xref: /freebsd/contrib/bmake/unit-tests/varmod-assign.mk (revision 6a7405f5a6b639682cacf01e35d561411ff556aa)
1# $NetBSD: varmod-assign.mk,v 1.25 2024/08/29 20:20:36 rillig Exp $
2#
3# Tests for the obscure ::= variable modifiers, which perform variable
4# assignments during evaluation, just like the = operator in C.
5
6.if !make(target)
7
8all:	mod-assign-empty-{1,2,3}
9all:	mod-assign-parse-{1,2,3}
10all:	mod-assign-shell-error
11
12# In the following loop expression,
13# the '::?=' modifier applies the assignment operator '?=' 3 times. The
14# operator '?=' only has an effect for the first time, therefore the variable
15# FIRST ends up with the value 1.
16.if "${1 2 3:L:@i@${FIRST::?=$i}@} first=${FIRST}" != " first=1"
17.  error
18.endif
19
20# In the following loop expression,
21# the modifier '::=' applies the assignment operator '=' 3 times. The
22# operator '=' overwrites the previous value, therefore the variable LAST ends
23# up with the value 3.
24.if "${1 2 3:L:@i@${LAST::=$i}@} last=${LAST}" != " last=3"
25.  error
26.endif
27
28# In the following loop expression,
29# the modifier '::+=' applies the assignment operator '+=' 3 times. The
30# operator '+=' appends 3 times to the variable, therefore the variable
31# APPENDED ends up with the value "1 2 3".
32.if "${1 2 3:L:@i@${APPENDED::+=$i}@} appended=${APPENDED}" != " appended=1 2 3"
33.  error
34.endif
35
36# In the following loop expression,
37# the modifier '::!=' applies the assignment operator '!=' 3 times. Just as
38# with the modifier '::=', the last value is stored in the RAN variable.
39.if "${1 2 3:L:@i@${RAN::!=${i:%=echo '<%>';}}@} ran=${RAN}" != " ran=<3>"
40.  error
41.endif
42
43# When a '::=' modifier is evaluated as part of an .if condition, it happens
44# in the command line scope.
45.if "${FIRST}, ${LAST}, ${APPENDED}, ${RAN}" != "1, 3, 1 2 3, <3>"
46.  error
47.endif
48
49# Tests for nested assignments, which are hard to read and therefore seldom
50# used in practice.
51
52# The condition "1" is true, therefore THEN1 gets assigned a value,
53# and the inner IT1 as well.  Nothing surprising here.
54.if "${1:?${THEN1::=then1${IT1::=t1}}:${ELSE1::=else1${IE1::=e1}}} ${THEN1}${ELSE1}${IT1}${IE1}" != " then1t1"
55.  error
56.endif
57
58# The condition "0" is false, therefore ELSE2 gets assigned a value,
59# and the inner IE2 as well.  Nothing surprising here as well.
60.if "${0:?${THEN2::=then2${IT2::=t2}}:${ELSE2::=else2${IE2::=e2}}} ${THEN2}${ELSE2}${IT2}${IE2}" != " else2e2"
61.  error
62.endif
63
64# The same effects happen when the variables are defined elsewhere.
65SINK3:=	${1:?${THEN3::=then3${IT3::=t3}}:${ELSE3::=else3${IE3::=e3}}} ${THEN3}${ELSE3}${IT3}${IE3}
66SINK4:=	${0:?${THEN4::=then4${IT4::=t4}}:${ELSE4::=else4${IE4::=e4}}} ${THEN4}${ELSE4}${IT4}${IE4}
67.if ${SINK3} != " then3t3"
68.  error
69.endif
70.if ${SINK4} != " else4e4"
71.  error
72.endif
73
74mod-assign-empty-1:
75	# Assigning to the empty variable would obviously not work since that
76	# variable is write-protected.
77# expect: make: Bad modifier ":"
78	@echo $@: ${::=value}
79
80mod-assign-empty-2:
81	# In this variant, it is not as obvious that the name of the
82	# expression is empty.
83# expect: make: Bad modifier ":"
84	@echo $@: ${:Uvalue::=overwritten}
85
86mod-assign-empty-3:
87	# The :L modifier sets the value of the expression to its variable
88	# name.  The name of the expression is "VAR", therefore assigning to
89	# that variable works.
90# expect: mod-assign-empty-3: VAR=overwritten
91	@echo $@: ${VAR:L::=overwritten} VAR=${VAR}
92
93mod-assign-parse-1:
94	# The modifier for assignment operators starts with a ':'.
95	# An 'x' after that is an invalid modifier.
96# expect: make: Unknown modifier ":x"
97	@echo ${ASSIGN::x}
98
99mod-assign-parse-2:
100	# When parsing an assignment operator fails because the operator is
101	# incomplete, make falls back to the SysV modifier.
102	@echo ${SYSV::=sysv\:x}${SYSV::x=:y}
103
104mod-assign-parse-3:
105# expect: make: Unfinished modifier ('}' missing)
106	@echo ${ASSIGN::=value	# missing closing brace
107
108mod-assign-shell-error:
109	# If the command succeeds, the variable is assigned.
110	@${SH_OK::!= echo word; true } echo ok=${SH_OK}
111
112	# If the command fails, the variable keeps its previous value.
113	@${SH_ERR::=previous}
114	@${SH_ERR::!= echo word; (exit 13) } echo err=${SH_ERR}
115
116# XXX: The ::= modifier expands its right-hand side exactly once.
117# This differs subtly from normal assignments such as '+=' or '=', which copy
118# their right-hand side literally.
119APPEND.prev=		previous
120APPEND.var=		${APPEND.prev}
121APPEND.indirect=	indirect $${:Unot expanded}
122APPEND.dollar=		$${APPEND.indirect}
123.if ${APPEND.var::+=${APPEND.dollar}} != ""
124.  error
125.endif
126.if ${APPEND.var} != "previous indirect \${:Unot expanded}"
127.  error
128.endif
129
130
131# The assignment modifier can be used in an expression that is
132# enclosed in parentheses.  In such a case, parsing stops at the first ')',
133# not at the first '}'.
134VAR=	previous
135_:=	$(VAR::=current})
136.if ${VAR} != "current}"
137.  error
138.endif
139
140
141# Before var.c 1.888 from 2021-03-15, an expression using the modifier '::='
142# expanded its variable name once too often during evaluation.  This was only
143# relevant for variable names containing a '$' sign in their actual name, not
144# the usual VAR.${param}.
145.MAKEFLAGS: -dv
146param=		twice
147VARNAME=	VAR.$${param}	# Indirect variable name because of the '$',
148				# to avoid difficult escaping rules.
149
150${VARNAME}=	initial-value	# Sets 'VAR.${param}' to 'expanded'.
151.if defined(VAR.twice)		# At this point, the '$$' is not expanded.
152.  error
153.endif
154.if ${${VARNAME}::=assigned-value} # Here the variable name gets expanded once
155.  error			# too often.
156.endif
157.if defined(VAR.twice)
158.  error The variable name in the '::=' modifier is expanded once too often.
159.endif
160.if ${${VARNAME}} != "assigned-value"
161.  error
162.endif
163.MAKEFLAGS: -d0
164
165
166# Conditional directives are evaluated in command line scope.  An assignment
167# modifier that creates a new variable creates it in the command line scope.
168# Existing variables are updated in their previous scope, and environment
169# variables are created in the global scope, as in other situations.
170.MAKEFLAGS: CMD_CMD_VAR=cmd-value
171CMD_GLOBAL_VAR=global-value
172export CMD_ENV_VAR=env-value
173.MAKEFLAGS: -dv
174# expect-reset
175# expect: Command: CMD_CMD_VAR = new-value
176# expect: Global: CMD_GLOBAL_VAR = new-value
177# expect: Global: CMD_ENV_VAR = new-value
178# expect: Global: ignoring delete 'CMD_NEW_VAR' as it is not found
179# expect: Command: CMD_NEW_VAR = new-value
180.if ${CMD_CMD_VAR::=new-value} \
181  || ${CMD_GLOBAL_VAR::=new-value} \
182  || ${CMD_ENV_VAR::=new-value} \
183  || "${CMD_NEW_VAR::=new-value}"
184.  error
185.endif
186.MAKEFLAGS: -d0
187
188# Run the 'target' test in a separate sub-make, with reduced debug logging.
189all: run-target
190run-target: .PHONY
191	@${MAKE} -r -f ${MAKEFILE} -dv target 2>&1 | grep ': TARGET_'
192
193.else # make(target)
194
195# The commands of a target are evaluated in target scope.  An assignment
196# modifier that creates a new variable creates it in the target scope.
197# Existing variables are updated in their previous scope, and environment
198# variables are created in the global scope, as in other situations.
199#
200# expect: target: TARGET_TARGET_VAR = new-value
201# expect: Global: TARGET_GLOBAL_VAR = new-value
202# expect: Global: TARGET_ENV_VAR = new-value
203# expect: target: TARGET_NEW_VAR = new-value
204.MAKEFLAGS: TARGET_CMD_VAR=cmd-value
205TARGET_GLOBAL_VAR=global-value
206export TARGET_ENV_VAR=env-value
207target: .PHONY TARGET_TARGET_VAR=target-value
208	: ${TARGET_TARGET_VAR::=new-value}
209	: ${TARGET_CMD_VAR::=new-value}
210	: ${TARGET_GLOBAL_VAR::=new-value}
211	: ${TARGET_ENV_VAR::=new-value}
212	: ${TARGET_NEW_VAR::=new-value}
213
214.endif
215