pint.mcmc_fitter.CompositeMCMCFitter is broken

[abhisrkckl]

This class is a Fitter for dealing with multiple sets of TOAs at the same time with a single model (according to the docstring). I get an exception when I try to instantiate it.

This class is not covered by any tests. That's why this error went unnoticed thus far.

from pint.models import get_model_and_toas
from pint.config import examplefile
from pint.mcmc_fitter import CompositeMCMCFitter, lnlikelihood_chi2
from pint.sampler import EmceeSampler

m, t = get_model_and_toas(parfile, timfile)
ftr = CompositeMCMCFitter([t], m, sampler, [lnlikelihood_chi2])

Error:

TypeError                                 Traceback (most recent call last)
Cell In[19], line 1
----> 1 ftr = CompositeMCMCFitter([t], m, sampler, [lnlikelihood_chi2])

File ~/miniconda3/envs/pint-devel/lib/python3.10/site-packages/pint_pulsar-0.9.2+177.g9741c898-py3.10.egg/pint/mcmc_fitter.py:593, in CompositeMCMCFitter.__init__(self, toas, model, sampler, lnlikes, **kwargs)
    590 self.minMJD = kwargs.get("minMJD", 0)
    591 self.maxMJD = kwargs.get("maxMJD", 100000)
--> 593 self.fitkeys, self.fitvals, self.fiterrs = self.generate_fit_keyvals(
    594     phs, phserr
    595 )
    596 self.n_fit_params = len(self.fitvals)
    598 self.numcalls = 0

TypeError: MCMCFitter.generate_fit_keyvals() takes 1 positional argument but 3 were given