321 lines
10 KiB
Makefile
321 lines
10 KiB
Makefile
# $NetBSD: directive-for.mk,v 1.25 2024/04/20 10:18:55 rillig Exp $
|
|
#
|
|
# Tests for the .for directive.
|
|
#
|
|
# TODO: Describe naming conventions for the loop variables.
|
|
# .for f in values
|
|
# .for file in values
|
|
# .for _FILE_ in values
|
|
# .for .FILE. in values
|
|
# .for _f_ in values
|
|
#
|
|
# See also:
|
|
# varmod-loop.mk The ':@var@...@' modifier
|
|
|
|
# A typical use case for a .for loop is to populate a variable with a list of
|
|
# values depending on other variables. In simple cases, the same effect can
|
|
# be achieved using the ':@var@${var}@' modifier.
|
|
.undef NUMBERS
|
|
.for num in 1 2 3
|
|
NUMBERS+= ${num}
|
|
.endfor
|
|
.if ${NUMBERS} != "1 2 3"
|
|
. error
|
|
.endif
|
|
|
|
|
|
# The .for loop also works for multiple iteration variables.
|
|
# This is something that the modifier :@ cannot do as easily.
|
|
.for name value in VARNAME value NAME2 value2
|
|
${name}= ${value}
|
|
.endfor
|
|
.if ${VARNAME} != "value" || ${NAME2} != "value2"
|
|
. error
|
|
.endif
|
|
|
|
|
|
# The .for loop splits the items at whitespace, taking quotes into account,
|
|
# just like the :M or :S modifiers.
|
|
#
|
|
# Until 2012-06-03, the .for loop had split the items exactly at whitespace,
|
|
# without taking the quotes into account. This had resulted in 10 words.
|
|
.undef WORDS
|
|
.for var in one t\ w\ o "three three" 'four four' `five six`
|
|
WORDS+= counted
|
|
.endfor
|
|
.if ${WORDS:[#]} != 6
|
|
. error
|
|
.endif
|
|
|
|
|
|
# In the body of the .for loop, the iteration variables can be accessed
|
|
# like normal variables, even though they are not really variables.
|
|
#
|
|
# Instead, before interpreting the body of the .for loop, the body is
|
|
# generated by replacing each expression ${var} with ${:U1}, ${:U2} and so
|
|
# on.
|
|
#
|
|
# A noticeable effect of this implementation technique is that the .for
|
|
# iteration variables and the normal global variables live in separate
|
|
# namespaces and do not influence each other. The "scope" of the .for loop
|
|
# variables is restricted to the current makefile, it does not reach over to
|
|
# any included makefiles.
|
|
var= value before
|
|
var2= value before
|
|
.for var var2 in 1 2 3 4
|
|
.endfor
|
|
.if ${var} != "value before"
|
|
. warning After the .for loop, var must still have its original value.
|
|
.endif
|
|
.if ${var2} != "value before"
|
|
. warning After the .for loop, var2 must still have its original value.
|
|
.endif
|
|
|
|
# Everything from the paragraph above also applies if the loop body is
|
|
# empty. In this particular example, the items to be iterated are empty as
|
|
# well.
|
|
var= value before
|
|
var2= value before
|
|
.for var var2 in ${:U}
|
|
.endfor
|
|
.if ${var} != "value before"
|
|
. warning After the .for loop, var must still have its original value.
|
|
.endif
|
|
.if ${var2} != "value before"
|
|
. warning After the .for loop, var2 must still have its original value.
|
|
.endif
|
|
|
|
# Before for.c 1.39 from 2008-12-21, the values of the iteration variables
|
|
# were simply inserted as plain text and then parsed as usual, which made it
|
|
# possible to achieve all kinds of strange effects, such as generating '.if'
|
|
# directives or inserting '$' characters in random places, thereby changing
|
|
# how following '$' are interpreted.
|
|
#
|
|
# Before that date, the .for loop below expanded to:
|
|
# EXPANSION+= value
|
|
# Since that date, the .for loop below expands to:
|
|
# EXPANSION${:U+}= value
|
|
#
|
|
EXPANSION= before
|
|
EXPANSION+ = before
|
|
.for plus in +
|
|
EXPANSION${plus}= value
|
|
.endfor
|
|
.if ${EXPANSION} != "before"
|
|
. error This must be a make from before 2009.
|
|
.endif
|
|
.if ${EXPANSION+} != "value"
|
|
. error This must be a make from before 2009.
|
|
.endif
|
|
|
|
# When the outer .for loop is expanded, it sees the expression ${i} and
|
|
# expands it. The inner loop then only sees the expression ${:Uouter} and
|
|
# has nothing more to expand.
|
|
.for i in outer
|
|
. for i in inner
|
|
# expect+1: outer
|
|
. info ${i}
|
|
. endfor
|
|
.endfor
|
|
|
|
|
|
# From https://gnats.netbsd.org/29985.
|
|
#
|
|
# Until 2008-12-21, the .for loop was expanded by replacing the variable
|
|
# value literally in the body. This could lead to situations where the
|
|
# characters from the variable value were interpreted as markup rather than
|
|
# plain text.
|
|
#
|
|
# Until 2012-06-03, the .for loop had split the words at whitespace, without
|
|
# taking quotes into account. This made it possible to have variable values
|
|
# like "a:\ a:\file.txt" that ended in a single backslash. Since then, the
|
|
# variable values have been replaced with expressions of the form ${:U...},
|
|
# which are not interpreted as code anymore.
|
|
.for path in a:\ a:\file.txt d:\\ d:\\file.txt
|
|
. info ${path}
|
|
.endfor
|
|
# expect-2: a:\ a:\file.txt
|
|
# expect-3: d:\\
|
|
# expect-4: d:\\file.txt
|
|
|
|
|
|
# Ensure that braces and parentheses are properly escaped by the .for loop.
|
|
# Each line must print the same word 3 times.
|
|
# See ForLoop_SubstBody.
|
|
.for v in ( [ { ) ] } (()) [[]] {{}} )( ][ }{
|
|
. info $v ${v} $(v)
|
|
.endfor
|
|
# expect-02: ( ( (
|
|
# expect-03: [ [ [
|
|
# expect-04: { { {
|
|
# expect-05: ) ) )
|
|
# expect-06: ] ] ]
|
|
# expect-07: } } }
|
|
# expect-08: (()) (()) (())
|
|
# expect-09: [[]] [[]] [[]]
|
|
# expect-10: {{}} {{}} {{}}
|
|
# expect-11: )( )( )(
|
|
# expect-12: ][ ][ ][
|
|
# expect-13: }{ }{ }{
|
|
|
|
# Before 2023-05-09, the variable names could contain arbitrary characters,
|
|
# except for whitespace, allowing for creative side effects, as usual for
|
|
# arbitrary code injection.
|
|
var= outer
|
|
# expect+1: invalid character ':' in .for loop variable name
|
|
.for var:Q in value "quoted"
|
|
. info <${var}> <${var:Q}> <${var:Q:Q}>
|
|
.endfor
|
|
|
|
# Before 2023-05-09, when variable names could contain '$', the short
|
|
# expression '$$' was preserved, the long expressions were substituted.
|
|
# expect+1: invalid character '$' in .for loop variable name
|
|
.for $ in value
|
|
. info <$$> <${$}> <$($)>
|
|
.endfor
|
|
|
|
|
|
# https://gnats.netbsd.org/53146 mentions the idea of using a dynamic
|
|
# variable name in .for loops, based on some other variable. The .for loops
|
|
# are already tricky enough to understand in detail, even without this
|
|
# possibility, therefore the variable names are restricted to using harmless
|
|
# characters only.
|
|
INDIRECT= direct
|
|
# expect+1: invalid character '$' in .for loop variable name
|
|
.for $(INDIRECT) in value
|
|
# If the variable name could be chosen dynamically, the iteration variable
|
|
# might have been 'direct', thereby expanding the expression '${direct}'.
|
|
. info <$(INDIRECT)> <$(direct)> <$($(INDIRECT))>
|
|
.endfor
|
|
|
|
|
|
# Regular global variables and the "variables" from the .for loop don't
|
|
# interfere with each other. In the following snippet, the variable 'DIRECT'
|
|
# is used both as a global variable, as well as an iteration variable in the
|
|
# .for loop. The expression '${INDIRECT}' refers to the global variable, not
|
|
# to the one from the .for loop.
|
|
DIRECT= global
|
|
INDIRECT= ${DIRECT}
|
|
.for DIRECT in iteration
|
|
. if "${DIRECT} ${INDIRECT}" != "iteration global"
|
|
. error
|
|
. endif
|
|
.endfor
|
|
|
|
|
|
# XXX: A parse error or evaluation error in the items of the .for loop
|
|
# should skip the whole loop. As of 2023-05-09, the loop is expanded as
|
|
# usual.
|
|
# expect+1: while evaluating "${:Uword2:Z}-after word3": Unknown modifier "Z"
|
|
.for var in word1 before-${:Uword2:Z}-after word3
|
|
. info XXX: Should not reach ${var}
|
|
.endfor
|
|
# expect-2: XXX: Should not reach word1
|
|
# expect-3: XXX: Should not reach before--after
|
|
# expect-4: XXX: Should not reach word3
|
|
|
|
|
|
# An empty list of variables to the left of the 'in' is a parse error.
|
|
.for in value # expect+0: no iteration variables in for
|
|
. error
|
|
.endfor
|
|
|
|
# An empty list of iteration values to the right of the 'in' is accepted.
|
|
# Unlike in the shell, it is not a parse error.
|
|
.for var in
|
|
. error
|
|
.endfor
|
|
|
|
# If the iteration values become empty after expanding the expressions, the
|
|
# body of the loop is not evaluated. It is not a parse error.
|
|
.for var in ${:U}
|
|
. error
|
|
.endfor
|
|
|
|
|
|
# The loop body can be empty.
|
|
.for var in 1 2 3
|
|
.endfor
|
|
|
|
|
|
# A mismatched .if inside a .for loop is detected each time when the loop body
|
|
# is processed.
|
|
.for var in value
|
|
. if 0
|
|
.endfor # expect+0: 1 open conditional
|
|
|
|
# If there are no iteration values, the loop body is not processed, and the
|
|
# check for mismatched conditionals is not performed.
|
|
.for var in ${:U}
|
|
. if 0
|
|
.endfor
|
|
|
|
|
|
# When a .for without the corresponding .endfor occurs in an inactive branch
|
|
# of an .if, the .for directive is just skipped, it does not even need a
|
|
# corresponding .endfor. In other words, the behavior of the parser depends
|
|
# on the actual values of the conditions in the .if clauses.
|
|
.if 0
|
|
. for var in value # does not need a corresponding .endfor
|
|
.endif
|
|
.endfor # expect+0: for-less endfor
|
|
.endif # expect+0: if-less endif
|
|
|
|
|
|
# When a .for without the corresponding .endfor occurs in an active branch of
|
|
# an .if, the parser just counts the number of .for and .endfor directives,
|
|
# without looking at any other directives.
|
|
.if 1
|
|
. for var in value
|
|
. endif # expect+0: if-less endif
|
|
. endfor # no 'for-less endfor'
|
|
.endif # no 'if-less endif'
|
|
|
|
|
|
# Before for.c 1.172 from 2023-05-08, when make parsed a .for loop, it
|
|
# assumed that there was no line continuation between the '.' and the 'for'
|
|
# or 'endfor', as there is no practical reason to break the line at this
|
|
# point.
|
|
#
|
|
# When make scanned the outer .for loop, it did not recognize the inner .for
|
|
# loop as such and instead treated it as an unknown directive. The body of
|
|
# the outer .for loop thus ended above the '.endfor'.
|
|
#
|
|
# When make scanned the inner .for loop, it did not recognize the inner
|
|
# .endfor as such, which led to a parse error 'Unexpected end of file in .for
|
|
# loop' from the '.endfor' line, followed by a second parse error 'for-less
|
|
# .endfor' from the '.\\n endfor' line.
|
|
.MAKEFLAGS: -df
|
|
.for outer in o
|
|
.\
|
|
for inner in i
|
|
.\
|
|
endfor
|
|
.endfor
|
|
.MAKEFLAGS: -d0
|
|
|
|
|
|
# When there is a variable definition 'scope=cmdline' from the command line
|
|
# (which has higher precedence than global variables) and a .for loop iterates
|
|
# over a variable of the same name, the expression '${scope}' expands to the
|
|
# value from the .for loop. This is because when the body of the .for loop is
|
|
# expanded, the expression '${scope}' is textually replaced with ${:Uloop}',
|
|
# without resolving any other variable names (ForLoop_SubstBody). Later, when
|
|
# the body of the .for loop is actually interpreted, the body text doesn't
|
|
# contain the word 'scope' anymore.
|
|
.MAKEFLAGS: scope=cmdline
|
|
.for scope in loop
|
|
. if ${scope} != "loop"
|
|
. error
|
|
. endif
|
|
.endfor
|
|
|
|
|
|
# Since at least 1993, iteration stops at the first newline.
|
|
# Back then, the .newline variable didn't exist, therefore it was unlikely
|
|
# that a newline ever occurred.
|
|
.for var in a${.newline}b${.newline}c
|
|
. info newline-item=(${var})
|
|
.endfor
|
|
# expect-2: newline-item=(a)
|