FabledGrimoire/tests/test_hook_duplicate_confirmation.py

"""The by-name duplicate arm confirms its grep hits against the real extractor.

The extractors that decide what a payload DEFINES blank comment and string
spans before any line matcher runs. This is the other end — `grimoire_local_dups`,
which decides which OTHER files already define that name — and a plain
`git grep` cannot do that.

A grep sees lines, not spans. The line

    class with only modifier rules is a deletion that went half-way.

is prose from a module docstring in this repo, and it matches the arm's pattern
for `name=with`. So the arm would tell a writer their genuine symbol was
already defined, and point at a docstring.

WHAT CONFIRMATION COSTS, measured rather than guessed: it drops string
literals, comments, import statements and Vue's `const emit = defineEmits()`
boilerplate, and no real definition — where a name has both a real definition
and a phantom, the phantom goes and the definition stays. The arm is
dominated by its `git grep` calls, so confirming adds about 15% (a mean of
~30ms) rather than the second a per-(name, file) shape would cost.

These cases are written against real git repositories rather than mocks,
because what is being pinned is the interaction between `git grep`, `head` and
the extractor — which is also where a `pipefail` + `head` interaction lives.
"""
from __future__ import annotations

import os
import shutil
import subprocess
from pathlib import Path

import pytest

ROOT = Path(__file__).resolve().parents[1]
DEFS = ROOT / "plugin" / "hooks" / "grimoire_defs.sh"


@pytest.fixture
def repo(tmp_path):
    """A committed git repo, plus a runner for the arm against it."""
    for tool in ("git", "bash", "awk"):
        if shutil.which(tool) is None:
            pytest.skip(f"{tool!r} not installed")
    env = {"PATH": os.environ["PATH"], "HOME": str(tmp_path),
           "GIT_AUTHOR_NAME": "t", "GIT_AUTHOR_EMAIL": "t@x",
           "GIT_COMMITTER_NAME": "t", "GIT_COMMITTER_EMAIL": "t@x"}
    root = tmp_path / "repo"
    root.mkdir()
    subprocess.run(["git", "init", "-q"], cwd=root, check=True, env=env)

    def build(files: dict[str, str]):
        for rel, text in files.items():
            path = root / rel
            path.parent.mkdir(parents=True, exist_ok=True)
            path.write_text(text)
        subprocess.run(["git", "add", "-A"], cwd=root, check=True, env=env,
                       capture_output=True)
        subprocess.run(["git", "commit", "-q", "-m", "base"], cwd=root,
                       check=True, env=env, capture_output=True)

    def run(names: str, writing: str = "new.py") -> str:
        script = (f'set -uo pipefail\n. "{DEFS}"\n'
                  f'printf %s "$NAMES" | grimoire_local_dups "{root}" {writing}\n')
        out = subprocess.run(["bash", "-c", script], capture_output=True,
                             text=True, env={**env, "NAMES": names}, timeout=120)
        assert out.returncode == 0, out.stderr
        return out.stdout

    return build, run


# ── the case the task names ──────────────────────────────────────────────────


def test_a_sentence_about_a_definition_is_not_a_definition(repo):
    """One real `def change`, one docstring that
    wraps onto a line beginning `function change`. The writer is told about
    the first file and not the second."""
    build, run = repo
    build({
        "real.py": "def change(a, b):\n    return a\n",
        "prose.py": (
            '"""Some module.\n\n'
            'When a caller moves, the enclosing\n'
            'function change may have moved with it, which is the case\n'
            'this paragraph exists to describe.\n'
            '"""\n\n'
            'X = 1\n'
        ),
    })
    out = run("sym\tchange\n")
    assert "real.py" in out
    assert "prose.py" not in out, (
        "a wrapped docstring line still reads as a definition — the "
        "confirmation pass did not run, or did not see the span"
    )
    assert "in 1 other file(s)" in out


def test_the_repos_own_prose_does_not_define_with():
    """Not a fixture — this repo's actual corpus, the realistic case.

    Without the confirmation pass the arm names files for `with` on prose in
    docstrings and comments — `…record type with no vector…`, `A class with
    no rules anywhere…`. With it the arm names none, and none is the correct
    answer: nothing here defines a symbol called
    `with`, and in several of the languages in this tree it could not, because
    it is a keyword.

    Asserting on emptiness is only honest if the assertion could see a hit —
    so it checks the arm ran, via a name that IS defined here.
    """
    if shutil.which("bash") is None:
        pytest.skip("bash not installed")

    def arm(name: str) -> str:
        script = (f'set -uo pipefail\n. "{DEFS}"\n'
                  f'printf "sym\\t{name}\\n" | grimoire_local_dups "{ROOT}" nothing.py\n')
        out = subprocess.run(["bash", "-c", script], capture_output=True,
                             text=True, timeout=180)
        assert out.returncode == 0, out.stderr
        return out.stdout

    assert arm("extract_definitions").strip(), (
        "the arm found nothing for a name this repo certainly defines, so a "
        "silent result below would prove nothing"
    )
    assert arm("with").strip() == "", (
        "`with` is prose in every file that matches the grep — a hit here is "
        "a sentence being read as a definition"
    )


def test_a_name_that_is_both_real_and_phantom_keeps_the_real_file(repo):
    """The narrowing case, and the one that would betray an over-eager filter:
    the phantom file drops out and the genuine definition stays."""
    build, run = repo
    build({
        "lib.py": "def create_note(user_id):\n    return user_id\n",
        "test_form.py": 'canon = shape_form("async def create_note(user_id: int, ...):", "sym")\n',
    })
    out = run("sym\tcreate_note\n")
    assert "lib.py" in out
    assert "test_form.py" not in out
    assert "in 1 other file(s)" in out


def test_an_import_is_not_a_definition(repo):
    """TypeScript's `import { type Foo }` matched the `type\\s+NAME` arm, so a
    new type was reported as a duplicate of the files importing it."""
    build, run = repo
    build({
        "card.vue": 'import {\n  type Choices, type Decision,\n} from "@/api/inception";\n',
        "real.ts": "export type Choices = { a: number };\n",
    })
    out = run("sym\tChoices\n")
    assert "card.vue" not in out, "an import site is not a definition site"


# ── the caps ─────────────────────────────────────────────────────────────────


def test_the_candidate_cap_is_raised_above_the_display_cap():
    """Confirmation REMOVES hits, so a cap applied before it runs lets phantom
    matches crowd real definitions out of the window — hits dropped before
    anyone looked at them. Asserted on structure because the ordering is what
    matters, not the numbers."""
    src = DEFS.read_text()
    for const in ("_GRIMOIRE_DUP_CANDIDATES=", "_GRIMOIRE_DUP_SHOWN="):
        assert const in src, f"{const.rstrip(chr(61))} is gone — the two caps were folded back together"
    cands = int(src.split("_GRIMOIRE_DUP_CANDIDATES=")[1].split("\n")[0])
    shown = int(src.split("_GRIMOIRE_DUP_SHOWN=")[1].split("\n")[0])
    assert cands > shown, (
        f"candidates ({cands}) must exceed the display cap ({shown}), or "
        "confirmation can only ever shrink an already-truncated window"
    )


def test_phantoms_ahead_of_the_display_cap_do_not_hide_a_real_definition(repo):
    """Four phantom files sort before the one real definition. With the old
    `head -4` on the grep, the real file never entered the window at all."""
    build, run = repo
    files = {f"a_phantom_{i}.py": f'BLURB = """\nclass Widget is described here.\n"""\n'
             for i in range(4)}
    files["z_real.py"] = "class Widget:\n    pass\n"
    build(files)
    out = run("sym\tWidget\n")
    assert "z_real.py" in out, "the real definition sorted behind four phantoms"
    assert "a_phantom_0.py" not in out


def test_the_early_exiting_head_still_keeps_its_own_output(repo):
    """Under `pipefail` a `head` that
    exits while git grep is still writing must not void the hits it printed.
    Every file here holds a REAL definition, so confirmation keeps them all
    and only the display cap applies."""
    build, run = repo
    build({f"module_with_a_fairly_long_descriptive_name_{i}.py": "def slug(t):\n    return t\n"
           for i in range(3000)})
    out = run("sym\tslug\n")
    assert "`slug` is already defined in 4 other file(s)" in out


# ── css ──────────────────────────────────────────────────────────────────────


def test_a_selector_named_inside_a_css_comment_is_not_a_rule(repo):
    """A selector inside a CSS comment, on the lookup side rather than the
    extraction side."""
    build, run = repo
    build({
        "real.css": ".badge { color: red; }\n",
        # The selector must START the line, or the old anchored pattern
        # never matched it and this case would pass without the fix.
        "notes.css": "/*\n.badge, .chip and friends were retired here\n*/\na { color: blue; }\n",
    })
    out = run("css\tbadge\n")
    assert "real.css" in out
    assert "notes.css" not in out