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|
# $NetBSD: directive-undef.mk,v 1.14 2024/04/20 10:18:55 rillig Exp $
#
# Tests for the .undef directive.
#
# See also:
# directive-misspellings.mk
# Before var.c 1.737 from 2020-12-19, .undef only undefined the first
# variable, silently skipping all further variable names.
#
# Before var.c 1.761 from 2020-12-22, .undef complained about too many
# arguments.
#
# Since var.c 1.761 from 2020-12-22, .undef handles multiple variable names
# just like the .export directive.
1= 1
2= 2
3= 3
.undef 1 2 3
.if ${1:U_}${2:U_}${3:U_} != ___
. warning $1$2$3
.endif
# Without any arguments, until var.c 1.736 from 2020-12-19, .undef tried
# to delete the variable with the empty name, which never exists; see
# varname-empty.mk. Since var.c 1.737 from 2020-12-19, .undef complains
# about a missing argument.
# expect+1: The .undef directive requires an argument
.undef
# Trying to delete the variable with the empty name is ok, it just won't
# ever do anything since that variable is never defined.
.undef ${:U}
# The argument of .undef is first expanded exactly once and then split into
# words, just like everywhere else. This prevents variables whose names
# contain spaces or unbalanced 'single' or "double" quotes from being
# undefined, but these characters do not appear in variables names anyway.
1= 1
2= 2
3= 3
${:U1 2 3}= one two three
VARNAMES= 1 2 3
.undef ${VARNAMES} # undefines the variables "1", "2" and "3"
.if ${${:U1 2 3}} != "one two three" # still there
. error
.endif
.if ${1:U_}${2:U_}${3:U_} != "___" # these have been undefined
. error
.endif
# A variable named " " cannot be undefined. There's no practical use case
# for such variables anyway.
SPACE= ${:U }
${SPACE}= space
.if !defined(${SPACE})
. error
.endif
.undef ${SPACE}
.if !defined(${SPACE})
. error
.endif
# A variable named "$" can be undefined since the argument to .undef is
# expanded exactly once, before being split into words.
DOLLAR= $$
${DOLLAR}= dollar
.if !defined(${DOLLAR})
. error
.endif
.undef ${DOLLAR}
.if defined(${DOLLAR})
. error
.endif
# Since var.c 1.762 from 2020-12-22, parse errors in the argument should be
# properly detected and should stop the .undef directive from doing any work.
#
# As of var.c 1.762, this doesn't happen though because the error handling
# in Var_Parse and Var_Subst is not done properly.
# expect+1: while evaluating variable "VARNAMES": Unknown modifier "Z"
.undef ${VARNAMES:L:Z}
UT_EXPORTED= exported-value
.export UT_EXPORTED
.if ${:!echo "\${UT_EXPORTED:-not-exported}"!} != "exported-value"
. error
.endif
.if !${.MAKE.EXPORTED:MUT_EXPORTED}
. error
.endif
.undef UT_EXPORTED # XXX: does not update .MAKE.EXPORTED
.if ${:!echo "\${UT_EXPORTED:-not-exported}"!} != "not-exported"
. error
.endif
.if ${.MAKE.EXPORTED:MUT_EXPORTED}
# expect+1: warning: UT_EXPORTED is still listed in .MAKE.EXPORTED even though spaceit is not exported anymore.
. warning UT_EXPORTED is still listed in .MAKE.EXPORTED even though $\
it is not exported anymore.
.endif
# When an exported variable is undefined, the variable is removed both from
# the global scope as well as from the environment.
DIRECT= direct
INDIRECT= in-${DIRECT}
.export DIRECT INDIRECT
.if ${DIRECT} != "direct"
. error
.endif
.if ${INDIRECT} != "in-direct"
. error
.endif
# Deletes the variables from the global scope and also from the environment.
# This applies to both variables, even though 'INDIRECT' is not actually
# exported yet since it refers to another variable.
.undef DIRECT # Separate '.undef' directives,
.undef INDIRECT # for backwards compatibility.
.if ${DIRECT:Uundefined} != "undefined"
. error
.endif
.if ${INDIRECT:Uundefined} != "undefined"
. error
.endif
# Since var.c 1.570 from 2020-10-06 and before var.c 1.1014 from 2022-03-26,
# make ran into an assertion failure when trying to undefine a variable that
# was based on an environment variable.
.if ${ENV_VAR} != "env-value" # see ./Makefile, ENV.directive-undef
. error
.endif
ENV_VAR+= appended # moves the short-lived variable to the
# global scope
.undef ENV_VAR # removes the variable from both the global
# scope and from the environment
all:
|
