Class BareSnprintfChecker

ci/lint_cpp/bare_snprintf_checker.py:64–120

Bans bare C printf-family calls inside src/ (FastLED #2773 item 1.5).

class BareSnprintfChecker(FileContentChecker):
    """Bans bare C printf-family calls inside src/ (FastLED #2773 item 1.5)."""

    def __init__(self):
        self.violations: dict[str, list[tuple[int, str]]] = {}

    def should_process_file(self, file_path: str) -> bool:
        # Only src/.
        if not file_path.startswith(str(SRC_ROOT)):
            return False
        if not file_path.endswith((".cpp", ".h", ".hpp")):
            return False
        norm = file_path.replace("\\", "/")
        # Skip the shim itself.
        for exempt in EXEMPT_FILES:
            if norm.endswith(exempt):
                return False
        # Skip third-party upstream code — we don't control these sources.
        if "/third_party/" in norm:
            return False
        # Skip host-only unit-test watchdog scaffolding. These files are HOST
        # test infrastructure (apple/posix/win) and never link into ESP32
        # firmware, so the binary-size argument doesn't apply.
        if norm.endswith("/run_unit_test.hpp"):
            return False
        return True

    def check_file_content(self, file_content: FileContent) -> list[str]:
        violations: list[tuple[int, str]] = []
        in_block_comment = False

        for line_number, line in enumerate(file_content.lines, 1):
            stripped = line.strip()

            # Track /* ... */ blocks (single-line case handled by the slice below).
            if in_block_comment:
                if "*/" in line:
                    in_block_comment = False
                continue
            if "/*" in line and "*/" not in line:
                in_block_comment = True
                continue

            if stripped.startswith("//"):
                continue
            if _SUPPRESS in line:
                continue

            # Strip trailing // comment so we don't match inside a comment.
            code = line.split("//")[0]
            if _BANNED_PATTERN.search(code):
                violations.append((line_number, line.rstrip()))

        if violations:
            self.violations[file_content.path] = violations

        return []