feat: add more tests for env

Author: roman-vanesyan

env/env_test.go

@@ -3,46 +3,86 @@ package env
 import (
 	"os"
 	"testing"
+
+	"github.com/go-playground/validator/v10"
 )
 
+type Config struct {
+	Config1 string `env:"CONFIG1"`
+	Config2 int    `env:"CONFIG2"`
+	Config3 string `env:"CONFIG3"`
+}
+
 func TestLoad(t *testing.T) {
-	// Make sure that the environment variables are not set.
-	os.Clearenv()
 
-	t.Setenv("CONFIG1", "value1")
+	t.Run("missing value", func(t *testing.T) {
+		// Make sure that the environment variables are not set.
+		os.Clearenv()
 
-	type Config struct {
-		Config1 string `env:"CONFIG1"`
-		Config2 int    `env:"CONFIG2"`
-	}
+		cfg, err := Load[Config]()
+		if err != nil {
+			t.Fatal(err)
+		}
 
-	cfg, err := Load[Config]("fixtures/test.env")
-	if err != nil {
-		t.Fatal(err)
-	}
+		validate(t, "CONFIG1", "", cfg.Config1)
+		validate(t, "CONFIG2", 0, cfg.Config2)
+	})
 
-	validate(t, "CONFIG1", "value1", cfg.Config1)
-	validate(t, "CONFIG2", 2, cfg.Config2)
-}
+	t.Run("load from env and file", func(t *testing.T) {
+		// Make sure that the environment variables are not set.
+		os.Clearenv()
 
-func TestLoadMissingConfigFile(t *testing.T) {
-	// Make sure that the environment variables are not set.
-	os.Clearenv()
+		t.Setenv("CONFIG1", "value1")
 
-	t.Setenv("CONFIG1", "value1")
+		cfg, err := Load[Config]("fixtures/test.env")
+		if err != nil {
+			t.Fatal(err)
+		}
 
-	type Config struct {
-		Config1 string `env:"CONFIG1"`
-		Config2 string `env:"CONFIG2"`
-	}
+		validate(t, "CONFIG1", "value1", cfg.Config1)
+		validate(t, "CONFIG2", 2, cfg.Config2)
+	})
 
-	cfg, err := Load[Config]("fixtures/missing.env")
-	if err != nil {
-		t.Fatal(err)
-	}
+	t.Run("env variables take precedence over file", func(t *testing.T) {
+		// Make sure that the environment variables are not set.
+		os.Clearenv()
+
+		t.Setenv("CONFIG2", "7")
+
+		cfg, err := Load[Config]("fixtures/test.env")
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		validate(t, "CONFIG2", 7, cfg.Config2)
+		validate(t, "CONFIG3", "value3", cfg.Config3)
+	})
+
+	t.Run("it fails on validation", func(t *testing.T) {
+		// Make sure that the environment variables are not set.
+		os.Clearenv()
+
+		t.Setenv("NON_ZERO_FLOAT", "1")
+
+		type Config struct {
+			NonZeroFoat    float32 `env:"NON_ZERO_FLOAT"   validate:"required"`
+			NonEmptyString string  `env:"NON_EMPTY_STRING" validate:"required"`
+			NonZeroInt     int     `env:"NON_ZERO_INT"     validate:"required"`
+		}
+
+		_, err := Load[Config]()
+		if err == nil {
+			t.Fatal("expected error")
+		}
+
+		errs := err.(validator.ValidationErrors)
+		if len(errs) != 2 {
+			t.Fatalf("expected 2 errors, got %d", len(errs))
+		}
 
-	validate(t, "CONFIG1", "value1", cfg.Config1)
-	validate(t, "CONFIG2", "", cfg.Config2)
+		validate(t, "NON_ZERO_INT", "Config.NonEmptyString", errs[0].StructNamespace())
+		validate(t, "NON_EMPTY_STRING", "Config.NonZeroInt", errs[1].StructNamespace())
+	})
 }
 
 func validate[T comparable](t *testing.T, key string, expected T, got T) {

env/fixtures/test.env

@@ -1 +1,2 @@
 CONFIG2="2"
+CONFIG3="value3"

must/must.go

@@ -1,3 +1,4 @@
+// Package must provides a convenient way to panic on errors.
 package must
 
 // Must1 panics if err is not nil.