1 files changed, 105 insertions, 0 deletions
diff --git a/contrib/bmake/unit-tests/varname-dot-suffixes.mk b/contrib/bmake/unit-tests/varname-dot-suffixes.mk
new file mode 100644
index 000000000000..27521f621cb0
--- /dev/null
+++ b/contrib/bmake/unit-tests/varname-dot-suffixes.mk
@@ -0,0 +1,105 @@
+# $NetBSD: varname-dot-suffixes.mk,v 1.5 2023/12/20 09:03:09 rillig Exp $
+#
+# Tests for the special "variable" .SUFFIXES, which lists the suffixes that
+# have been registered for use in suffix transformation rules.  Suffixes are
+# listed even if there is no actual transformation rule that uses them.
+#
+# The name '.SUFFIXES' does not refer to a real variable, instead it can be
+# used as a starting "variable name" for expressions like ${.SUFFIXES} or
+# ${.SUFFIXES:M*o}.
+
+# In the beginning, there are no suffix rules, the expression is thus empty.
+.if ${.SUFFIXES} != ""
+.endif
+
+# There is no actual variable named '.SUFFIXES', it is all made up.
+.if defined(.SUFFIXES)
+.  error
+.endif
+
+# The suffixes list is still empty, and so is the "variable" '.SUFFIXES'.
+.if !empty(.SUFFIXES)
+.  error
+.endif
+
+.SUFFIXES: .c .o .1		.err
+
+# The suffixes are listed in declaration order.
+.if ${.SUFFIXES} != ".c .o .1 .err"
+.  error
+.endif
+
+# There is still no actual variable named '.SUFFIXES', it is all made up.
+.if defined(.SUFFIXES)
+.  error
+.endif
+
+# Now the suffixes list is not empty anymore.  It may seem strange that there
+# is no variable named '.SUFFIXES' but evaluating '${.SUFFIXES}' nevertheless
+# returns something.  For all practical use cases, it's good enough though.
+.if empty(.SUFFIXES)
+.  error
+.endif
+
+.SUFFIXES: .tar.gz
+
+# Changes to the suffixes list are reflected immediately.
+.if ${.SUFFIXES} != ".c .o .1 .err .tar.gz"
+.  error
+.endif
+
+# Deleting .SUFFIXES has no effect since there is no actual variable of that
+# name.
+.MAKEFLAGS: -dv
+# expect: Global: ignoring delete '.SUFFIXES' as it is not found
+.undef .SUFFIXES
+.MAKEFLAGS: -d0
+.if ${.SUFFIXES} != ".c .o .1 .err .tar.gz"
+.  error
+.endif
+
+# The list of suffixes can only be modified using dependency declarations, any
+# attempt at setting the variable named '.SUFFIXES' is rejected.
+.MAKEFLAGS: -dv
+# expect: Global: ignoring '.SUFFIXES = set' as it is read-only
+.SUFFIXES=	set
+# expect: Global: ignoring '.SUFFIXES = append' as it is read-only
+.SUFFIXES+=	append
+# expect: Global: ignoring '.SUFFIXES = assign' as it is read-only
+_:=		${.SUFFIXES::=assign}
+# expect: Global: ignoring '.SUFFIXES = preserve' as it is read-only
+_:=		${preserve:L:_=.SUFFIXES}
+.MAKEFLAGS: -d0
+
+# Using the name '.SUFFIXES' in a .for loop looks strange because these
+# variable names are typically in singular form, and .for loops do not use
+# real variables either, they are made up as well, see directive-for.mk.  The
+# replacement mechanism for the iteration variables takes precedence.
+.for .SUFFIXES in .c .o
+.  if ${.SUFFIXES} != ".c" && ${.SUFFIXES} != ".o"
+.    error
+.  endif
+.endfor
+
+# After the .for loop, the expression '${.SUFFIXES}' refers to the list of
+# suffixes again.
+.if ${.SUFFIXES} != ".c .o .1 .err .tar.gz"
+.  error
+.endif
+
+# Using the name '.SUFFIXES' in the modifier ':@var@body@' does not create an
+# actual variable either.  Like in the .for loop, choosing the name
+# '.SUFFIXES' for the iteration variable is unusual.  In ODE Make, the
+# convention for these iteration variables is to have dots at both ends, so
+# the name would be '.SUFFIXES.', furthermore the name of the iteration
+# variable is typically in singular form.
+.MAKEFLAGS: -dv
+# expect: Command: ignoring '.SUFFIXES = 1' as it is read-only
+# expect: Command: ignoring '.SUFFIXES = 2' as it is read-only
+# expect: Command: ignoring delete '.SUFFIXES' as it is not found
+.if ${1 2:L:@.SUFFIXES@${.SUFFIXES}@} != ".c .o .1 .err .tar.gz .c .o .1 .err .tar.gz"
+.  error
+.endif
+.MAKEFLAGS: -d0
+
+all: