[src/trunk]: src/usr.bin/make/unit-tests make(1): demonstrate obscure edge ca...

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/18b77f6948c2
branches:  trunk
changeset: 1012059:18b77f6948c2
user:      rillig <rillig%NetBSD.org@localhost>
date:      Mon Jul 20 16:27:55 2020 +0000

description:
make(1): demonstrate obscure edge case in SysV modifier

diffstat:

 usr.bin/make/unit-tests/sysv.exp |   2 ++
 usr.bin/make/unit-tests/sysv.mk  |  11 +++++++++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diffs (33 lines):

diff -r 6b4237f4306b -r 18b77f6948c2 usr.bin/make/unit-tests/sysv.exp
--- a/usr.bin/make/unit-tests/sysv.exp  Mon Jul 20 16:12:52 2020 +0000
+++ b/usr.bin/make/unit-tests/sysv.exp  Mon Jul 20 16:27:55 2020 +0000
@@ -15,4 +15,6 @@
 ax:Q b c d eb
 bcd.e
 &
+anchor-dollar: valux
+anchor-dollar: valux
 exit status 0
diff -r 6b4237f4306b -r 18b77f6948c2 usr.bin/make/unit-tests/sysv.mk
--- a/usr.bin/make/unit-tests/sysv.mk   Mon Jul 20 16:12:52 2020 +0000
+++ b/usr.bin/make/unit-tests/sysv.mk   Mon Jul 20 16:27:55 2020 +0000
@@ -1,6 +1,6 @@
-# $Id: sysv.mk,v 1.7 2020/07/19 22:04:27 rillig Exp $
+# $Id: sysv.mk,v 1.8 2020/07/20 16:27:55 rillig Exp $
 
-all: foo fun sam bla words ampersand
+all: foo fun sam bla words ampersand anchor-dollar
 
 FOO ?=
 FOOBAR = ${FOO:=bar}
@@ -54,3 +54,10 @@
 ampersand:
        @echo ${:U${a.bcd.e:L:a.%=%}:Q}
        @echo ${:U${a.bcd.e:L:a.%=&}:Q}
+
+# Before 2020-07-20, when a SysV modifier was parsed, a single dollar
+# before the '=' was interpreted as an anchor, which doesn't make sense
+# since the anchor was discarded immediately.
+anchor-dollar:
+       @echo $@: ${:U${value:L:e$=x}:Q}
+       @echo $@: ${:U${value:L:e=x}:Q}