Add a unit-test for comments.

Addition to PR bin/17732.
Approved by sjg and christos.

usr.bin/make/unit-tests/Makefile

@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.15 2005/06/01 17:17:34 sjg Exp $
+# $NetBSD: Makefile,v 1.16 2005/06/15 22:32:22 rpaulo Exp $
 #
 # Unit tests for make(1)
 # The main targets are:
@@ -19,6 +19,7 @@ UNIT_TESTS:= ${.PARSEDIR}
 # Simple sub-makefiles - we run them as a black box
 # keep the list sorted.
 SUBFILES= \
+	comment \
 	cond1 \
 	modmatch \
 	modorder \

usr.bin/make/unit-tests/comment

@@ -0,0 +1,23 @@
+# This is a comment
+.if ${MACHINE_ARCH} == something
+FOO=bar
+.endif
+
+#\
+	Multiline comment
+
+# This is an escaped comment \
+that keeps going until the end of this line
+
+# Another escaped comment \
+that \
+goes \
+on
+
+# This is NOT an escaped comment due to the double backslashes \\
+all: foo
+	@echo comment testing done
+
+foo:
+	@echo this is $@
+