One plugin per dir.

plugin/someteam.example.com/v1/sedtransformer/SedTransformer_test.go

@@ -0,0 +1,52 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package main_test
+
+import (
+	"testing"
+
+	"sigs.k8s.io/kustomize/pkg/kusttest"
+	"sigs.k8s.io/kustomize/plugin"
+)
+
+func TestSedTransformer(t *testing.T) {
+	tc := plugin.NewEnvForTest(t).Set()
+	defer tc.Reset()
+
+	tc.BuildExecPlugin("someteam.example.com", "v1", "SedTransformer")
+	th := kusttest_test.NewKustTestPluginHarness(t, "/app")
+
+	th.WriteF("/app/sed-input.txt", `
+s/$FRUIT/orange/g
+s/$VEGGIE/tomato/g
+`)
+
+	rm := th.LoadAndRunTransformer(`
+apiVersion: someteam.example.com/v1
+kind: SedTransformer
+metadata:
+  name: notImportantHere
+argsOneLiner: s/one/two/g
+argsFromFile: sed-input.txt
+`,
+		`apiVersion: apps/v1
+kind: MeatBall
+metadata:
+  name: notImportantHere
+beans: one one one one
+fruit: $FRUIT
+vegetable: $VEGGIE
+`)
+
+	th.AssertActualEqualsExpected(rm, `
+apiVersion: apps/v1
+beans: two two two two
+fruit: orange
+kind: MeatBall
+metadata:
+  annotations: {}
+  name: notImportantHere
+vegetable: tomato
+`)
+}