1	#!/usr/bin/env 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 starts pipeline
14	for w in one two; do
15	echo $w
16	done | tac
17	## stdout-json: "two\none\n"
18
19	#### While Loop ends pipeline
20	seq 3 | while read i
21	do
22	echo ".$i"
23	done
24	## stdout-json: ".1\n.2\n.3\n"
25
26	#### Redirect in Pipeline
27	echo hi 1>&2 | wc -l
28	## stdout: 0
29	## BUG zsh stdout: 1
30
31	#### Pipeline comments
32	echo abcd | # input
33	# blank line
34	tr a-z A-Z # transform
35	## stdout: ABCD
36
37	#### Exit code is last status
38	echo a | egrep '[0-9]+'
39	## status: 1
40
41	#### PIPESTATUS
42	return3() {
43	return 3
44	}
45	{ sleep 0.03; exit 1; } | { sleep 0.02; exit 2; } | { sleep 0.01; return3; }
46	echo ${PIPESTATUS[@]}
47	## stdout: 1 2 3
48	## N-I dash status: 2
49	## N-I dash stdout-json: ""
50	## N-I zsh status: 0
51	## N-I zsh stdout-json: "\n"
52
53	#### PIPESTATUS with shopt -s lastpipe
54	shopt -s lastpipe
55	return3() {
56	return 3
57	}
58	{ sleep 0.03; exit 1; } | { sleep 0.02; exit 2; } | { sleep 0.01; return3; }
59	echo ${PIPESTATUS[@]}
60	## stdout: 1 2 3
61	## N-I dash status: 2
62	## N-I dash stdout-json: ""
63	## N-I zsh status: 0
64	## N-I zsh stdout-json: "\n"
65
66	#### |&
67	stdout_stderr.py |& cat
68	## stdout-json: "STDERR\nSTDOUT\n"
69	## status: 0
70	## N-I dash/mksh stdout-json: ""
71	## N-I dash status: 2
72
73	#### ! turns non-zero into zero
74	! $SH -c 'exit 42'; echo $?
75	## stdout: 0
76	## status: 0
77
78	#### ! turns zero into 1
79	! $SH -c 'exit 0'; echo $?
80	## stdout: 1
81	## status: 0
82
83	#### ! in if
84	if ! echo hi; then
85	echo TRUE
86	else
87	echo FALSE
88	fi
89	## stdout-json: "hi\nFALSE\n"
90	## status: 0
91
92	#### ! with ||
93	! echo hi || echo FAILED
94	## stdout-json: "hi\nFAILED\n"
95	## status: 0
96
97	#### ! with { }
98	! { echo 1; echo 2; } || echo FAILED
99	## stdout-json: "1\n2\nFAILED\n"
100	## status: 0
101
102	#### ! with ( )
103	! ( echo 1; echo 2 ) || echo FAILED
104	## stdout-json: "1\n2\nFAILED\n"
105	## status: 0
106
107	#### ! is not a command
108	v='!'
109	$v echo hi
110	## status: 127
111
112	#### Evaluation of argv[0] in pipeline occurs in child
113	${cmd=echo} hi | wc -l
114	echo "cmd=$cmd"
115	## STDOUT:
116	1
117	cmd=
118	## END
119	## BUG zsh STDOUT:
120	1
121	cmd=echo
122	## END
123
124	#### bash/dash/mksh run the last command is run in its own process
125	echo hi | read line
126	echo "line=$line"
127	## stdout: line=hi
128	## OK bash/dash/mksh stdout: line=
129
130	#### shopt -s lastpipe (always on in OSH)
131	shopt -s lastpipe
132	echo hi | read line
133	echo "line=$line"
134	## stdout: line=hi
135	## N-I dash/mksh stdout: line=
136
137	#### shopt -s lastpipe (always on in OSH)
138	shopt -s lastpipe
139	i=0
140	seq 3 | while read line; do
141	(( i++ ))
142	done
143	echo i=$i
144	## stdout: i=3
145	## N-I dash/mksh stdout: i=0
146