1 files changed, 44 insertions, 11 deletions
diff --git a/unit-tests/varmod-match.mk b/unit-tests/varmod-match.mk
index 805426a0fda9..5e16a9cc8bf1 100644
--- a/unit-tests/varmod-match.mk
+++ b/unit-tests/varmod-match.mk
@@ -1,22 +1,55 @@
-# $NetBSD: varmod-match.mk,v 1.3 2020/08/16 20:03:53 rillig Exp $
+# $NetBSD: varmod-match.mk,v 1.5 2020/09/13 05:36:26 rillig Exp $
 #
 # Tests for the :M variable modifier, which filters words that match the
 # given pattern.
+#
+# See ApplyModifier_Match and ModifyWord_Match for the implementation.
 
-all: match-char-class
-all: slow
-
+.MAKEFLAGS: -dc
 
 NUMBERS=	One Two Three Four five six seven
 
-match-char-class:
-	@echo '$@:'
-	@echo '  uppercase numbers: ${NUMBERS:M[A-Z]*}'
-	@echo '  all the others: ${NUMBERS:M[^A-Z]*}'
-	@echo '  starts with non-s, ends with [ex]: ${NUMBERS:M[^s]*[ex]}'
+# Only keep words that start with an uppercase letter.
+.if ${NUMBERS:M[A-Z]*} != "One Two Three Four"
+.  error
+.endif
 
+# Only keep words that start with a character other than an uppercase letter.
+.if ${NUMBERS:M[^A-Z]*} != "five six seven"
+.  error
+.endif
+
+# Only keep words that don't start with s and at the same time end with
+# either of [ex].
+#
+# This test case ensures that the negation from the first character class
+# does not propagate to the second character class.
+.if ${NUMBERS:M[^s]*[ex]} != "One Three five"
+.  error
+.endif
 
 # Before 2020-06-13, this expression took quite a long time in Str_Match,
 # calling itself 601080390 times for 16 asterisks.
-slow:
-	@: ${:U****************:M****************b}
+.if ${:U****************:M****************b}
+.endif
+
+# To match a dollar sign in a word, double it.
+#
+# This is different from the :S and :C variable modifiers, where a '$'
+# has to be escaped as '\$'.
+.if ${:Ua \$ sign:M*$$*} != "\$"
+.  error
+.endif
+
+# In the :M modifier, '\$' does not escape a dollar.  Instead it is
+# interpreted as a backslash followed by whatever expression the
+# '$' starts.
+#
+# This differs from the :S, :C and several other variable modifiers.
+${:U*}=		asterisk
+.if ${:Ua \$ sign any-asterisk:M*\$*} != "any-asterisk"
+.  error
+.endif
+
+all:
+	@:;