test: Add an e2e test for the COMPOSE_FILE environment variable in fi…

option/option.go

@@ -6,8 +6,10 @@ package option
 
 import (
 	"errors"
+	"fmt"
 	"os"
 	"os/exec"
+	"strings"
 )
 
 // Option customizes how tests are run.
@@ -50,3 +52,31 @@ func (o *Option) NewCmd(args ...string) *exec.Cmd {
 	cmd.Env = append(os.Environ(), o.env...)
 	return cmd
 }
+
+// UpdateEnv updates the environment variable for the key name of the input.
+func (o *Option) UpdateEnv(envKey, envValue string) {
+	env := fmt.Sprintf("%s=%s", envKey, envValue)
+	if i, exists := containsEnv(o.env, envKey); exists {
+		o.env[i] = env
+	} else {
+		o.env = append(o.env, env)
+	}
+}
+
+// DeleteEnv deletes the environment variable for the key name of the input.
+func (o *Option) DeleteEnv(envKey string) {
+	if i, exists := containsEnv(o.env, envKey); exists {
+		o.env = append(o.env[:i], o.env[i+1:]...)
+	}
+}
+
+// containsEnv determines whether an environment variable exists.
+func containsEnv(envs []string, targetEnvKey string) (int, bool) {
+	for i, env := range envs {
+		if strings.Split(env, "=")[0] == targetEnvKey {
+			return i, true
+		}
+	}
+
+	return -1, false
+}

tests/compose_build.go

@@ -44,6 +44,22 @@ func ComposeBuild(o *option.Option) {
 			gomega.Expect(output).Should(gomega.Equal("Compose build test"))
 		})
 
+		ginkgo.It("should build services defined in the compose file specified by the COMPOSE_FILE environment variable", func() {
+			envKey := "COMPOSE_FILE"
+			o.UpdateEnv(envKey, composeFilePath)
+
+			command.Run(o, "compose", "build")
+
+			imageList := command.GetAllImageNames(o)
+			gomega.Expect(imageList).Should(gomega.ContainElement(gomega.HaveSuffix(imageSuffix[0])))
+			gomega.Expect(imageList).Should(gomega.ContainElement(gomega.HaveSuffix(imageSuffix[1])))
+			// The built image should print 'Compose build test' when run.
+			output := command.StdoutStr(o, "run", localImages[defaultImage])
+			gomega.Expect(output).Should(gomega.Equal("Compose build test"))
+
+			o.DeleteEnv(envKey)
+		})
+
 		ginkgo.It("should output progress in plain text format", func() {
 			composeBuildOutput := command.StderrStr(o, "compose", "build", "--progress",
 				"plain", "--no-cache", "--file", composeFilePath)