add optional parameter suppress_indent to method Design.write_scadnano_file #170
Description
On a large (~3000 strand) scadnano design, writing out a json/scadnano file becomes extremely slow as a result of _SuppressableIndentEncoder (assuming suppress_indent=True), taking up the vast majority of the time, and increasing the time to create the json string from around 1 second to over 20 seconds. For example:
5086971 function calls (4773439 primitive calls) in 21.794 seconds
Ordered by: internal time
ncalls tottime percall cumtime percall filename:lineno(function)
23838 20.359 0.001 20.359 0.001 {method 'replace' of 'str' objects}
1 0.197 0.197 20.866 20.866 scadnano.py:141(encode)
1062464 0.164 0.000 0.554 0.000 scadnano.py:4141(<genexpr>)
1825253 0.152 0.000 0.242 0.000 {built-in method builtins.isinstance}
16600 0.149 0.000 0.153 0.000 scadnano.py:1474(to_json_serializable)
201088 0.144 0.000 0.320 0.000 scadnano.py:2922(<listcomp>)
64 0.089 0.001 0.643 0.010 {built-in method builtins.max}
201088 0.070 0.000 0.390 0.000 scadnano.py:2920(bound_domains)
215316/119964 0.064 0.000 0.298 0.000 encoder.py:413(_iterencode)
23839 0.050 0.000 0.050 0.000 encoder.py:204(iterencode)
330260 0.048 0.000 0.048 0.000 {built-in method _abc._abc_instancecheck}
170638/119948 0.045 0.000 0.262 0.000 encoder.py:277(_iterencode_list)
239778/119964 0.045 0.000 0.279 0.000 encoder.py:333(_iterencode_dict)
330260 0.043 0.000 0.090 0.000 abc.py:96(__instancecheck__)
23839/1 0.031 0.000 0.311 0.311 encoder.py:182(encode)