External Issue: chpldoc doesn't format a 1-tuple correctly

16940, “cassella”, “chpldoc doesn’t format a 1-tuple correctly”, “2021-01-13T03:40:50Z”

Steps to Reproduce

Source Code:

proc tuple1Default(arg=(x,));
proc tuple2Default(arg=(x,y));
proc tuple3Default(arg=(x,y,z));

Compile command:

chpldoc --no-html --save-sphinx docs foo.chpl

cat docs/source/modules/foo.rst

.. function:: proc tuple1Default(arg = (x))

.. function:: proc tuple2Default(arg = (x, y))

.. function:: proc tuple3Default(arg = (x, y, z))

The first one should be (x,), not (x).

Associated Future Test(s):

Configuration Information

chpl version 1.24.0 pre-release (5f95c6d1d0)

gcc (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0

CHPL_TARGET_PLATFORM: linux64
CHPL_TARGET_COMPILER: gnu
CHPL_TARGET_ARCH: x86_64
CHPL_TARGET_CPU: native *
CHPL_LOCALE_MODEL: flat
CHPL_COMM: gasnet *
  CHPL_COMM_SUBSTRATE: udp
  CHPL_GASNET_SEGMENT: everything
CHPL_TASKS: qthreads
CHPL_LAUNCHER: amudprun
CHPL_TIMERS: generic
CHPL_UNWIND: none
CHPL_MEM: jemalloc
CHPL_ATOMICS: cstdlib
  CHPL_NETWORK_ATOMICS: none
CHPL_GMP: none
CHPL_HWLOC: bundled
CHPL_REGEXP: re2
CHPL_LLVM: none
CHPL_AUX_FILESYS: none