1# $NetBSD: deptgt-makeflags.mk,v 1.6 2020/11/15 20:20:58 rillig Exp $ 2# 3# Tests for the special target .MAKEFLAGS in dependency declarations, 4# which adds command line options later, at parse time. 5# 6# In these unit tests, it is often used to temporarily toggle the debug log 7# during parsing. 8 9# The -D option sets a variable in the "Global" scope and thus can be 10# undefined later. 11.MAKEFLAGS: -D VAR 12.if ${VAR} != 1 13. error 14.endif 15 16# Variables that are set via the -D command line option are normal global 17# variables and can thus be undefined later. 18.undef VAR 19.if defined(VAR) 20. error 21.endif 22 23# The -D command line option can define a variable again, after it has been 24# undefined. 25.MAKEFLAGS: -D VAR 26.if ${VAR} != 1 27. error 28.endif 29 30# The "dependency" for .MAKEFLAGS is split into words, interpreting the usual 31# quotes and escape sequences from the backslash. 32.MAKEFLAGS: VAR="value"' with'\ spaces 33.if ${VAR} != "value with spaces" 34. error 35.endif 36 37# Variables set on the command line as VAR=value are placed in the 38# "Command" scope and thus cannot be undefined. 39.undef VAR 40.if ${VAR} != "value with spaces" 41. error 42.endif 43 44# When parsing this line, each '$$' becomes '$', resulting in '$$$$'. 45# This is assigned to the variable DOLLAR. 46# In the condition, that variable is expanded, and at that point, each '$$' 47# becomes '$' again, the final expression is thus '$$'. 48.MAKEFLAGS: -dcv 49.MAKEFLAGS: DOLLAR=$$$$$$$$ 50.if ${DOLLAR} != "\$\$" 51.endif 52.MAKEFLAGS: -d0 53 54# An empty command line is skipped. 55.MAKEFLAGS: # none 56 57# Escape sequences like \n are interpreted. 58# The following line looks as if it assigned a newline to nl, but it doesn't. 59# Instead, the \n ends up as a line that is then interpreted as a variable 60# assignment. At that point, the line is simply "nl=\n", and the \n is 61# skipped since it is whitespace (see Parse_IsVar). 62.MAKEFLAGS: nl="\n" 63.if ${nl} != "" 64. error 65.endif 66 67# Next try at defining another newline variable. Since whitespace around the 68# variable value is trimmed, two empty variable expressions surround the 69# literal newline now. This prevents the newline from being skipped during 70# parsing. The ':=' assignment operator expands the empty variable 71# expressions, leaving only the newline as the variable value. 72# 73# This is one of the very few ways (maybe even the only one) to inject literal 74# newlines into a line that is being parsed. This may confuse the parser. 75# For example, in cond.c the parser only expects horizontal whitespace (' ' 76# and '\t'), but no newlines. 77#.MAKEFLAGS: -dcpv 78.MAKEFLAGS: nl:="$${:U}\n$${:U}" 79.if ${nl} != ${.newline} 80. error 81.endif 82#.MAKEFLAGS: -d0 83 84# Unbalanced quotes produce an error message. If they occur anywhere in the 85# command line, the whole command line is skipped. 86.MAKEFLAGS: VAR=previous 87.MAKEFLAGS: VAR=initial UNBALANCED=' 88.if ${VAR} != "previous" 89. error 90.endif 91 92all: 93 @:; 94