1	#!/usr/bin/env bash
2
3	# NOTE on bash bug: After setting IFS to array, it never splits anymore? Even
4	# if you assign IFS again.
5
6	#### IFS is scoped
7	IFS=b
8	word=abcd
9	f() { local IFS=c; argv.py $word; }
10	f
11	argv.py $word
12	## stdout-json: "['ab', 'd']\n['a', 'cd']\n"
13
14	#### Tilde sub is not split, but var sub is
15	HOME="foo bar"
16	argv.py ~
17	argv.py $HOME
18	## stdout-json: "['foo bar']\n['foo', 'bar']\n"
19
20	#### Word splitting
21	a="1 2"
22	b="3 4"
23	argv.py $a"$b"
24	## stdout-json: "['1', '23 4']\n"
25
26	#### Word splitting 2
27	a="1 2"
28	b="3 4"
29	c="5 6"
30	d="7 8"
31	argv.py $a"$b"$c"$d"
32	## stdout-json: "['1', '23 45', '67 8']\n"
33
34	# Has tests on differences between $* "$*" $@ "$@"
35	# http://stackoverflow.com/questions/448407/bash-script-to-receive-and-repass-quoted-parameters
36
37	#### $*
38	func() { argv.py -$*-; }
39	func "a 1" "b 2" "c 3"
40	## stdout: ['-a', '1', 'b', '2', 'c', '3-']
41
42	#### "$*"
43	func() { argv.py "-$*-"; }
44	func "a 1" "b 2" "c 3"
45	## stdout: ['-a 1 b 2 c 3-']
46
47	#### $@
48	# How does this differ from $* ? I don't think it does.
49	func() { argv.py -$@-; }
50	func "a 1" "b 2" "c 3"
51	## stdout: ['-a', '1', 'b', '2', 'c', '3-']
52
53	#### "$@"
54	func() { argv.py "-$@-"; }
55	func "a 1" "b 2" "c 3"
56	## stdout: ['-a 1', 'b 2', 'c 3-']
57
58	#### empty argv
59	argv.py 1 "$@" 2 $@ 3 "$*" 4 $* 5
60	## stdout: ['1', '2', '3', '', '4', '5']
61
62	#### Word elision with space
63	s1=' '
64	argv.py $s1
65	## stdout: []
66
67	#### Word elision with non-whitespace IFS
68	# Treated differently than the default IFS. What is the rule here?
69	IFS='_'
70	char='_'
71	space=' '
72	empty=''
73	argv.py $char
74	argv.py $space
75	argv.py $empty
76	## STDOUT:
77	['']
78	[' ']
79	[]
80	## END
81
82	#### Leading/trailing word elision with non-whitespace IFS
83	# This behavior is weird.
84	IFS=_
85	s1='_a_b_'
86	argv.py $s1
87	## stdout: ['', 'a', 'b']
88
89	#### Leading ' ' vs leading ' _ '
90	# This behavior is weird, but all shells agree.
91	IFS='_ '
92	s1='_ a b _ '
93	s2=' a b _ '
94	argv.py $s1
95	argv.py $s2
96	## STDOUT:
97	['', 'a', 'b']
98	['a', 'b']
99	## END
100
101	#### Multiple non-whitespace IFS chars.
102	IFS=_-
103	s1='a__b---c_d'
104	argv.py $s1
105	## stdout: ['a', '', 'b', '', '', 'c', 'd']
106
107	#### IFS with whitespace and non-whitepace.
108	# NOTE: Three delimiters means two empty words in the middle. No elision.
109	IFS='_ '
110	s1='a_b _ _ _ c _d e'
111	argv.py $s1
112	## stdout: ['a', 'b', '', '', 'c', 'd', 'e']
113
114	#### empty $@ and $* is elided
115	func() { argv.py 1 $@ $* 2; }
116	func
117	## stdout: ['1', '2']
118
119	#### unquoted empty arg is elided
120	empty=""
121	argv.py 1 $empty 2
122	## stdout: ['1', '2']
123
124	#### unquoted whitespace arg is elided
125	space=" "
126	argv.py 1 $space 2
127	## stdout: ['1', '2']
128
129	#### empty literals are not elided
130	space=" "
131	argv.py 1 $space"" 2
132	## stdout: ['1', '', '2']
133
134	#### no splitting when IFS is empty
135	IFS=""
136	foo="a b"
137	argv.py $foo
138	## stdout: ['a b']
139
140	#### default value can yield multiple words
141	argv.py 1 ${undefined:-"2 3" "4 5"} 6
142	## stdout: ['1', '2 3', '4 5', '6']
143
144	#### default value can yield multiple words with part joining
145	argv.py 1${undefined:-"2 3" "4 5"}6
146	## stdout: ['12 3', '4 56']
147
148	#### default value with unquoted IFS char
149	IFS=_
150	argv.py 1${undefined:-"2_3"x_x"4_5"}6
151	## stdout: ['12_3x', 'x4_56']
152
153	#### IFS empty doesn't do splitting
154	IFS=''
155	x=$(echo -e ' a b\tc\n')
156	argv.py $x
157	## STDOUT:
158	[' a b\tc']
159	## END
160	## N-I dash STDOUT:
161	['-e a b\tc']
162	## END
163
164
165	#### IFS unset behaves like $' \t\n'
166	unset IFS
167	x=$(echo -e ' a b\tc\n')
168	argv.py $x
169	## STDOUT:
170	['a', 'b', 'c']
171	## END
172	## N-I dash STDOUT:
173	['-e', 'a', 'b', 'c']
174	## END
175
176	#### IFS='\'
177	# NOTE: OSH fails this because of double backslash escaping issue!
178	IFS='\'
179	s='a\b'
180	argv.py $s
181	## STDOUT:
182	['a', 'b']
183	## END
184
185	#### IFS='\ '
186	# NOTE: OSH fails this because of double backslash escaping issue!
187	# When IFS is \, then you're no longer using backslash escaping.
188	IFS='\ '
189	s='a\b \\ c d\'
190	argv.py $s
191	## STDOUT:
192	['a', 'b', '', 'c', 'd']
193	## END
194
195	#### IFS characters are glob metacharacters
196	IFS='* '
197	s='a*b c'
198	argv.py $s
199
200	IFS='?'
201	s='?x?y?z?'
202	argv.py $s
203
204	IFS='['
205	s='[x[y[z['
206	argv.py $s
207	## STDOUT:
208	['a', 'b', 'c']
209	['', 'x', 'y', 'z']
210	['', 'x', 'y', 'z']
211	## END
212
213	#### Trailing space
214	argv.py 'Xec ho '
215	argv.py X'ec ho '
216	argv.py X"ec ho "
217	## STDOUT:
218	['Xec ho ']
219	['Xec ho ']
220	['Xec ho ']
221	## END
222
223
224	# TODO:
225	# - unquoted args of whitespace are not elided (when IFS = null)
226	# - empty quoted args are kept
227	# - Test ${@:1} and so forth?
228	#
229	# - $* $@ with empty IFS
230	# - $* $@ with custom IFS
231	#
232	# - no splitting when IFS is empty
233	# - word splitting removes leading and trailing whitespace
234
235	# TODO: test framework needs common setup
236
237	# Test IFS and $@ $* on all these
238	#### TODO
239	empty=""
240	space=" "
241	AB="A B"
242	X="X"
243	Yspaces=" Y "
244
245