1	#!/usr/bin/env bash
2
3	#### case
4	foo=a; case $foo in [0-9]) echo number;; [a-z]) echo letter;; esac
5	## stdout: letter
6
7	#### case in subshell
8	# Hm this subhell has to know about the closing ) and stuff like that.
9	# case_clause is a compound_command, which is a command. And a subshell
10	# takes a compound_list, which is a list of terms, which has and_ors in them
11	# ... which eventually boils down to a command.
12	echo $(foo=a; case $foo in [0-9]) echo number;; [a-z]) echo letter;; esac)
13	## stdout: letter
14
15	#### Command sub word part
16	# "The token shall not be delimited by the end of the substitution."
17	foo=FOO; echo $(echo $foo)bar$(echo $foo)
18	## stdout: FOObarFOO
19
20	#### Backtick
21	foo=FOO; echo `echo $foo`bar`echo $foo`
22	## stdout: FOObarFOO
23
24	#### Backtick 2
25	echo `echo -n l; echo -n s`
26	## stdout: ls
27
28	#### Nested backticks
29	# Inner `` are escaped! # Not sure how to do triple.. Seems like an unlikely
30	# use case. Not sure if I even want to support this!
31	echo X > $TMP/000000-first
32	echo `\`echo -n l; echo -n s\` $TMP | grep 000000-first`
33	## stdout: 000000-first
34
35	#### Making command out of command sub should work
36	# Works in bash and dash!
37	$(echo ec)$(echo ho) split builtin
38	## stdout: split builtin
39
40	#### Making keyword out of command sub should NOT work
41	# This doesn't work in bash or dash! Hm builtins are different than keywords /
42	# reserved words I guess.
43	# dash fails, but gives code 0
44	$(echo f)$(echo or) i in a b c; do echo $i; done
45	echo status=$?
46	## stdout-json: ""
47	## status: 2
48	## BUG dash stdout-json: "\nstatus=0\n"
49	## BUG dash status: 0
50	## OK mksh status: 1
51
52	#### Command sub with here doc
53	echo $(<<EOF tac
54	one
55	two
56	EOF
57	)
58	## stdout: two one
59
60	#### Here doc with pipeline
61	<<EOF tac | tr '\n' 'X'
62	one
63	two
64	EOF
65	## stdout-json: "twoXoneX"
66
67	#### Command Sub word split
68	argv.py $(echo 'hi there') "$(echo 'hi there')"
69	## stdout: ['hi', 'there', 'hi there']
70
71	#### Command Sub trailing newline removed
72	s=$(python -c 'print "ab\ncd\n"')
73	argv.py "$s"
74	## stdout: ['ab\ncd']
75
76	#### Command Sub trailing whitespace not removed
77	s=$(python -c 'print "ab\ncd\n "')
78	argv.py "$s"
79	## stdout: ['ab\ncd\n ']
80
81	#### Command Sub and exit code
82	# A command resets the exit code, but an assignment doesn't.
83	echo $(echo x; exit 33)
84	echo $?
85	x=$(echo x; exit 33)
86	echo $?
87	## STDOUT:
88	x
89	0
90	33
91	## END
92
93	#### Command Sub in local sets exit code
94	# A command resets the exit code, but an assignment doesn't.
95	f() {
96	echo $(echo x; exit 33)
97	echo $?
98	local x=$(echo x; exit 33)
99	echo $?
100	}
101	f
102	## STDOUT:
103	x
104	0
105	0
106	## END