Class Source

src/_pytest/_code/source.py:17–111

An immutable object holding a source code fragment. When using Source(...), the source lines are deindented.

class Source:
    """An immutable object holding a source code fragment.

    When using Source(...), the source lines are deindented.
    """

    def __init__(self, obj: object = None) -> None:
        if not obj:
            self.lines: List[str] = []
        elif isinstance(obj, Source):
            self.lines = obj.lines
        elif isinstance(obj, (tuple, list)):
            self.lines = deindent(x.rstrip("\n") for x in obj)
        elif isinstance(obj, str):
            self.lines = deindent(obj.split("\n"))
        else:
            try:
                rawcode = getrawcode(obj)
                src = inspect.getsource(rawcode)
            except TypeError:
                src = inspect.getsource(obj)  # type: ignore[arg-type]
            self.lines = deindent(src.split("\n"))

    def __eq__(self, other: object) -> bool:
        if not isinstance(other, Source):
            return NotImplemented
        return self.lines == other.lines

    # Ignore type because of https://github.com/python/mypy/issues/4266.
    __hash__ = None  # type: ignore

    @overload
    def __getitem__(self, key: int) -> str:
        ...

    @overload
    def __getitem__(self, key: slice) -> "Source":
        ...

    def __getitem__(self, key: Union[int, slice]) -> Union[str, "Source"]:
        if isinstance(key, int):
            return self.lines[key]
        else:
            if key.step not in (None, 1):
                raise IndexError("cannot slice a Source with a step")
            newsource = Source()
            newsource.lines = self.lines[key.start : key.stop]
            return newsource

    def __iter__(self) -> Iterator[str]:
        return iter(self.lines)

    def __len__(self) -> int:
        return len(self.lines)

    def strip(self) -> "Source":
        """Return new Source object with trailing and leading blank lines removed."""
        start, end = 0, len(self)