Fix histogram

Author: Евгений Блинов

microbenchmark/__main__.py

@@ -3,13 +3,10 @@
 import importlib
 import sys
 from pathlib import Path
-from typing import Union
 
 from microbenchmark.scenario import Scenario
 from microbenchmark.scenario_group import ScenarioGroup
 
-_Target = Union[Scenario, ScenarioGroup]
-
 
 def main(argv: list[str] | None = None) -> None:
     args = argv if argv is not None else sys.argv[1:]

microbenchmark/_render.py

@@ -98,7 +98,12 @@ def histogram_bounds(durations: Sequence[float]) -> tuple[float, float]:
 
     Args:
         durations: Sequence of per-call timings in seconds.
+
+    Raises:
+        ValueError: If *durations* is empty.
     """
+    if not durations:
+        raise ValueError('durations must not be empty')
     sorted_durs = sorted(durations)
     lo = sorted_durs[0]
     p99_idx = min(len(sorted_durs) - 1, int(len(sorted_durs) * 0.99))

microbenchmark/scenario.py

@@ -68,9 +68,7 @@ def _call_once(self) -> None:
     def run(self, warmup: int = 0) -> BenchmarkResult:
         timer = self._timer
         for _ in range(max(warmup, 0)):
-            timer()
             self._call_once()
-            timer()
         durations: list[float] = []
         loop_start = timer()
         for _ in range(self.number):
@@ -160,7 +158,8 @@ def _fn_call_str(function: object, arguments: Arguments | None) -> str:
 
 def _render_result(result: BenchmarkResult) -> list[str]:
     scenario = result.scenario
-    assert scenario is not None
+    if scenario is None:
+        raise ValueError('BenchmarkResult.scenario must not be None for rendering')
     call_str = _fn_call_str(scenario.function, scenario._arguments)
     label_width = len('p95 mean:')
     lines: list[str] = []

tests/units/test_render.py

@@ -6,6 +6,8 @@
 import sys
 import textwrap
 
+import pytest
+
 from microbenchmark._render import (
     draw_box,
     draw_histogram,
@@ -292,6 +294,11 @@ def test_histogram_bounds_single_value():
     assert lo == hi == 0.005
 
 
+def test_histogram_bounds_empty_raises():
+    with pytest.raises(ValueError, match='empty'):
+        histogram_bounds([])
+
+
 # ---------------------------------------------------------------------------
 # draw_histogram_axis
 # ---------------------------------------------------------------------------

tests/units/test_scenario.py

@@ -9,7 +9,7 @@
 from sigmatch import SignatureMismatchError
 
 from microbenchmark import BenchmarkResult, Scenario, ScenarioGroup, arguments
-from microbenchmark.scenario import _fn_call_str
+from microbenchmark.scenario import _fn_call_str, _render_result
 
 # ---------------------------------------------------------------------------
 # Construction
@@ -354,7 +354,7 @@ def fake_timer() -> float:
     scenario = Scenario(lambda: None, name='s', number=3, timer=fake_timer)
     result = scenario.run(warmup=2)
 
-    assert tick[0] == 12  # warmup: 2*2=4, loop_start: 1, run: 3*2=6, loop_end: 1 → 12
+    assert tick[0] == 8  # loop_start: 1, run: 3*2=6, loop_end: 1 → 8 (warmup has no timer calls)
     assert len(result.durations) == 3
     assert result.durations == pytest.approx((1.0, 1.0, 1.0))
 
@@ -603,3 +603,9 @@ def test_fn_call_str_non_oserror_propagates():
 
     with pytest.raises(ValueError, match='unexpected'), patch('microbenchmark.scenario.superrepr', side_effect=ValueError('unexpected')):
         _fn_call_str(fn, None)
+
+
+def test_render_result_raises_when_scenario_is_none():
+    result = BenchmarkResult.from_json('{"durations":[0.001,0.002],"is_primary":true,"scenario":null}')
+    with pytest.raises(ValueError, match='scenario must not be None'):
+        _render_result(result)