init: company-haness 설계

benchmark/fixtures/GT-01/paginate.py

@@ -0,0 +1,13 @@
+"""Pagination helper — contains an off-by-one bug that drops the last item of a page.
+
+The bug: `end = start + size - 1` and slicing `items[start:end]` excludes the last
+element of each page. A correct implementation returns exactly `size` items per page
+(and the remainder on the final page).
+"""
+
+
+def paginate(items, page, size):
+    """Return the `page`-th (1-indexed) slice of `items` with `size` per page."""
+    start = (page - 1) * size
+    end = start + size - 1  # BUG: off-by-one — drops the last item of the page
+    return items[start:end]

benchmark/fixtures/GT-01/test_paginate.py

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+"""Objective acceptance test for GT-01 (held as the verify command).
+
+This test currently FAILS against the buggy paginate() (off-by-one drops the last
+item). A correct fix makes it pass. The benchmark runner runs `pytest -q` after each
+arm and grades first-pass-acceptance on the exit code.
+"""
+from paginate import paginate
+
+
+def test_full_page_returns_size_items():
+    items = list(range(10))
+    assert paginate(items, 1, 5) == [0, 1, 2, 3, 4]
+    assert paginate(items, 2, 5) == [5, 6, 7, 8, 9]
+
+
+def test_last_item_not_dropped():
+    assert paginate([1, 2, 3], 1, 3) == [1, 2, 3]
+
+
+def test_partial_last_page():
+    assert paginate([1, 2, 3, 4, 5], 1, 2) == [1, 2]
+    assert paginate([1, 2, 3, 4, 5], 3, 2) == [5]

benchmark/fixtures/GT-R2/stats.py

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+"""Running statistics — contains a bug in `median` for even-length inputs.
+
+The bug: for an even number of elements, `median` returns the lower-middle element
+instead of the average of the two middle elements. `mean` is correct.
+"""
+
+
+def mean(xs):
+    return sum(xs) / len(xs)
+
+
+def median(xs):
+    s = sorted(xs)
+    n = len(s)
+    mid = n // 2
+    return s[mid]  # BUG: even-length should average s[mid-1] and s[mid]

benchmark/fixtures/GT-R2/test_stats.py

@@ -0,0 +1,14 @@
+from stats import mean, median
+
+
+def test_mean():
+    assert mean([2, 4, 6]) == 4
+
+
+def test_median_odd():
+    assert median([3, 1, 2]) == 2
+
+
+def test_median_even():
+    assert median([1, 2, 3, 4]) == 2.5   # average of the two middle elements
+    assert median([10, 20]) == 15