add test to catch this case

builder/amazon/common/build_filter_test.go

@@ -0,0 +1,31 @@
+package common
+
+import (
+	"testing"
+)
+
+func TestStepSourceAmiInfo_BuildFilter(t *testing.T) {
+	filter_key := "name"
+	filter_value := "foo"
+	filter_key2 := "name2"
+	filter_value2 := "foo2"
+
+	inputFilter := map[string]string{filter_key: filter_value, filter_key2: filter_value2}
+	outputFilter := buildEc2Filters(inputFilter)
+
+	// deconstruct filter back into things we can test
+	foundMap := map[string]bool{filter_key: false, filter_key2: false}
+	for _, filter := range outputFilter {
+		for key, value := range inputFilter {
+			if *filter.Name == key && *filter.Values[0] == value {
+				foundMap[key] = true
+			}
+		}
+	}
+
+	for k, v := range foundMap {
+		if !v {
+			t.Fatalf("Fail: should have found value for key: %s", k)
+		}
+	}
+}