escape.mk revision 1.7
1 # $Id: escape.mk,v 1.7 2014/08/24 16:08:14 apb 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 newline 36 # in a variable assignment simply stores the backslashes as part of the 37 # value, and treats the newline as though it was not escaped. This 38 # is compatible with GNU make. 39 40 all: .PHONY 41 # We will add dependencies like "all: yet-another-test" later. 42 43 # Some variables to be expanded in tests 44 # 45 a = aaa 46 A = ${a} 47 48 # Backslash at end of line in a comment\ 49 should continue the comment. \ 50 # This is also tested in comment.mk. 51 52 __printvars: .USE .MADE 53 @echo ${.TARGET} 54 @${.ALLSRC:@v@ printf "%s=:%s:\n" ${v:Q} ${${v}:Q}; @} 55 56 # Embedded backslash in variable should be taken literally. 57 # 58 VAR1BS = 111\111 59 VAR1BSa = 111\${a} 60 VAR1BSA = 111\${A} 61 VAR1BSda = 111\$${a} 62 VAR1BSdA = 111\$${A} 63 VAR1BSc = 111\# backslash escapes comment char, so this is part of the value 64 VAR1BSsc = 111\ # This is a comment. Value ends with <backslash><space> 65 66 all: var-1bs 67 var-1bs: .PHONY __printvars VAR1BS VAR1BSa VAR1BSA VAR1BSda VAR1BSdA \ 68 VAR1BSc VAR1BSsc 69 70 # Double backslash in variable should be taken as two literal backslashes. 71 # 72 VAR2BS = 222\\222 73 VAR2BSa = 222\\${a} 74 VAR2BSA = 222\\${A} 75 VAR2BSda = 222\\$${a} 76 VAR2BSdA = 222\\$${A} 77 VAR2BSc = 222\\# backslash does not escape comment char, so this is a comment 78 VAR2BSsc = 222\\ # This is a comment. Value ends with <backslash><backslash> 79 80 all: var-2bs 81 var-2bs: .PHONY __printvars VAR2BS VAR2BSa VAR2BSA VAR2BSda VAR2BSdA \ 82 VAR2BSc VAR2BSsc 83 84 # Backslash-newline in a variable setting is replaced by a single space. 85 # 86 VAR1BSNL = 111\ 87 111 88 VAR1BSNLa = 111\ 89 ${a} 90 VAR1BSNLA = 111\ 91 ${A} 92 VAR1BSNLda = 111\ 93 $${a} 94 VAR1BSNLdA = 111\ 95 $${A} 96 VAR1BSNLc = 111\ 97 # this should be processed as a comment 98 VAR1BSNLsc = 111\ 99 # this should be processed as a comment 100 101 all: var-1bsnl 102 var-1bsnl: .PHONY 103 var-1bsnl: .PHONY __printvars \ 104 VAR1BSNL VAR1BSNLa VAR1BSNLA VAR1BSNLda VAR1BSNLdA \ 105 VAR1BSNLc VAR1BSNLsc 106 107 # Double-backslash-newline in a variable setting. 108 # Both backslashes should be taken literally, and the newline is NOT escaped. 109 # 110 # The second lines below each end with '=' so that they will not 111 # generate syntax errors regardless of whether or not they are 112 # treated as part of the value. 113 # 114 VAR2BSNL = 222\\ 115 222= 116 VAR2BSNLa = 222\\ 117 ${a}= 118 VAR2BSNLA = 222\\ 119 ${A}= 120 VAR2BSNLda = 222\\ 121 $${a}= 122 VAR2BSNLdA = 222\\ 123 $${A}= 124 VAR2BSNLc = 222\\ 125 # this should be processed as a comment 126 VAR2BSNLsc = 222\\ 127 # this should be processed as a comment 128 129 all: var-2bsnl 130 var-2bsnl: .PHONY __printvars \ 131 VAR2BSNL VAR2BSNLa VAR2BSNLA VAR2BSNLda VAR2BSNLdA \ 132 VAR2BSNLc VAR2BSNLsc 133 134 # Triple-backslash-newline in a variable setting. 135 # First two should be taken literally, and last should escape the newline. 136 # 137 # The second lines below each end with '=' so that they will not 138 # generate syntax errors regardless of whether or not they are 139 # treated as part of the value. 140 # 141 VAR3BSNL = 333\\\ 142 333= 143 VAR3BSNLa = 333\\\ 144 ${a}= 145 VAR3BSNLA = 333\\\ 146 ${A}= 147 VAR3BSNLda = 333\\\ 148 $${a}= 149 VAR3BSNLdA = 333\\\ 150 $${A}= 151 VAR3BSNLc = 333\\\ 152 # this should be processed as a comment 153 VAR3BSNLsc = 333\\\ 154 # this should be processed as a comment 155 156 all: var-3bsnl 157 var-3bsnl: .PHONY __printvars \ 158 VAR3BSNL VAR3BSNLa VAR3BSNLA VAR3BSNLda VAR3BSNLdA \ 159 VAR3BSNLc VAR3BSNLsc 160 161 # Backslash-newline in a variable setting, plus any amount of white space 162 # on the next line, is replaced by a single space. 163 # 164 VAR1BSNL00= first line\ 165 166 # above line is entirely empty, and this is a comment 167 VAR1BSNL0= first line\ 168 no space on second line 169 VAR1BSNLs= first line\ 170 one space on second line 171 VAR1BSNLss= first line\ 172 two spaces on second line 173 VAR1BSNLt= first line\ 174 one tab on second line 175 VAR1BSNLtt= first line\ 176 two tabs on second line 177 VAR1BSNLxx= first line\ 178 many spaces and tabs [ ] on second line 179 180 all: var-1bsnl-space 181 var-1bsnl-space: .PHONY __printvars \ 182 VAR1BSNL00 VAR1BSNL0 VAR1BSNLs VAR1BSNLss VAR1BSNLt VAR1BSNLtt \ 183 VAR1BSNLxx 184 185 # Backslash-newline in a command is retained. 186 # 187 # The "#" in "# second line without space" makes it a comment instead 188 # of a syntax error if the preceding line is parsed incorretly. 189 # The ":" in "third line':" makes it look like the start of a 190 # target instead of a syntax error if the first line is parsed incorrectly. 191 # 192 all: cmd-1bsnl 193 cmd-1bsnl: .PHONY 194 @echo ${.TARGET} 195 @echo :'first line\ 196 #second line without space\ 197 third line': 198 @echo :'first line\ 199 second line spaces should be retained': 200 @echo :'first line\ 201 second line tab should be elided': 202 @echo :'first line\ 203 only one tab should be elided, second tab remains' 204 205 # Double-backslash-newline in a command is retained. 206 # 207 all: cmd-2bsnl 208 cmd-2bsnl: .PHONY 209 @echo ${.TARGET} 210 @echo :'first line\\ 211 #second line without space\\ 212 third line': 213 @echo :'first line\\ 214 second line spaces should be retained': 215 @echo :'first line\\ 216 second line tab should be elided': 217 @echo :'first line\\ 218 only one tab should be elided, second tab remains' 219 220 # Triple-backslash-newline in a command is retained. 221 # 222 all: cmd-3bsnl 223 cmd-3bsnl: .PHONY 224 @echo ${.TARGET} 225 @echo :'first line\\\ 226 #second line without space\\\ 227 third line': 228 @echo :'first line\\\ 229 second line spaces should be retained': 230 @echo :'first line\\\ 231 second line tab should be elided': 232 @echo :'first line\\\ 233 only one tab should be elided, second tab remains' 234
Indexes created Wed Oct 01 07:09:59 GMT 2025