1 files changed, 40 insertions, 0 deletions
diff --git a/contrib/bmake/unit-tests/export-variants.mk b/contrib/bmake/unit-tests/export-variants.mk
new file mode 100755
index 000000000000..fdbbccccc6c6
--- /dev/null
+++ b/contrib/bmake/unit-tests/export-variants.mk
@@ -0,0 +1,40 @@
+# $NetBSD: export-variants.mk,v 1.4 2020/10/24 08:46:08 rillig Exp $
+#
+# Test whether exported variables apply to each variant of running
+# external commands:
+#
+# The != assignments.
+# The :!cmd! modifier.
+# The :sh modifier.
+
+SHVAR!=	env | grep ^UT_ || true
+.if ${SHVAR} != ""
+.  warning At this point, no variable should be exported.
+.endif
+
+.if ${:!env | grep ^UT_ || true!} != ""
+.  warning At this point, no variable should be exported.
+.endif
+
+.if ${env | grep ^UT_ || true:L:sh} != ""
+.  warning At this point, no variable should be exported.
+.endif
+
+UT_VAR=		value
+.export UT_VAR
+
+SHVAR!=	env | grep ^UT_ || true
+.if ${SHVAR} != "UT_VAR=value"
+.  warning At this point, a single variable should be exported.
+.endif
+
+.if ${:!env | grep ^UT_ || true!} != "UT_VAR=value"
+.  warning At this point, a single variable should be exported.
+.endif
+
+.if ${env | grep ^UT_ || true:L:sh} != "UT_VAR=value"
+.  warning At this point, a single variable should be exported.
+.endif
+
+all:
+	@:;