출생증명서를 단 복사본

HEADER_MARK = "GENERATED FROM the-kit"

# One deploy mechanism, every language in the family. The header has
# to be a COMMENT in the target language or the file will not parse.
COMMENT_STYLES = {
    ".py":    ("# ", ""),
    ".ts":    ("// ", ""),
    ".tsx":   ("// ", ""),
    ".js":    ("// ", ""),
    ".css":   ("/* ", " */"),   # CSS needs a closing delimiter
    ".swift": ("// ", ""),
}


def header_for(source_rel: str, target: Path, sha: str) -> str:
    prefix, suffix = COMMENT_STYLES.get(target.suffix, ("# ", ""))
    return (
        f"{prefix}{HEADER_MARK}/{source_rel} @ {sha} - DO NOT EDIT HERE. "
        f"Edit the kit and run the sync script.{suffix}\n"
    )


def strip_header(text: str) -> str:
    """Remove the provenance line before comparing bodies.

    Guarded on the MARKER, not on 'is line 1 a comment'. A kit file may
    legitimately open with a comment of its own; only a line carrying
    the marker is ours to drop.
    """
    lines = text.splitlines(keepends=True)
    if lines and HEADER_MARK in lines[0]:
        return "".join(lines[1:])
    return text


# Deploy: header + body. Compare: body only.
expected_body = source_text
expected_file = header_for(source_rel, target, kit_sha) + expected_body

actual = target.read_text()
is_drifted = strip_header(actual) != expected_body      # <- the body

# The header question is only meaningful INSIDE the body-matches arm.
# Asked on its own it is true whenever `is_drifted` is true, so it
# would not be cosmetic at all - it would just be drift, reported
# twice under two names.
needs_refresh = (not is_drifted) and actual != expected_file
#
# Two DIFFERENT questions, and the nesting is what keeps them apart.
# `is_drifted` fails a test suite. `needs_refresh` is cosmetic, and
# is only acted on when a deploy explicitly asks for it.