIElementRegistry()
    for i in range(1000):
        elem = UIElement(f"val{i}")
        registry._objects[f"unique{i}"] = weakref.ref(elem)
    # Ensure each id returns the correct object
    for i in range(0, 1000, 100):  # sample every 100th
        codeflash_output = registry.get_object(f"unique{i}"); obj = codeflash_output
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
#------------------------------------------------
import weakref

# imports
import pytest
from marimo._plugins.ui._core.registry import UIElementRegistry


# Minimal stubs for dependencies (to avoid external imports)
class UIElement:
    def __init__(self, value):
        self.value = value

# Type aliases for clarity (as per the original code)
CellId_t = int
UIElementId = str
from marimo._plugins.ui._core.registry import UIElementRegistry

# -------------------------
# Unit tests for get_object
# -------------------------

# -------- BASIC TEST CASES --------

def test_get_object_returns_correct_object():
    # Test that get_object returns the correct UIElement instance
    registry = UIElementRegistry()
    elem = UIElement("foo")
    registry._objects["id1"] = weakref.ref(elem)
    codeflash_output = registry.get_object("id1"); result = codeflash_output # 914ns -> 775ns (17.9% faster)

def test_get_object_multiple_objects():
    # Test that get_object works with multiple objects
    registry = UIElementRegistry()
    elem1 = UIElement(1)
    elem2 = UIElement(2)
    registry._objects["id1"] = weakref.ref(elem1)
    registry._objects["id2"] = weakref.ref(elem2)
    codeflash_output = registry.get_object("id1") # 612ns -> 683ns (10.4% slower)
    codeflash_output = registry.get_object("id2") # 232ns -> 223ns (4.04% faster)

def test_get_object_with_different_types_of_ids():
    # Test that get_object works with different string IDs
    registry = UIElementRegistry()
    elem = UIElement("bar")
    for object_id in ["foo", "123", "special!@#", ""]:
        registry._objects[object_id] = weakref.ref(elem)
        codeflash_output = registry.get_object(object_id) # 1.40μs -> 1.21μs (15.9% faster)

# -------- EDGE TEST CASES --------

def test_get_object_nonexistent_id_raises_keyerror():
    # Test that get_object raises KeyError for missing object ID
    registry = UIElementRegistry()
    with pytest.raises(KeyError):
        registry.get_object("does_not_exist") # 995ns -> 1.29μs (22.7% slower)

def test_get_object_when_weakref_is_dead_asserts():
    # Test that get_object asserts if the weakref is dead (object was garbage collected)
    registry = UIElementRegistry()
    object_id = "dead_id"
    elem = UIElement("dead")
    registry._objects[object_id] = weakref.ref(elem)
    # Delete the only strong reference to elem
    del elem
    import gc
    gc.collect()
    # Now the weakref is dead, so get_object should assert
    with pytest.raises(AssertionError):
        registry.get_object(object_id) # 2.12μs -> 2.02μs (4.75% faster)

def test_get_object_with_empty_registry_raises_keyerror():
    # Test that get_object raises KeyError if registry is empty
    registry = UIElementRegistry()
    with pytest.raises(KeyError):
        registry.get_object("any_id") # 1.09μs -> 1.41μs (22.6% slower)

def test_get_object_id_with_none_value_in_objects():
    # Test that get_object asserts if the weakref returns None (should never happen if used correctly)
    registry = UIElementRegistry()
    object_id = "none_id"
    # Simulate a weakref that returns None
    class DummyRef:
        def __call__(self):
            return None
    registry._objects[object_id] = DummyRef()
    with pytest.raises(AssertionError):
        registry.get_object(object_id) # 1.40μs -> 1.44μs (2.64% slower)

def test_get_object_id_with_non_string_id():
    # Test that get_object works with non-string IDs if used (though type hint is str)
    registry = UIElementRegistry()
    elem = UIElement("baz")
    registry._objects[123] = weakref.ref(elem)
    codeflash_output = registry.get_object(123) # 803ns -> 810ns (0.864% slower)

# -------- LARGE SCALE TEST CASES --------

def test_get_object_large_number_of_objects():
    # Test that get_object works efficiently with a large number of objects
    registry = UIElementRegistry()
    num_objects = 1000
    elements = []
    for i in range(num_objects):
        elem = UIElement(i)
        elements.append(elem)
        registry._objects[f"id_{i}"] = weakref.ref(elem)
    # Test random access
    for i in (0, 499, 999):
        codeflash_output = registry.get_object(f"id_{i}"); obj = codeflash_output # 1.59μs -> 1.52μs (4.47% faster)
    # Test all objects
    for i in range(num_objects):
        codeflash_output = registry.get_object(f"id_{i}"); obj = codeflash_output # 206μs -> 190μs (8.34% faster)

def test_get_object_performance_with_many_lookups():
    # Test that repeated lookups do not degrade performance or correctness
    registry = UIElementRegistry()
    elem = UIElement("repeat")
    registry._objects["repeat_id"] = weakref.ref(elem)
    for _ in range(1000):
        codeflash_output = registry.get_object("repeat_id") # 172μs -> 166μs (3.65% faster)

def test_get_object_with_many_dead_weakrefs():
    # Test that get_object still works when many dead weakrefs are present
    registry = UIElementRegistry()
    num_dead = 500
    for i in range(num_dead):
        # Each weakref points to an object that immediately goes out of scope
        registry._objects[f"dead_{i}"] = weakref.ref(UIElement(i))
    # Insert one live object
    live_elem = UIElement("alive")
    registry._objects["live"] = weakref.ref(live_elem)
    # Only the live one should succeed
    codeflash_output = registry.get_object("live") # 739ns -> 720ns (2.64% faster)
    # All dead ones should assert
    for i in range(num_dead):
        with pytest.raises(AssertionError):
            registry.get_object(f"dead_{i}")

def test_get_object_with_large_and_unusual_ids():
    # Test get_object with very long and unusual string IDs
    registry = UIElementRegistry()
    long_id = "x" * 500
    special_id = "!@#$%^&*()_+-=[]{}|;':,.<>/?"
    elem1 = UIElement("long")
    elem2 = UIElement("special")
    registry._objects[long_id] = weakref.ref(elem1)
    registry._objects[special_id] = weakref.ref(elem2)
    codeflash_output = registry.get_object(long_id) # 702ns -> 635ns (10.6% faster)
    codeflash_output = registry.get_object(special_id) # 271ns -> 274ns (1.09% slower)
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
#------------------------------------------------
from marimo._plugins.ui._core.registry import UIElementRegistry
import pytest

def test_UIElementRegistry_get_object():
    with pytest.raises(KeyError, match="'UIElement\\ with\\ id\\ \\ not\\ found'"):
        UIElementRegistry.get_object(UIElementRegistry(), '')

🔎 Concolic Coverage Tests and Runtime

Test File::Test Function	Original ⏱️	Optimized ⏱️	Speedup
codeflash_concolic_298po3xl/tmpodurf15r/test_concolic_coverage.py::test_UIElementRegistry_get_object	949ns	1.28μs	-25.6%⚠️

To edit these changes git checkout codeflash/optimize-UIElementRegistry.get_object-mh67uh16 and push.