diff options
Diffstat (limited to 'unit-tests/varmod-match-escape.mk')
| -rwxr-xr-x | unit-tests/varmod-match-escape.mk | 60 |
1 files changed, 56 insertions, 4 deletions
diff --git a/unit-tests/varmod-match-escape.mk b/unit-tests/varmod-match-escape.mk index 7913bb476ae7..5115d1b565df 100755 --- a/unit-tests/varmod-match-escape.mk +++ b/unit-tests/varmod-match-escape.mk @@ -1,4 +1,4 @@ -# $NetBSD: varmod-match-escape.mk,v 1.1 2020/08/16 20:03:53 rillig Exp $ +# $NetBSD: varmod-match-escape.mk,v 1.5 2020/11/01 19:49:28 rillig Exp $ # # As of 2020-08-01, the :M and :N modifiers interpret backslashes differently, # depending on whether there was a variable expression somewhere before the @@ -9,12 +9,64 @@ # are unescaped, and in the pattern matching these have the same meaning as # their plain variants '{', '}' and ':'. In the pattern matching from # Str_Match, only \*, \? or \[ would make a noticeable difference. + +.MAKEFLAGS: -dcv + SPECIALS= \: : \\ * \* -RELEVANT= yes .if ${SPECIALS:M${:U}\:} != ${SPECIALS:M\:${:U}} -.warning unexpected +. warning unexpected +.endif + +# And now both cases combined: A single modifier with both an escaped ':' +# as well as a variable expression that expands to a ':'. +# +# XXX: As of 2020-11-01, when an escaped ':' occurs before the variable +# expression, the whole modifier text is subject to unescaping '\:' to ':', +# before the variable expression is expanded. This means that the '\:' in +# the variable expression is expanded as well, turning ${:U\:} into a simple +# ${:U:}, which silently expands to an empty string, instead of generating +# an error message. +# +# XXX: As of 2020-11-01, the modifier on the right-hand side of the +# comparison is parsed differently though. First, the variable expression +# is parsed, resulting in ':' and needSubst=TRUE. After that, the escaped +# ':' is seen, and this time, copy=TRUE is not executed but stays copy=FALSE. +# Therefore the escaped ':' is kept as-is, and the final pattern becomes +# ':\:'. +# +# If ApplyModifier_Match had used the same parsing algorithm as Var_Subst, +# both patterns would end up as '::'. +# +VALUES= : :: :\: +.if ${VALUES:M\:${:U\:}} != ${VALUES:M${:U\:}\:} +. warning XXX: Oops +.endif + +.MAKEFLAGS: -d0 + +# XXX: As of 2020-11-01, unlike all other variable modifiers, a '$' in the +# :M and :N modifiers is written as '$$', not as '\$'. This is confusing, +# undocumented and hopefully not used in practice. +.if ${:U\$:M$$} != "\$" +. error +.endif + +# XXX: As of 2020-11-01, unlike all other variable modifiers, '\$' is not +# parsed as an escaped '$'. Instead, ApplyModifier_Match first scans for +# the ':' at the end of the modifier, which results in the pattern '\$'. +# No unescaping takes place since the pattern neither contained '\:' nor +# '\{' nor '\}'. But the text is expanded, and a lonely '$' at the end +# is silently discarded. The resulting expanded pattern is thus '\', that +# is a single backslash. +.if ${:U\$:M\$} != "" +. error +.endif + +# In lint mode, the case of a lonely '$' is covered with an error message. +.MAKEFLAGS: -dL +.if ${:U\$:M\$} != "" +. error .endif -RELEVANT= no all: @:; |