Nicers error message while running `bake` command with an empty `Bakefile`

[rednafi]

Currently, if I run bake command when the Bakefile is empty, the error message seems very scary:

Traceback (most recent call last):
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/bin/bake", line 8, in <module>
    sys.exit(entrypoint())
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/click/core.py", line 764, in __call__
    return self.main(*args, **kwargs)
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/click/core.py", line 717, in main
    rv = self.invoke(ctx)
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/click/core.py", line 956, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/click/core.py", line 555, in invoke
    return callback(*args, **kwargs)
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/cli.py", line 297, in entrypoint
    for _task in bf.tasks:
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 217, in tasks
    return self.tasks
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 217, in tasks
    return self.tasks
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 217, in tasks
    return self.tasks
  [Previous line repeated 974 more times]
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 212, in tasks
    for i, chunk in enumerate(self.chunks):
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 105, in chunks
    self._chunks = [c for c in self._iter_chunks()]
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 105, in <listcomp>
    self._chunks = [c for c in self._iter_chunks()]
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 65, in _iter_chunks
    all_chunks = [tl for tl in self._iter_chunk_task_lines()]
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 65, in <listcomp>
    all_chunks = [tl for tl in self._iter_chunk_task_lines()]
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 90, in _iter_chunk_task_lines
    for i, line in enumerate(self.source_lines):
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 166, in source_lines
    return self.source.split("\n")
  File "/home/redowan/.local/share/virtualenvs/flask-template-wBuRwttx/lib/python3.7/site-packages/bake/bakefile.py", line 162, in source
    return f.read()
RecursionError: maximum recursion depth exceeded while calling a Python object

Can we make this something nicer?