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	{ sleep 0.03; exit 1; } | { sleep 0.02; exit 2; } | { sleep 0.01; exit 3; }
43	echo ${PIPESTATUS[@]}
44	## stdout: 1 2 3
45	## N-I dash status: 2
46	## N-I zsh status: 3
47	## N-I dash/zsh stdout-json: ""
48
49	#### |&
50	stdout_stderr.py |& cat
51	## stdout-json: "STDERR\nSTDOUT\n"
52	## status: 0
53	## N-I dash/mksh stdout-json: ""
54	## N-I dash status: 2
55
56	#### ! turns non-zero into zero
57	! $SH -c 'exit 42'; echo $?
58	## stdout: 0
59	## status: 0
60
61	#### ! turns zero into 1
62	! $SH -c 'exit 0'; echo $?
63	## stdout: 1
64	## status: 0
65
66	#### ! in if
67	if ! echo hi; then
68	echo TRUE
69	else
70	echo FALSE
71	fi
72	## stdout-json: "hi\nFALSE\n"
73	## status: 0
74
75	#### ! with ||
76	! echo hi || echo FAILED
77	## stdout-json: "hi\nFAILED\n"
78	## status: 0
79
80	#### ! with { }
81	! { echo 1; echo 2; } || echo FAILED
82	## stdout-json: "1\n2\nFAILED\n"
83	## status: 0
84
85	#### ! with ( )
86	! ( echo 1; echo 2 ) || echo FAILED
87	## stdout-json: "1\n2\nFAILED\n"
88	## status: 0
89
90	#### ! is not a command
91	v='!'
92	$v echo hi
93	## status: 127
94
95	#### Evaluation of argv[0] in pipeline occurs in child
96	${cmd=echo} hi | wc -l
97	echo "cmd=$cmd"
98	## stdout-json: "1\ncmd=\n"
99	## BUG zsh stdout-json: "1\ncmd=echo\n"
100
101	#### last command is run in its own process
102	echo hi | read line
103	echo "line=$line"
104	## stdout: line=
105	## OK zsh stdout: line=hi
106
107	#### shopt -s lastpipe
108	shopt -s lastpipe
109	echo hi | read line
110	echo "line=$line"
111	## stdout: line=hi
112	## N-I dash/mksh stdout: line=
113
114	#### shopt -s lastpipe
115	shopt -s lastpipe
116	i=0
117	seq 3 | while read line; do
118	(( i++ ))
119	done
120	echo i=$i
121	## stdout: i=3
122	## N-I dash/mksh stdout: i=0
123