Class FormattedExcinfo

src/_pytest/_code/code.py:684–960

Presenting information about failing Functions and Generators.

@attr.s(auto_attribs=True)
class FormattedExcinfo:
    """Presenting information about failing Functions and Generators."""

    # for traceback entries
    flow_marker: ClassVar = ">"
    fail_marker: ClassVar = "E"

    showlocals: bool = False
    style: "_TracebackStyle" = "long"
    abspath: bool = True
    tbfilter: bool = True
    funcargs: bool = False
    truncate_locals: bool = True
    chain: bool = True
    astcache: Dict[Union[str, Path], ast.AST] = attr.ib(
        factory=dict, init=False, repr=False
    )

    def _getindent(self, source: "Source") -> int:
        # Figure out indent for the given source.
        try:
            s = str(source.getstatement(len(source) - 1))
        except KeyboardInterrupt:
            raise
        except BaseException:
            try:
                s = str(source[-1])
            except KeyboardInterrupt:
                raise
            except BaseException:
                return 0
        return 4 + (len(s) - len(s.lstrip()))

    def _getentrysource(self, entry: TracebackEntry) -> Optional["Source"]:
        source = entry.getsource(self.astcache)
        if source is not None:
            source = source.deindent()
        return source

    def repr_args(self, entry: TracebackEntry) -> Optional["ReprFuncArgs"]:
        if self.funcargs:
            args = []
            for argname, argvalue in entry.frame.getargs(var=True):
                args.append((argname, saferepr(argvalue)))
            return ReprFuncArgs(args)
        return None

    def get_source(
        self,
        source: Optional["Source"],
        line_index: int = -1,
        excinfo: Optional[ExceptionInfo[BaseException]] = None,
        short: bool = False,
    ) -> List[str]:
        """Return formatted and marked up source lines."""
        lines = []
        if source is None or line_index >= len(source.lines):
            source = Source("???")