1	#!/bin/bash
2	#
3	# Tests for pipelines.
4	# NOTE: Grammatically, ! is part of the pipeline:
5	#
6	# pipeline : pipe_sequence
7	# | Bang pipe_sequence
8
9	### Brace group in pipeline
10	{ echo one; echo two; } | tac
11	# stdout-json: "two\none\n"
12
13	### For loop in pipeline
14	for w in one two; do
15	echo $w
16	done | tac
17	# stdout-json: "two\none\n"
18
19	### Redirect in Pipeline
20	echo hi 1>&2 | wc -l
21	# stdout: 0
22	# BUG zsh stdout: 1
23
24	### Exit code is last status
25	echo a | egrep '[0-9]+'
26	# status: 1
27
28	### PIPESTATUS
29	{ sleep 0.03; exit 1; } | { sleep 0.02; exit 2; } | { sleep 0.01; exit 3; }
30	echo ${PIPESTATUS[@]}
31	# stdout: 1 2 3
32	# N-I dash status: 2
33	# N-I zsh status: 3
34	# N-I dash/zsh stdout-json: ""
35
36	### |&
37	stdout_stderr.py |& cat
38	# stdout-json: "STDERR\nSTDOUT\n"
39	# status: 0
40	# N-I dash/mksh stdout-json: ""
41	# N-I dash status: 2
42
43	### ! turns non-zero into zero
44	! $SH -c 'exit 42'; echo $?
45	# stdout: 0
46	# status: 0
47
48	### ! turns zero into 1
49	! $SH -c 'exit 0'; echo $?
50	# stdout: 1
51	# status: 0
52
53	### ! in if
54	if ! echo hi; then
55	echo TRUE
56	else
57	echo FALSE
58	fi
59	# stdout-json: "hi\nFALSE\n"
60	# status: 0
61
62	### ! with ||
63	! echo hi || echo FAILED
64	# stdout-json: "hi\nFAILED\n"
65	# status: 0
66
67	### ! with { }
68	! { echo 1; echo 2; } || echo FAILED
69	# stdout-json: "1\n2\nFAILED\n"
70	# status: 0
71
72	### ! with ( )
73	! ( echo 1; echo 2 ) || echo FAILED
74	# stdout-json: "1\n2\nFAILED\n"
75	# status: 0
76
77	### ! is not a command
78	v='!'
79	$v echo hi
80	# status: 127
81
82	### Evaluation of argv[0] in pipeline occurs in child
83	${cmd=echo} hi | wc -l
84	echo "cmd=$cmd"
85	# stdout-json: "1\ncmd=\n"
86	# BUG zsh stdout-json: "1\ncmd=echo\n"