string concat speed tests

#!/usr/bin/env python

''' Speed tests of string concatenation with `+` vs `str.join()`

    Written by PM 2Ring 2015.10.01
'''

from __future__ import print_function

import sys
from timeit import Timer

def concat_plus(lst):
    s = ''
    for u in lst:
        s += u
    return s

def concat_plus_i(lst):
    s = ''
    for i in range(len(lst)):
        s += lst[i]
    return s

def concat_join(lst):
    s = []
    for u in lst:
        s.append(u)
    return ''.join(s)

def concat_join_i(lst):
    s = []
    for i in range(len(lst)):
        s.append(lst[i])
    return ''.join(s)

def concat_join_lc(lst):
    return ''.join([u for u in lst])

def concat_join_list(lst):
    return ''.join(lst)

funcs = (
    concat_join_i,
    concat_join,
    concat_plus_i,
    concat_plus,
    concat_join_lc,
    concat_join_list,
)

def verify(lst):
    print('Verifying...')

    results = []
    for func in funcs:
        fname = func.func_name
        print('%s' % fname)
        s = func(lst)
        #print(s)
        results.append(s)

    s = results[0]
    if all(s==u for u in results):
        print('\nAll strings are equal\n')
    else:
        print('\nString mismatch error! Aborting.')
        exit()

def time_test(loops, reps):
    ''' Print timing stats for all the functions '''
    for func in funcs:
        fname = func.func_name
        print('\n%s' % fname)
        setup = 'from __main__ import lst, ' + fname
        cmd = fname + '(lst)'
        t = Timer(cmd, setup)
        r = t.repeat(reps, loops)
        r.sort()
        print(r)


if __name__ == "__main__":
    lo = int(sys.argv[1]) if len(sys.argv) > 1 else 2
    step = int(sys.argv[2]) if len(sys.argv) > 2 else 1
    base = sys.argv[3] if len(sys.argv) > 3 else 'abc'
    mult = int(sys.argv[4]) if len(sys.argv) > 4 else 1

    hi = lo + 5*step
    print('High string count = %d' % hi)

    base *= mult
    print('Base string length = %d' % len(base))

    all_strings = [base + str(i) for i in xrange(hi)]

    verify(all_strings)

    loops, reps = 100, 5
    print('Timing tests\nLoops = %d, Repetitions = %d' % (loops, reps))

    for i in xrange(lo, hi + step, step):
        lst = all_strings[:i]
        print('\n*** %2d strings ***' % i)
        time_test(loops, reps)