Add e2e test for random name generation on run

Signed-off-by: Djordje Lukic <djordje.lukic@docker.com>

e2e/run_test.go

@@ -0,0 +1,30 @@
+package e2e
+
+import (
+	"path/filepath"
+	"testing"
+
+	"gotest.tools/icmd"
+)
+
+func TestRunTwice(t *testing.T) {
+	// Test that we are indeed generating random app names
+	// We had a problem where the second run would fail with an error
+	// "Installation "gallant_poitras" already exists, use 'docker app update' instead"
+	runWithDindSwarmAndRegistry(t, func(info dindSwarmAndRegistryInfo) {
+		cmd := info.configuredCmd
+		contextPath := filepath.Join("testdata", "simple")
+
+		cmd.Command = dockerCli.Command("app", "build", "--tag", "myapp1", contextPath)
+		icmd.RunCmd(cmd).Assert(t, icmd.Success)
+
+		cmd.Command = dockerCli.Command("app", "build", "--tag", "myapp2", contextPath)
+		icmd.RunCmd(cmd).Assert(t, icmd.Success)
+
+		cmd.Command = dockerCli.Command("app", "run", "myapp1", "--set", "web_port=8080")
+		icmd.RunCmd(cmd).Assert(t, icmd.Success)
+
+		cmd.Command = dockerCli.Command("app", "run", "myapp2", "--set", "web_port=8081")
+		icmd.RunCmd(cmd).Assert(t, icmd.Success)
+	})
+}