A .env file in the working directory is now optional

internal/cli/flags_test.go

@@ -73,11 +73,17 @@ func TestConfigFlag(t *testing.T) {
 	}
 }
 
-func TestMissingEnvFile(t *testing.T) {
+// A .env file is optional, but one that can't be parsed is an error.
+func TestEnvFile(t *testing.T) {
 	cmdtest.Setup(t, appConfig)
 	if err := os.Remove(".env"); err != nil {
 		t.Fatal(err)
 	}
+	if _, err := cmdtest.Run(t, newRoot, "", "level"); err != nil {
+		t.Errorf("without a .env file: %v; want no error", err)
+	}
+
+	cmdtest.WriteFile(t, ".env", "NOT VALID\n")
 	_, err := cmdtest.Run(t, newRoot, "", "level")
 	cmdtest.ErrContains(t, err, ".env")
 }

internal/config/README.md

@@ -8,8 +8,8 @@ environment variables, merged through [Viper](https://github.com/spf13/viper).
 ## Loading order
 `Init(cfgFile, &conf)` builds the configuration in this order:
 
-1. Loads `.env` from the working directory into the environment. A missing
-   `.env` file is an error.
+1. Loads `.env` from the working directory into the environment, if there
+   is one. A `.env` file that can't be read or parsed is an error.
 2. Sets the defaults from the `default` struct tags as Viper defaults.
 3. Reads the config file: `cfgFile` if given, otherwise the first
    `config.yaml` found in `/etc/job-search` then the working directory. If no

internal/config/load.go

@@ -3,6 +3,7 @@ package config
 import (
 	"errors"
 	"fmt"
+	"io/fs"
 	"log/slog"
 	"os"
 	"strings"
@@ -34,9 +35,13 @@ func isExplicitlySet(key string) bool {
 }
 
 // loadEnv loads environment variables from a .env file in the working
-// directory.
+// directory, if there is one. One that can't be read or parsed is an error.
 func loadEnv() error {
-	if err := godotenv.Load(); err != nil {
+	err := godotenv.Load()
+	if errors.Is(err, fs.ErrNotExist) {
+		return nil
+	}
+	if err != nil {
 		return fmt.Errorf("invalid .env file: %w", err)
 	}
 	return nil

internal/config/load_test.go

@@ -141,9 +141,19 @@ func TestInitKeepsCommandLineLevel(t *testing.T) {
 	}
 }
 
+// A .env file is optional.
+func TestInitWithoutEnvFile(t *testing.T) {
+	initDir(t, nil, testConfigYAML)
+	var conf JobSearchConfig
+	if err := Init("", &conf); err != nil {
+		t.Fatalf("err = %v; want nil without a .env file", err)
+	}
+}
+
 func TestInitErrors(t *testing.T) {
-	t.Run("no .env file", func(t *testing.T) {
-		initDir(t, nil, testConfigYAML)
+	t.Run("invalid .env file", func(t *testing.T) {
+		dir := initDir(t, nil, testConfigYAML)
+		writeFile(t, filepath.Join(dir, ".env"), "NOT VALID\n")
 		var conf JobSearchConfig
 		if err := Init("", &conf); err == nil ||
 			!strings.Contains(err.Error(), ".env") {