escape.mk revision 292068
1# $Id: escape.mk,v 1.1.1.2 2014/11/06 01:40:37 sjg Exp $ 2# 3# Test backslash escaping. 4 5# Extracts from the POSIX 2008 specification 6# <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/make.html>: 7# 8# Comments start with a <number-sign> ( '#' ) and continue until an 9# unescaped <newline> is reached. 10# 11# When an escaped <newline> (one preceded by a <backslash>) is found 12# anywhere in the makefile except in a command line, an include 13# line, or a line immediately preceding an include line, it shall 14# be replaced, along with any leading white space on the following 15# line, with a single <space>. 16# 17# When an escaped <newline> is found in a command line in a 18# makefile, the command line shall contain the <backslash>, the 19# <newline>, and the next line, except that the first character of 20# the next line shall not be included if it is a <tab>. 21# 22# When an escaped <newline> is found in an include line or in a 23# line immediately preceding an include line, the behavior is 24# unspecified. 25# 26# Notice that the behaviour of <backslash><backslash> or 27# <backslash><anything other than newline> is not mentioned. I think 28# this implies that <backslash> should be taken literally everywhere 29# except before <newline>. 30# 31# Our practice, despite what POSIX might say, is that "\#" 32# in a variable assignment stores "#" as part of the value. 33# The "\" is not taken literally, and the "#" does not begin a comment. 34# 35# Also, our practice is that an even number of backslashes before a 36# newline in a variable assignment simply stores the backslashes as part 37# of the value, and treats the newline as though it was not escaped. 38# Similarly, ann even number of backslashes before a newline in a 39# command simply uses the backslashes as part of the command test, but 40# does not escape the newline. This is compatible with GNU make. 41 42all: .PHONY 43# We will add dependencies like "all: yet-another-test" later. 44 45# Some variables to be expanded in tests 46# 47a = aaa 48A = ${a} 49 50# Backslash at end of line in a comment\ 51should continue the comment. \ 52# This is also tested in comment.mk. 53 54__printvars: .USE .MADE 55 @echo ${.TARGET} 56 ${.ALLSRC:@v@ printf "%s=:%s:\n" ${v:Q} ${${v}:Q}; @} 57 58# Embedded backslash in variable should be taken literally. 59# 60VAR1BS = 111\111 61VAR1BSa = 111\${a} 62VAR1BSA = 111\${A} 63VAR1BSda = 111\$${a} 64VAR1BSdA = 111\$${A} 65VAR1BSc = 111\# backslash escapes comment char, so this is part of the value 66VAR1BSsc = 111\ # This is a comment. Value ends with <backslash><space> 67 68all: var-1bs 69var-1bs: .PHONY __printvars VAR1BS VAR1BSa VAR1BSA VAR1BSda VAR1BSdA \ 70 VAR1BSc VAR1BSsc 71 72# Double backslash in variable should be taken as two literal backslashes. 73# 74VAR2BS = 222\\222 75VAR2BSa = 222\\${a} 76VAR2BSA = 222\\${A} 77VAR2BSda = 222\\$${a} 78VAR2BSdA = 222\\$${A} 79VAR2BSc = 222\\# backslash does not escape comment char, so this is a comment 80VAR2BSsc = 222\\ # This is a comment. Value ends with <backslash><backslash> 81 82all: var-2bs 83var-2bs: .PHONY __printvars VAR2BS VAR2BSa VAR2BSA VAR2BSda VAR2BSdA \ 84 VAR2BSc VAR2BSsc 85 86# Backslash-newline in a variable setting is replaced by a single space. 87# 88VAR1BSNL = 111\ 89111 90VAR1BSNLa = 111\ 91${a} 92VAR1BSNLA = 111\ 93${A} 94VAR1BSNLda = 111\ 95$${a} 96VAR1BSNLdA = 111\ 97$${A} 98VAR1BSNLc = 111\ 99# this should be processed as a comment 100VAR1BSNLsc = 111\ 101 # this should be processed as a comment 102 103all: var-1bsnl 104var-1bsnl: .PHONY 105var-1bsnl: .PHONY __printvars \ 106 VAR1BSNL VAR1BSNLa VAR1BSNLA VAR1BSNLda VAR1BSNLdA \ 107 VAR1BSNLc VAR1BSNLsc 108 109# Double-backslash-newline in a variable setting. 110# Both backslashes should be taken literally, and the newline is NOT escaped. 111# 112# The second lines below each end with '=' so that they will not 113# generate syntax errors regardless of whether or not they are 114# treated as part of the value. 115# 116VAR2BSNL = 222\\ 117222= 118VAR2BSNLa = 222\\ 119${a}= 120VAR2BSNLA = 222\\ 121${A}= 122VAR2BSNLda = 222\\ 123$${a}= 124VAR2BSNLdA = 222\\ 125$${A}= 126VAR2BSNLc = 222\\ 127# this should be processed as a comment 128VAR2BSNLsc = 222\\ 129 # this should be processed as a comment 130 131all: var-2bsnl 132var-2bsnl: .PHONY __printvars \ 133 VAR2BSNL VAR2BSNLa VAR2BSNLA VAR2BSNLda VAR2BSNLdA \ 134 VAR2BSNLc VAR2BSNLsc 135 136# Triple-backslash-newline in a variable setting. 137# First two should be taken literally, and last should escape the newline. 138# 139# The second lines below each end with '=' so that they will not 140# generate syntax errors regardless of whether or not they are 141# treated as part of the value. 142# 143VAR3BSNL = 333\\\ 144333= 145VAR3BSNLa = 333\\\ 146${a}= 147VAR3BSNLA = 333\\\ 148${A}= 149VAR3BSNLda = 333\\\ 150$${a}= 151VAR3BSNLdA = 333\\\ 152$${A}= 153VAR3BSNLc = 333\\\ 154# this should be processed as a comment 155VAR3BSNLsc = 333\\\ 156 # this should be processed as a comment 157 158all: var-3bsnl 159var-3bsnl: .PHONY __printvars \ 160 VAR3BSNL VAR3BSNLa VAR3BSNLA VAR3BSNLda VAR3BSNLdA \ 161 VAR3BSNLc VAR3BSNLsc 162 163# Backslash-newline in a variable setting, plus any amount of white space 164# on the next line, is replaced by a single space. 165# 166VAR1BSNL00= first line\ 167 168# above line is entirely empty, and this is a comment 169VAR1BSNL0= first line\ 170no space on second line 171VAR1BSNLs= first line\ 172 one space on second line 173VAR1BSNLss= first line\ 174 two spaces on second line 175VAR1BSNLt= first line\ 176 one tab on second line 177VAR1BSNLtt= first line\ 178 two tabs on second line 179VAR1BSNLxx= first line\ 180 many spaces and tabs [ ] on second line 181 182all: var-1bsnl-space 183var-1bsnl-space: .PHONY __printvars \ 184 VAR1BSNL00 VAR1BSNL0 VAR1BSNLs VAR1BSNLss VAR1BSNLt VAR1BSNLtt \ 185 VAR1BSNLxx 186 187# Backslash-newline in a command is retained. 188# 189# The "#" in "# second line without space" makes it a comment instead 190# of a syntax error if the preceding line is parsed incorretly. 191# The ":" in "third line':" makes it look like the start of a 192# target instead of a syntax error if the first line is parsed incorrectly. 193# 194all: cmd-1bsnl 195cmd-1bsnl: .PHONY 196 @echo ${.TARGET} 197 echo :'first line\ 198#second line without space\ 199third line': 200 echo :'first line\ 201 second line spaces should be retained': 202 echo :'first line\ 203 second line tab should be elided': 204 echo :'first line\ 205 only one tab should be elided, second tab remains' 206 207# When backslash-newline appears at the end of a command script, 208# both the backslash and the newline should be passed to the shell. 209# The shell should elide the backslash-newline. 210# 211all: cmd-1bsnl-eof 212cmd-1bsnl-eof: 213 @echo ${.TARGET} 214 echo :'command ending with backslash-newline'; \ 215 216# above line must be blank 217 218# Double-backslash-newline in a command. 219# Both backslashes are retained, but the newline is not escaped. 220# XXX: This may differ from POSIX, but matches gmake. 221# 222# When make passes two backslashes to the shell, the shell will pass one 223# backslash to the echo commant. 224# 225all: cmd-2bsnl 226cmd-2bsnl: .PHONY 227 @echo ${.TARGET} 228 echo take one\\ 229# this should be a comment 230 echo take two\\ 231 echo take three\\ 232 233# Triple-backslash-newline in a command is retained. 234# 235all: cmd-3bsnl 236cmd-3bsnl: .PHONY 237 @echo ${.TARGET} 238 echo :'first line\\\ 239#second line without space\\\ 240third line': 241 echo :'first line\\\ 242 second line spaces should be retained': 243 echo :'first line\\\ 244 second line tab should be elided': 245 echo :'first line\\\ 246 only one tab should be elided, second tab remains' 247