diff options
Diffstat (limited to 'unit-tests/var-op-expand.mk')
| -rw-r--r-- | unit-tests/var-op-expand.mk | 105 |
1 files changed, 104 insertions, 1 deletions
diff --git a/unit-tests/var-op-expand.mk b/unit-tests/var-op-expand.mk index ff62668a8ada..237f7baf1c62 100644 --- a/unit-tests/var-op-expand.mk +++ b/unit-tests/var-op-expand.mk @@ -1,8 +1,14 @@ -# $NetBSD: var-op-expand.mk,v 1.11 2021/01/01 23:07:48 sjg Exp $ +# $NetBSD: var-op-expand.mk,v 1.15 2021/11/30 23:52:19 rillig Exp $ # # Tests for the := variable assignment operator, which expands its # right-hand side. +# +# See also: +# varname-dot-make-save_dollars.mk +# Force the test results to be independent of the default value of this +# setting, which is 'yes' for NetBSD's usr.bin/make but 'no' for the bmake +# distribution and pkgsrc/devel/bmake. .MAKE.SAVE_DOLLARS:= yes # If the right-hand side does not contain a dollar sign, the ':=' assignment @@ -174,5 +180,102 @@ VAR_SUBST_${UNDEF}:= assigned by ':=' . error .endif + +# The following test case demonstrates that the variable 'LATER' is preserved +# in the ':=' assignment since the variable 'LATER' is not yet defined. +# After the assignment to 'LATER', evaluating the variable 'INDIRECT' +# evaluates 'LATER' as well. +# +.undef LATER +INDIRECT:= ${LATER:S,value,replaced,} +.if ${INDIRECT} != "" +. error +.endif +LATER= late-value +.if ${INDIRECT} != "late-replaced" +. error +.endif + + +# Same as the test case above, except for the additional modifier ':tl' when +# evaluating the variable 'INDIRECT'. Nothing surprising here. +.undef LATER +.undef later +INDIRECT:= ${LATER:S,value,replaced,} +.if ${INDIRECT:tl} != "" +. error +.endif +LATER= uppercase-value +later= lowercase-value +.if ${INDIRECT:tl} != "uppercase-replaced" +. error +.endif + + +# Similar to the two test cases above, the situation gets a bit more involved +# here, due to the double indirection. The variable 'indirect' is supposed to +# be the lowercase version of the variable 'INDIRECT'. +# +# The assignment operator ':=' for the variable 'INDIRECT' could be a '=' as +# well, it wouldn't make a difference in this case. The crucial detail is the +# assignment operator ':=' for the variable 'indirect'. During this +# assignment, the variable modifier ':S,value,replaced,' is converted to +# lowercase, which turns 'S' into 's', thus producing an unknown modifier. +# In this case, make issues a warning, but in cases where the modifier +# includes a '=', the modifier would be interpreted as a SysV-style +# substitution like '.c=.o', and make would not issue a warning, leading to +# silent unexpected behavior. +# +# As of 2021-11-20, the actual behavior is unexpected. Fixing it is not +# trivial. When the assignment to 'indirect' takes place, the expressions +# from the nested expression could be preserved, like this: +# +# Start with: +# +# indirect:= ${INDIRECT:tl} +# +# Since INDIRECT is defined, expand it, remembering that the modifier +# ':tl' must still be applied to the final result. +# +# indirect:= ${LATER:S,value,replaced,} \ +# OK \ +# ${LATER:value=sysv} +# +# The variable 'LATER' is not defined. An idea may be to append the +# remaining modifier ':tl' to each expression that is starting with an +# undefined variable, resulting in: +# +# indirect:= ${LATER:S,value,replaced,:tl} \ +# OK \ +# ${LATER:value=sysv:tl} +# +# This would work for the first expression. The second expression ends +# with the SysV modifier ':from=to', and when this modifier is parsed, +# it consumes all characters until the end of the expression, which in +# this case would replace the suffix 'value' with the literal 'sysv:tl', +# ignoring that the ':tl' was intended to be an additional modifier. +# +# Due to all of this, this surprising behavior is not easy to fix. +# +.undef LATER +.undef later +INDIRECT:= ${LATER:S,value,replaced,} OK ${LATER:value=sysv} +indirect:= ${INDIRECT:tl} +# expect+1: Unknown modifier "s,value,replaced," +.if ${indirect} != " ok " +. error +.else +. warning XXX Neither branch should be taken. +.endif +LATER= uppercase-value +later= lowercase-value +# expect+1: Unknown modifier "s,value,replaced," +.if ${indirect} != "uppercase-replaced ok uppercase-sysv" +. warning XXX Neither branch should be taken. +.else +. error +.endif + + all: @:; |