diff options
Diffstat (limited to 'unit-tests/var-scope-local.mk')
| -rw-r--r-- | unit-tests/var-scope-local.mk | 37 |
1 files changed, 22 insertions, 15 deletions
diff --git a/unit-tests/var-scope-local.mk b/unit-tests/var-scope-local.mk index 1ff025299bf7..ed1362444504 100644 --- a/unit-tests/var-scope-local.mk +++ b/unit-tests/var-scope-local.mk @@ -1,4 +1,4 @@ -# $NetBSD: var-scope-local.mk,v 1.4 2022/02/05 10:41:15 rillig Exp $ +# $NetBSD: var-scope-local.mk,v 1.5 2022/02/09 21:09:24 rillig Exp $ # # Tests for target-local variables, such as ${.TARGET} or $@. These variables # are relatively short-lived as they are created just before making the @@ -18,7 +18,7 @@ # these expressions to expand right in time when the target-local variables # are actually set. # -# Conditions like the ones below are evaluated in the scope of the command +# Conditions from .if directives are evaluated in the scope of the command # line, which means that variables from the command line, from the global # scope and from the environment are resolved, in this order (but see the # command line option '-e'). In that phase, expressions involving @@ -33,15 +33,16 @@ # expressions like ${@}, ${.TARGET} ${VAR:Mpattern} (see Var_Parse, # ParseVarname). # -# In the following condition, make does not expand '$@' but instead changes it -# to the long-format alias '$(.TARGET)'; note that the alias is not written -# with braces, as would be common in BSD makefiles, but with parentheses. -# This alternative form behaves equivalently though. +# In the following condition, make expands '$@' to the long-format alias +# '$(.TARGET)'; note that the alias is not written with braces, as would be +# common in BSD makefiles, but with parentheses. This alternative spelling +# behaves the same though. .if $@ != "\$\(.TARGET)" . error .endif -# In the long form of writing a target-local variable, the expression is -# preserved exactly as written, no matter whether with '{' or '('. +# In the long form of writing a target-local variable, the text of the +# expression is preserved exactly as written, no matter whether it is written +# with '{' or '('. .if ${@} != "\$\{@}" . error .endif @@ -60,7 +61,7 @@ # In the following examples, the expressions are based on target-local # variables but use the modifier ':L', which turns an undefined expression # into a defined one. At the end of evaluating the expression, the state of -# the expression is not 'undefined' anymore, and the value of the expression +# the expression is not 'undefined' anymore. The value of the expression # is the name of the variable, since that's what the modifier ':L' does. .if ${@:L} != "@" . error @@ -164,10 +165,11 @@ var-scope-local-append.o: VAR+= local var-scope-local-append.o: VAR += to ${.TARGET} # To access the value of a global variable, use a variable expression. This # expression is expanded before parsing the whole dependency line. Since the -# expansion happens to the right of both the dependency operator ':' and also -# to the right of the assignment operator '=', the expanded text does not -# affect the dependency or the variable assignment structurally. The -# effective variable assignment, after expanding the whole line first, is thus +# expansion happens to the right of the dependency operator ':', the expanded +# text does not influence parsing of the dependency line. Since the expansion +# happens to the right of the assignment operator '=', the expanded text does +# not influence the parsing of the variable assignment. The effective +# variable assignment, after expanding the whole line first, is thus # 'VAR= global+local'. # expect: : Making var-scope-local-append-global.o with VAR="global+local". var-scope-local-append-global.o: VAR= ${VAR}+local @@ -182,17 +184,22 @@ var-scope-local-default.o: VAR ?= second # Using the variable assignment operator ':=' provides another way of # accessing a global variable and extending it with local modifications. The # '$' has to be written as '$$' though to survive the expansion of the -# dependency line as a whole. +# dependency line as a whole. After that, the parser sees the variable +# assignment as 'VAR := ${VAR}+local' and searches for the variable 'VAR' in +# the usual scopes, picking up the variable from the global scope. +# expect: : Making var-scope-local-subst.o with VAR="global+local". var-scope-local-subst.o: VAR := $${VAR}+local # The variable assignment operator '!=' assigns the output of the shell -# command, as everywhere else. +# command, as everywhere else. The shell command is run when the dependency +# line is parsed. var-scope-local-shell.o: VAR != echo output # While VAR=use will be set for a .USE node, it will never be seen since only # the ultimate target's context is searched; the variable assignments from the # .USE target are not copied to the ultimate target's. +# expect: : var-scope-local-use.o uses .USE VAR="global" a_use: .USE VAR=use : ${.TARGET} uses .USE VAR="${VAR}" |