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import numpy as np
import pytest
from magi_compiler.tokenflow.sampler import exponential_aligned_sampler


def test_sm_sampling():
    result = exponential_aligned_sampler(min_val=8, max_val=132, num_samples=5, align=8)
    assert isinstance(result, list), "返回值必须是列表"
    assert len(result) == 5, f"返回长度应为5，实际为{len(result)}"
    assert all(isinstance(x, int) for x in result), "所有元素必须是整数"
    assert all(x % 8 == 0 for x in result), "所有元素必须对齐到8的倍数"
    assert result[0] == 8, f"首元素应为8，实际为{result[0]}"
    assert result[-1] == 128, f"尾元素应为128（132对齐后），实际为{result[-1]}"
    assert all(result[i] < result[i + 1] for i in range(len(result) - 1)), "采样结果应严格递增"

    mid_value = (8 + 128) / 2
    mid_value_found = np.median(result)
    assert mid_value_found < mid_value, "中间值应小于范围中点，符合指数分布特性"


def test_seqlen_sampling():
    result = exponential_aligned_sampler(min_val=1, max_val=65536, num_samples=5, align=32)
    assert len(result) == 5
    assert all(x % 32 == 0 for x in result)
    assert result[0] == 32
    assert result[-1] == 65536

    mid_value = (32 + 65536) / 2
    mid_value_found = np.median(result)
    assert mid_value_found < mid_value, "中间值应小于范围中点，符合指数分布特性"


def test_min_max_aligned_exactly():
    result = exponential_aligned_sampler(min_val=16, max_val=64, num_samples=4, align=16)
    assert len(result) == 4
    assert result[0] == 16
    assert result[-1] == 64
    assert all(x in [16, 32, 48, 64] for x in result)


def test_output_len_2():
    result = exponential_aligned_sampler(min_val=8, max_val=132, num_samples=2, align=8)
    assert len(result) == 2
    assert result == [8, 128]


def test_large_range_sampling():
    result = exponential_aligned_sampler(min_val=1, max_val=1000001, num_samples=10, align=64)
    assert len(result) == 10
    assert all(x % 64 == 0 for x in result)
    assert result[0] == 64
    assert result[-1] == 1000000


def test_large_output_len():
    with pytest.raises(ValueError) as excinfo:
        result = exponential_aligned_sampler(min_val=8, max_val=64, num_samples=10, align=8)
    assert excinfo is not None