mechanical-refactor-verify

1import subprocess2import sys3from pathlib import Path4 5import pytest6 7sys.path.insert(0, str(Path(__file__).resolve().parents[2]))8 9import mechanical_refactor_reproduction_utils as rr10from mechanical_refactor_reproduction_utils import (11    Repro,12    _def_span,13    _find_class,14    _find_def,15    _replace_span,16    _slice_span,17    dedent,18    exec_command,19    git_add_and_commit,20    verify_mechanical_refactor,21)22from reproduction_testlib import _apply, _commit, _git, _write  # noqa: F40123 24# --- extract_function ----------------------------------------------------------25 26 27def test_extract_function_relocates_body_and_replaces_with_call(tmp_path: Path) -> None:28    """An inline block is cut verbatim, re-indented under the new signature, and the call site29    replaced; the body lands at function-body indent."""30    (tmp_path / "src.py").write_text(31        "class Q:\n"32        "    def run(self, n):\n"33        "        total = 0\n"34        "        for i in range(n):\n"35        "            total += i * i\n"36        "        return total\n"37    )38    (tmp_path / "dst.py").write_text("def existing():\n    return 0\n")39    body = "        total = 0\n        for i in range(n):\n            total += i * i\n"40    r = Repro("b", "t").extract_function(41        "src.py",42        "dst.py",43        name="sum_squares",44        signature="def sum_squares(n):",45        body=body,46        body_indent=8,47        call="        total = sum_squares(n)\n",48        return_text="    return total\n",49    )50    _apply(r, tmp_path)51    src_out = (tmp_path / "src.py").read_text()52    assert "        total = sum_squares(n)\n" in src_out53    assert "for i in range(n)" not in src_out54    assert (55        "def sum_squares(n):\n"56        "    total = 0\n"57        "    for i in range(n):\n"58        "        total += i * i\n"59        "    return total\n"60    ) in (tmp_path / "dst.py").read_text()61 62 63def test_extract_function_inserts_before_named_sibling(tmp_path: Path) -> None:64    """With before=, the new function lands immediately above that sibling at module level."""65    (tmp_path / "src.py").write_text("x = compute()\n")66    (tmp_path / "dst.py").write_text(67        "def a():\n    return 1\n\n\ndef c():\n    return 3\n"68    )69    r = Repro("b", "t").extract_function(70        "src.py",71        "dst.py",72        name="b",73        signature="def b():",74        body="x = compute()\n",75        body_indent=0,76        call="x = b()\n",77        return_text="    return x\n",78        before="c",79    )80    _apply(r, tmp_path)81    dst_out = (tmp_path / "dst.py").read_text()82    assert dst_out.index("def a") < dst_out.index("def b") < dst_out.index("def c")83    assert "x = b()\n" == (tmp_path / "src.py").read_text()84 85 86def test_extract_function_asserts_block_not_unique(tmp_path: Path) -> None:87    """A block that occurs more than once in the source raises, so the cut is unambiguous."""88    (tmp_path / "src.py").write_text("p = f()\np = f()\n")89    (tmp_path / "dst.py").write_text("def z():\n    return 0\n")90    r = Repro("b", "t").extract_function(91        "src.py",92        "dst.py",93        name="g",94        signature="def g():",95        body="p = f()\n",96        body_indent=0,97        call="p = g()\n",98    )99    with pytest.raises(AssertionError):100        _apply(r, tmp_path)101 102 103# --- adversarial audit: module extraction ----------------------------------------104 105 106# --- adversarial audit: extract_function -----------------------------------------107 108 109def test_extract_function_does_not_pad_blank_lines_in_the_body(tmp_path: Path) -> None:110    """Interior blank lines of the extracted body stay bare newlines, unpadded."""111    (tmp_path / "src.py").write_text("        a = 1\n\n        b = 2\n")112    (tmp_path / "dst.py").write_text("def z():\n    return 0\n")113    r = Repro("b", "t").extract_function(114        "src.py",115        "dst.py",116        name="g",117        signature="def g():",118        body="        a = 1\n\n        b = 2\n",119        body_indent=8,120        call="        g()\n",121    )122    _apply(r, tmp_path)123    assert (tmp_path / "src.py").read_text() == "        g()\n"124    assert (tmp_path / "dst.py").read_text() == (125        "def z():\n    return 0\n\ndef g():\n    a = 1\n\n    b = 2\n"126    )127 128 129def test_extract_function_does_not_reindent_string_literal_interiors(130    tmp_path: Path,131) -> None:132    """Triple-quoted string interior lines keep their exact bytes through the extraction."""133    (tmp_path / "src.py").write_text(134        "TEMPLATE = '''\nliteral line\n'''\nx = TEMPLATE\n"135    )136    (tmp_path / "dst.py").write_text("def existing():\n    return 0\n")137    r = Repro("b", "t").extract_function(138        "src.py",139        "dst.py",140        name="make",141        signature="def make():",142        body="TEMPLATE = '''\nliteral line\n'''\nx = TEMPLATE\n",143        body_indent=0,144        call="x = make()\n",145        return_text="    return x\n",146    )147    _apply(r, tmp_path)148    assert "\nliteral line\n" in (tmp_path / "dst.py").read_text()149 150 151def test_extract_function_rejects_a_mid_line_substring_match(tmp_path: Path) -> None:152    """A body that only matches mid-line must fail loudly instead of splicing the call."""153    (tmp_path / "src.py").write_text("value = prefix_total = 0\n")154    (tmp_path / "dst.py").write_text("def z():\n    return 0\n")155    r = Repro("b", "t").extract_function(156        "src.py",157        "dst.py",158        name="g",159        signature="def g():",160        body="total = 0\n",161        body_indent=0,162        call="total = g()\n",163    )164    with pytest.raises(AssertionError):165        _apply(r, tmp_path)166 167 168def test_extract_function_into_class_indents_body_to_method_depth(169    tmp_path: Path,170) -> None:171    """Extracting into a class must indent the relocated body to method depth."""172    (tmp_path / "src.py").write_text("val = compute_thing()\n")173    (tmp_path / "dst.py").write_text(174        "class H:\n    def last(self):\n        return 0\n"175    )176    r = Repro("b", "t").extract_function(177        "src.py",178        "dst.py",179        name="helper",180        signature="    def helper(self):",181        body="val = compute_thing()\n",182        body_indent=0,183        call="val = h.helper()\n",184        return_text="        return val\n",185        into_class="H",186    )187    _apply(r, tmp_path)188    out = (tmp_path / "dst.py").read_text()189    compile(out, "dst.py", "exec")190    assert "    def helper(self):\n        val = compute_thing()\n" in out191