Add tests for override and document

README.md

@@ -88,6 +88,31 @@ You can specify arguments to specify loading environment in same manner with exe
 
 ## Advanced Usage
 
+### Overriding environment variable
+
+`zenv` can override environment variable by multiple `-e` option.
+
+```sh
+$ cat .env
+POSTGRES_DB=your_local_db
+POSTGRES_USER=test_user
+$ cat .env.local
+POSTGRES_DB=your_local_dev_db
+$ zenv -e .env -e .env.local psql
+# Access to your_local_dev_db with test_user
+```
+
+The priority for loading environment variables is as follows: first, the `-e` option, followed by additional `-e` options, and finally, the arguments of the `zenv` command.
+
+```sh
+$ cat .env1
+COLOR=blue
+$ cat .env2
+COLOR=orange
+$ zenv -e .env1 -e .env2 COLOR=red echo %COLOR
+red
+```
+
 ### Generate random secure value
 
 `secret generate` subcommand can generate random value like token and save to KeyChain.

go.mod

@@ -7,15 +7,15 @@ require (
 	github.com/google/uuid v1.3.0
 	github.com/keybase/go-keychain v0.0.0-20221221221913-9be78f6c498b
 	github.com/m-mizutani/goerr v0.1.8
-	github.com/m-mizutani/gt v0.0.4-0.20230223020823-2e7042cd92a6
+	github.com/m-mizutani/gt v0.0.10
 	github.com/mattn/go-shellwords v1.0.12
 	github.com/rs/zerolog v1.29.0
 	github.com/urfave/cli/v2 v2.24.4
 )
 
 require (
 	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
-	github.com/google/go-cmp v0.5.9 // indirect
+	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.17 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect

go.sum

@@ -4,16 +4,16 @@ github.com/coreos/go-systemd/v22 v22.3.3-0.20220203105225-a9a7ef127534/go.mod h1
 github.com/cpuguy83/go-md2man/v2 v2.0.2 h1:p1EgwI/C7NhT0JmVkwCD2ZBK8j4aeHQX2pMHHBfMQ6w=
 github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
 github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
-github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
-github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/keybase/go-keychain v0.0.0-20221221221913-9be78f6c498b h1:k2ZvAPXrDB1Q7fGRdUane+T08K+UaL96qH47Setr/7k=
 github.com/keybase/go-keychain v0.0.0-20221221221913-9be78f6c498b/go.mod h1:TXh6wFVZNh4iuqbymzy4r3obmj8hTPDlLNnoKNIbvJE=
 github.com/m-mizutani/goerr v0.1.8 h1:6UtsMmOkJsaYNtAsMNLvWIteZPl1NOxpKFYK5m65vpQ=
 github.com/m-mizutani/goerr v0.1.8/go.mod h1:fQkXuu06q+oLlp4FkbiTFzI/N/+WAK/Mz1W5kPZ6yzs=
-github.com/m-mizutani/gt v0.0.4-0.20230223020823-2e7042cd92a6 h1:aB3qT7U3VGuzOyoz/6QbwE7DxbrFWQBLlbOYwjSSBss=
-github.com/m-mizutani/gt v0.0.4-0.20230223020823-2e7042cd92a6/go.mod h1:0MPYSfGBLmYjTduzADVmIqD58ELQ5IfBFiK/f0FmB3k=
+github.com/m-mizutani/gt v0.0.10 h1:gJsRcZ0R0kcVAGeahwDAVBCDCwOA/tFw3N1/kh3DnAY=
+github.com/m-mizutani/gt v0.0.10/go.mod h1:0MPYSfGBLmYjTduzADVmIqD58ELQ5IfBFiK/f0FmB3k=
 github.com/mattn/go-colorable v0.1.12/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
 github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=

pkg/usecase/common.go

@@ -124,6 +124,16 @@ func (x *Usecase) parseArgs(args types.Arguments) (types.Arguments, []*model.Env
 		}
 	}
 
+	// Remove duplicated env vars. The last one is used.
+	unique := make(map[types.EnvKey]*model.EnvVar)
+	for _, v := range envVars {
+		unique[v.Key] = v
+	}
+	envVars = make([]*model.EnvVar, 0, len(unique))
+	for _, v := range unique {
+		envVars = append(envVars, v)
+	}
+
 	assigned := make([]*model.EnvVar, len(envVars))
 	for i, v := range envVars {
 		newVar := *v

pkg/usecase/exec_test.go

@@ -2,6 +2,8 @@ package usecase_test
 
 import (
 	"fmt"
+	"os"
+	"sort"
 	"testing"
 
 	"github.com/m-mizutani/gt"
@@ -82,6 +84,9 @@ func TestDotEnv(t *testing.T) {
 			gt.Array(t, args).
 				Equal([]types.Argument{"this", "test"})
 
+			sort.Slice(vars, func(i, j int) bool {
+				return vars[i].Key < vars[j].Key
+			})
 			gt.Array(t, vars).Equal([]*model.EnvVar{
 				{
 					Key:   "COLOR",
@@ -163,3 +168,88 @@ func TestReplacement(t *testing.T) {
 		}))
 	})
 }
+
+func TestOverride(t *testing.T) {
+	type testCase struct {
+		inputFiles []types.FilePath
+		envVars    []*model.EnvVar
+	}
+
+	runTest := func(tc testCase) func(t *testing.T) {
+		return func(t *testing.T) {
+			var called int
+			uc, mock := usecase.NewWithMock(usecase.WithConfig(&model.Config{
+				DotEnvFiles: tc.inputFiles,
+			}))
+			mock.ReadFileMock = func(filename types.FilePath) ([]byte, error) {
+				return os.ReadFile(string(filename))
+			}
+
+			mock.ExecMock = func(vars []*model.EnvVar, args types.Arguments) error {
+				called++
+
+				sort.Slice(vars, func(i, j int) bool {
+					return vars[i].Key < vars[j].Key
+				})
+
+				gt.Array(t, vars).Equal(tc.envVars)
+				return nil
+			}
+
+			gt.NoError(t, uc.Exec(&model.ExecInput{
+				Args: types.Arguments{"this", "test"},
+			}))
+			gt.Equal(t, called, 1)
+		}
+	}
+
+	t.Run("no override env vars", runTest(testCase{
+		inputFiles: []types.FilePath{"testdata/basic.env"},
+		envVars: []*model.EnvVar{
+			{Key: "COLOR", Value: "blue"},
+		},
+	}))
+
+	t.Run("override env vars by one file", runTest(testCase{
+		inputFiles: []types.FilePath{
+			"testdata/basic.env",
+			"testdata/override1.env",
+		},
+		envVars: []*model.EnvVar{
+			{Key: "COLOR", Value: "orange"},
+		},
+	}))
+
+	t.Run("override env vars by two files", runTest(testCase{
+		inputFiles: []types.FilePath{
+			"testdata/basic.env",
+			"testdata/override1.env",
+			"testdata/override2.env",
+		},
+		envVars: []*model.EnvVar{
+			{Key: "COLOR", Value: "red"},
+		},
+	}))
+
+	t.Run("override env vars prioritize by order", runTest(testCase{
+		inputFiles: []types.FilePath{
+			"testdata/basic.env",
+			"testdata/override2.env",
+			"testdata/override1.env",
+		},
+		envVars: []*model.EnvVar{
+			{Key: "COLOR", Value: "orange"},
+		},
+	}))
+
+	t.Run("override env vars prioritize by order (2)", runTest(testCase{
+		inputFiles: []types.FilePath{
+			"testdata/override2.env",
+			"testdata/override1.env",
+			"testdata/basic.env",
+		},
+		envVars: []*model.EnvVar{
+			{Key: "COLOR", Value: "blue"},
+		},
+	}))
+}

pkg/usecase/testdata/basic.env

@@ -0,0 +1 @@
+COLOR=blue

pkg/usecase/testdata/override1.env

@@ -0,0 +1 @@
+COLOR=orange

pkg/usecase/testdata/override2.env

@@ -0,0 +1 @@
+COLOR=red

pkg/usecase/usecase_test.go

@@ -53,7 +53,7 @@ func TestGenerate(t *testing.T) {
 		mock.PutKeyChainValuesMock = func(envVars []*model.EnvVar, namespace types.Namespace) error {
 			gt.V(t, namespace).Equal("zenv.bridge")
 			gt.A(t, envVars).Length(1).
-				Elem(0, func(t testing.TB, v *model.EnvVar) {
+				At(0, func(t testing.TB, v *model.EnvVar) {
 					gt.Value(t, v.Key).Equal("SECRET")
 					gt.N(t, len(v.Value)).Equal(24)
 				})