Several tests are failing

[mingodad]

Describe the bug
When building with make check several tests fail

To Reproduce
Steps to reproduce the behavior:

1. mkdir build; cd build; cmake -DENABLE_CHECK=On ..; make check
2. See the errors

Obs: I've added two print on check_spec.y:

            if 'grammar' in spec:
                cmd.extend(['--grammar-str', spec['grammar']])
            elif 'grammar_file' in spec:
                if spec['grammar_file'].startswith('/'):
                    cmd.extend(['--grammar-file', spec['grammar_file']])
                else:
                    cmd.extend(['--grammar-file', os.path.dirname(os.path.abspath(specs_file)) + '/' + spec['grammar_file']])
            else:
                raise ValueError('Missing grammar/grammar_file')
            print(cmd) #<<<< here
            print(test['I'].encode('utf-8')) #<<<< here
            proc = subprocess.run(
                cmd,
                capture_output=True,
                input=test['I'].encode('utf-8'),
            )

make check
[  3%] Built target unity
[  6%] Built target peppa
[ 11%] Built target test_flags
[ 15%] Built target cli
[ 20%] Built target test_example_dot
[ 25%] Built target test_example_calc
[ 30%] Built target test_example_json
[ 35%] Built target test_peg
[ 40%] Built target test_positive
[ 45%] Built target test_literal
[ 50%] Built target test_range
[ 55%] Built target test_misc
[ 60%] Built target test_cut
[ 65%] Built target test_sequence
[ 70%] Built target test_choice
[ 75%] Built target test_reference
[ 80%] Built target test_negative
[ 85%] Built target test_example_mustache
[ 90%] Built target test_repeat
[ 95%] Built target test_left_recursion
[100%] Built target test_back_reference
Test project PeppaPEG/build/tests
      Start  1: test_literal
 1/48 Test  #1: test_literal .....................   Passed    0.00 sec
      Start  2: test_range
 2/48 Test  #2: test_range .......................   Passed    0.00 sec
      Start  3: test_sequence
 3/48 Test  #3: test_sequence ....................   Passed    0.00 sec
      Start  4: test_choice
 4/48 Test  #4: test_choice ......................   Passed    0.00 sec
      Start  5: test_reference
 5/48 Test  #5: test_reference ...................   Passed    0.00 sec
      Start  6: test_positive
 6/48 Test  #6: test_positive ....................   Passed    0.00 sec
      Start  7: test_negative
 7/48 Test  #7: test_negative ....................   Passed    0.00 sec
      Start  8: test_repeat
 8/48 Test  #8: test_repeat ......................   Passed    0.00 sec
      Start  9: test_flags
 9/48 Test  #9: test_flags .......................   Passed    0.00 sec
      Start 10: test_cut
10/48 Test #10: test_cut .........................   Passed    0.00 sec
      Start 11: test_back_reference
11/48 Test #11: test_back_reference ..............   Passed    0.00 sec
      Start 12: test_left_recursion
12/48 Test #12: test_left_recursion ..............   Passed    0.00 sec
      Start 13: test_misc
13/48 Test #13: test_misc ........................   Passed    0.00 sec
      Start 14: test_peg
14/48 Test #14: test_peg .........................   Passed    0.01 sec
      Start 15: test_example_mustache
15/48 Test #15: test_example_mustache ............   Passed    0.00 sec
      Start 16: test_example_json
16/48 Test #16: test_example_json ................   Passed    0.02 sec
      Start 17: test_example_calc
17/48 Test #17: test_example_calc ................   Passed    0.01 sec
      Start 18: test_example_dot
18/48 Test #18: test_example_dot .................   Passed    0.08 sec
      Start 19: test_literal_spec.json
19/48 Test #19: test_literal_spec.json ...........***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = "1";']
b'1'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 20: test_range_spec.json
20/48 Test #20: test_range_spec.json .............***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'Num', '--grammar-str', 'Num = [1-9];']
b'1'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 21: test_insensitive_spec.json
21/48 Test #21: test_insensitive_spec.json .......***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = i"1";']
b'1'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 22: test_sequence_spec.json
22/48 Test #22: test_sequence_spec.json ..........***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = "a" "b" "c";']
b'abc'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 23: test_choice_spec.json
23/48 Test #23: test_choice_spec.json ............***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = "a" / "b" / "c";']
b'a'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 24: test_left_recursion_spec.json
24/48 Test #24: test_left_recursion_spec.json ....***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'A', '--grammar-str', 'A = "a" | B "a"; B = "b";']
b'a'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 25: test_lookahead_spec.json
25/48 Test #25: test_lookahead_spec.json .........***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = !"a" [a-f];']
b'b'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 26: test_cut_spec.json
26/48 Test #26: test_cut_spec.json ...............***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = R2*;R2 = "1" ~ "2";']
b'121'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 27: test_repeat_spec.json
27/48 Test #27: test_repeat_spec.json ............***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = ([0-9] / [a-f] / [A-F])+;']
b'1A9F'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 28: test_reference_spec.json
28/48 Test #28: test_reference_spec.json .........***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = R2; R2 = "1";']
b'1'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 29: test_back_reference_spec.yaml
29/48 Test #29: test_back_reference_spec.yaml ....***Failed    0.12 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = R23 \\0;\nR23 = "2" / "3";\n']
b'22'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 30: test_dot_spec.json
30/48 Test #30: test_dot_spec.json ...............***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = .;']
b'\xe5\xa5\xbd'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 31: test_comment_spec.json
31/48 Test #31: test_comment_spec.json ...........***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', 'R1 = "1"# R1 = "3";\n;']
b'1'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 32: test_flags_spec.json
32/48 Test #32: test_flags_spec.json .............***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'R1', '--grammar-str', '@squashed\nR1 = R2 R2;R2 = "X";']
b'XX'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 33: test_peppa_spec.json
33/48 Test #33: test_peppa_spec.json .............***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'number', '--grammar-file', 'PeppaPEG/tests/./peppa.peg']
b'0'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 34: test_golang_v1_17_spec.json
34/48 Test #34: test_golang_v1_17_spec.json ......***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'Literal', '--grammar-file', 'PeppaPEG/tests/../configs/golang-v1.17.peg']
b'42'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 35: toml/test_array.yaml
35/48 Test #35: toml/test_array.yaml .............***Failed    0.22 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'ints = [1, 2, 3, ]\nfloats = [1.1, 2.1, 3.1]\nstrings = ["a", "b", "c"]\ndates = [\n  1987-07-05T17:45:00Z,\n  1979-05-27T07:32:00Z,\n  2006-06-01T11:00:00Z,\n]\ncomments = [\n         1,\n         2, #this is ok\n]\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 36: toml/test_bool.yaml
36/48 Test #36: toml/test_bool.yaml ..............***Failed    0.11 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b't = true\nf = false\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 37: toml/test_comment.yaml
37/48 Test #37: toml/test_comment.yaml ...........***Failed    0.16 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'# This is a full-line comment\nkey = "value" # This is a comment at the end of a line\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 38: toml/test_control.yaml
38/48 Test #38: toml/test_control.yaml ...........***Failed    0.12 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'comment-lf = "ctrl-P" # \x10\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 39: toml/test_datetime.yaml
39/48 Test #39: toml/test_datetime.yaml ..........***Failed    0.21 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'space = 1987-07-05 17:45:00Z\nlower = 1987-07-05t17:45:00z\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 40: toml/test_float.yaml
40/48 Test #40: toml/test_float.yaml .............***Failed    0.17 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'double-point-1 = 0..1\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 41: toml/test_inline_table.yaml
41/48 Test #41: toml/test_inline_table.yaml ......***Failed    0.33 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'people = [{first_name = "Bruce", last_name = "Springsteen"},\n          {first_name = "Eric", last_name = "Clapton"},\n          {first_name = "Bob", last_name = "Seger"}]\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 42: toml/test_integer.yaml
42/48 Test #42: toml/test_integer.yaml ...........***Failed    0.17 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'capital-bin = 0B0\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 43: toml/test_key.yaml
43/48 Test #43: toml/test_key.yaml ...............***Failed    0.27 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'[[agencies]] owner = "S Cjelli"\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 44: toml/test_string.yaml
44/48 Test #44: toml/test_string.yaml ............***Failed    0.24 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'naughty = "\\xAg"\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 45: toml/test_table.yaml
45/48 Test #45: toml/test_table.yaml .............***Failed    0.24 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'toml', '--grammar-file', 'PeppaPEG/tests/toml/../../configs/toml-v1.0.peg']
b'[[]]\nname = "Born to Run"\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 46: abnf/test_rfc5234.yaml
46/48 Test #46: abnf/test_rfc5234.yaml ...........***Failed    0.24 sec
['PeppaPEG/build/cli', 'parse', '--grammar-entry', 'RuleList', '--grammar-file', 'PeppaPEG/tests/abnf/../../configs/abnf.peg']
b'rulelist       =  1*( rule / (*c-wsp c-nl) )\n\nrule           =  rulename defined-as elements c-nl\n                ; continues if next line starts\n                ;  with white space\n\nrulename       =  ALPHA *(ALPHA / DIGIT / "-")\n\ndefined-as     =  *c-wsp ("=" / "=/") *c-wsp\n                                ; basic rules definition and\n                                ;  incremental alternatives\n\nelements       =  alternation *c-wsp\n\nc-wsp          =  WSP / (c-nl WSP)\n\nc-nl           =  comment / CRLF\n                    ; comment or newline\n\ncomment        =  ";" *(WSP / VCHAR) CRLF\n\nalternation    =  concatenation\n                *(*c-wsp "/" *c-wsp concatenation)\n\nconcatenation  =  repetition *(1*c-wsp repetition)\n\nrepetition     =  [repeat] element\n\nrepeat         =  1*DIGIT / (*DIGIT "*" *DIGIT)\n\nelement        =  rulename / group / option /\n                char-val / num-val / prose-val\n\ngroup          =  "(" *c-wsp alternation *c-wsp ")"\n\noption         =  "[" *c-wsp alternation *c-wsp "]"\n\nchar-val       =  DQUOTE *(%x20-21 / %x23-7E) DQUOTE\n                    ; quoted string of SP and VCHAR\n                    ;  without DQUOTE\n\nnum-val        =  "%" (bin-val / dec-val / hex-val)\n\nbin-val        =  "b" 1*BIT\n                [ 1*("." 1*BIT) / ("-" 1*BIT) ]\n                    ; series of concatenated bit values\n                    ;  or single ONEOF range\n\ndec-val        =  "d" 1*DIGIT\n                [ 1*("." 1*DIGIT) / ("-" 1*DIGIT) ]\n\nhex-val        =  "x" 1*HEXDIG\n                [ 1*("." 1*HEXDIG) / ("-" 1*HEXDIG) ]\n\nprose-val      =  "<" *(%x20-3D / %x3F-7E) ">"\n                    ; bracketed string of SP and VCHAR\n                    ;  without angles\n                    ; prose description, to be used as\n                    ;  last resort\n'
Traceback (most recent call last):
  File "PeppaPEG/scripts/check_spec.py", line 87, in <module>
    test_spec()
  File "PeppaPEG/scripts/check_spec.py", line 48, in test_spec
    input=test['I'].encode('utf-8'),
  File "/usr/lib/python3.6/subprocess.py", line 423, in run
    with Popen(*popenargs, **kwargs) as process:
TypeError: __init__() got an unexpected keyword argument 'capture_output'

      Start 47: lua-5.4.3/*.lua
47/48 Test #47: lua-5.4.3/*.lua ..................   Passed    2.31 sec
      Start 48: abnf/*.abnf
48/48 Test #48: abnf/*.abnf ......................   Passed    0.05 sec

42% tests passed, 28 tests failed out of 48

Total Test time (real) =   6.75 sec

The following tests FAILED:
	 19 - test_literal_spec.json (Failed)
	 20 - test_range_spec.json (Failed)
	 21 - test_insensitive_spec.json (Failed)
	 22 - test_sequence_spec.json (Failed)
	 23 - test_choice_spec.json (Failed)
	 24 - test_left_recursion_spec.json (Failed)
	 25 - test_lookahead_spec.json (Failed)
	 26 - test_cut_spec.json (Failed)
	 27 - test_repeat_spec.json (Failed)
	 28 - test_reference_spec.json (Failed)
	 29 - test_back_reference_spec.yaml (Failed)
	 30 - test_dot_spec.json (Failed)
	 31 - test_comment_spec.json (Failed)
	 32 - test_flags_spec.json (Failed)
	 33 - test_peppa_spec.json (Failed)
	 34 - test_golang_v1_17_spec.json (Failed)
	 35 - toml/test_array.yaml (Failed)
	 36 - toml/test_bool.yaml (Failed)
	 37 - toml/test_comment.yaml (Failed)
	 38 - toml/test_control.yaml (Failed)
	 39 - toml/test_datetime.yaml (Failed)
	 40 - toml/test_float.yaml (Failed)
	 41 - toml/test_inline_table.yaml (Failed)
	 42 - toml/test_integer.yaml (Failed)
	 43 - toml/test_key.yaml (Failed)
	 44 - toml/test_string.yaml (Failed)
	 45 - toml/test_table.yaml (Failed)
	 46 - abnf/test_rfc5234.yaml (Failed)
Errors while running CTest
tests/CMakeFiles/check.dir/build.make:94: recipe for target 'tests/CMakeFiles/check' failed
make[3]: *** [tests/CMakeFiles/check] Error 8
CMakeFiles/Makefile2:309: recipe for target 'tests/CMakeFiles/check.dir/all' failed
make[2]: *** [tests/CMakeFiles/check.dir/all] Error 2
CMakeFiles/Makefile2:316: recipe for target 'tests/CMakeFiles/check.dir/rule' failed
make[1]: *** [tests/CMakeFiles/check.dir/rule] Error 2
Makefile:248: recipe for target 'check' failed
make: *** [check] Error 2

[soasme]

capture_output is only available since Python 3.7+. https://docs.python.org/3/library/subprocess.html
It seems the Python version is 3.6 on your local.

[soasme]

Can you please try with the HEAD of main branch? I've checked in a fix, see PR #148.

[mingodad]

Thank you !
All tests pass now on my machine.