e2e test to check parameters validation

Signed-off-by: Nicolas De Loof <nicolas.deloof@gmail.com>

e2e/testdata/invalid/unused_parameter.dockerapp/docker-compose.yml

@@ -0,0 +1,29 @@
+version: "3.6"
+services:
+  api:
+    image: python:3.6
+    networks:
+      back:
+      front:
+        aliases:
+          - api.example.com
+          - ${api.host}
+  web:
+    image: nginx:latest
+    networks:
+      - front
+    volumes:
+      - static:/opt/${static_subdir}
+    ports:
+      - ${web.port}:80
+  db:
+    image: postgres:9.3
+    networks:
+      - back
+networks:
+  front:
+  back:
+volumes:
+  static:
+    external: true
+    name: corp/web-static-data

e2e/testdata/invalid/unused_parameter.dockerapp/metadata.yml

@@ -0,0 +1,8 @@
+version: 1.1.0-beta1
+name: simple
+description: "new fancy webapp with microservices"
+maintainers:
+  - name: John Developer
+    email: john.dev@example.com
+  - name: Jane Developer
+    email: jane.dev@example.com

e2e/testdata/invalid/unused_parameter.dockerapp/parameters.yml

@@ -0,0 +1,7 @@
+web:
+  port: '8082'
+api:
+  host: example.com
+static_subdir: data/static
+unused:
+  parameter: FOO

e2e/validate_test.go

@@ -0,0 +1,19 @@
+package e2e
+
+import (
+	"path"
+	"testing"
+
+	"gotest.tools/assert"
+
+	"gotest.tools/icmd"
+)
+
+func TestOrphanedParameter(t *testing.T) {
+	cmd, cleanup := dockerCli.createTestCmd()
+	defer cleanup()
+	p := path.Join("testdata", "invalid", "unused_parameter")
+	cmd.Command = dockerCli.Command("app", "validate", p)
+	out := icmd.RunCmd(cmd).Assert(t, icmd.Expected{ExitCode: 1}).Combined()
+	assert.Equal(t, out, "unused.parameter is declared as parameter but not used by the compose file")
+}