Source code for tracmass.seagrid.debug

"""Debugging utilities for tracmass.seagrid."""

import functools
import linecache
import sys




def trace_lines(func):
    """Decorator that prints each source line of *func* as it executes.

    Sub-function calls are not traced — only the lines of the decorated
    function itself are printed.

    Examples
    --------
    >>> @trace_lines
    ... def open_dataset(...):
    ...     ...
    """
    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        def local_trace(frame, event, arg):
            if event == "line":
                src = linecache.getline(
                    frame.f_code.co_filename, frame.f_lineno
                ).rstrip()
                print(f"  {frame.f_lineno}: {src}")
            return local_trace if event != "call" else None

        def global_trace(frame, event, arg):
            if event == "call" and frame.f_code is func.__code__:
                return local_trace
            return None

        old = sys.gettrace()
        sys.settrace(global_trace)
        try:
            return func(*args, **kwargs)
        finally:
            sys.settrace(old)

    return wrapper