Function _inject_or_diag

Scripts/codegen/generate_ue_components.py:233–258

Inject ``body`` between the ``CODEGEN_ `` markers in ``text``. When the markers are missing AND the body is non-empty, fire a diagnostic that names the host kind (e.g. 'subclass header'), the path, the tag, and what didn't land. Returns (new_text, ok). This collapses ~12 near-id

(
    text: str,
    tag: str,
    body: str,
    *,
    host_path: str,
    host_kind: str,
    block_label: str,
    diag_source: str,
)

def _inject_or_diag(
    text: str,
    tag: str,
    body: str,
    *,
    host_path: str,
    host_kind: str,
    block_label: str,
    diag_source: str,
) -> Tuple[str, bool]:
    """Inject ``body`` between the ``CODEGEN_<tag>`` markers in ``text``.
    When the markers are missing AND the body is non-empty, fire a
    diagnostic that names the host kind (e.g. 'subclass header'), the
    path, the tag, and what didn&#x27;t land. Returns (new_text, ok).

    This collapses ~12 near-identical try-inject-then-diag stanzas
    that used to live in the emit_*_class_injection callers."""
    new_text, ok = inject_between_tags(text, tag, body, balance_source=diag_source)
    if not ok and body.strip():
        _diag_add(
            f"[diagnostic] {host_kind} '{host_path}' is missing the "
            f"CODEGEN_{tag}_START/END marker pair; {block_label} was "
            f"NOT injected.",
            source=diag_source,
        )
    return new_text, ok


def _guarded_export(toggle: str, body: str,