feat: Set table name based on flag or environment variable

README.md

@@ -247,6 +247,7 @@ arguments, you can set the following environment variables:
 export GOOSE_DRIVER=DRIVER
 export GOOSE_DBSTRING=DBSTRING
 export GOOSE_MIGRATION_DIR=MIGRATION_DIR
+export GOOSE_TABLE=TABLENAME
 ```
 
 **2. Via `.env` files with corresponding variables. `.env` file example**:
@@ -255,6 +256,7 @@ export GOOSE_MIGRATION_DIR=MIGRATION_DIR
 GOOSE_DRIVER=postgres
 GOOSE_DBSTRING=postgres://admin:admin@localhost:5432/admin_db
 GOOSE_MIGRATION_DIR=./migrations
+GOOSE_TABLE=custom.goose_migrations
 ```
 
 Loading from `.env` files is enabled by default. To disable this feature, set the `-env=none` flag.

cmd/goose/main.go

@@ -28,7 +28,7 @@ var (
 
 	flags        = flag.NewFlagSet("goose", flag.ExitOnError)
 	dir          = flags.String("dir", DefaultMigrationDir, "directory with migration files, (GOOSE_MIGRATION_DIR env variable supported)")
-	table        = flags.String("table", "goose_db_version", "migrations table name")
+	table        = flags.String("table", "", "migrations table name")
 	verbose      = flags.Bool("v", false, "enable verbose mode")
 	help         = flags.Bool("h", false, "print help")
 	versionFlag  = flags.Bool("version", false, "print version")
@@ -83,7 +83,9 @@ func main() {
 	if *sequential {
 		goose.SetSequential(true)
 	}
-	goose.SetTableName(*table)
+
+	// The order of precedence should be: flag > env variable > default value.
+	goose.SetTableName(firstNonEmpty(*table, envConfig.table, goose.DefaultTablename))
 
 	args := flags.Args()
 
@@ -421,6 +423,7 @@ type envConfig struct {
 	driver   string
 	dbstring string
 	dir      string
+	table    string
 	noColor  bool
 }
 
@@ -429,6 +432,7 @@ func loadEnvConfig() *envConfig {
 	return &envConfig{
 		driver:   envOr("GOOSE_DRIVER", ""),
 		dbstring: envOr("GOOSE_DBSTRING", ""),
+		table:    envOr("GOOSE_TABLE", ""),
 		dir:      envOr("GOOSE_MIGRATION_DIR", DefaultMigrationDir),
 		// https://no-color.org/
 		noColor: noColorBool,
@@ -440,6 +444,7 @@ func (c *envConfig) listEnvs() []envVar {
 		{Name: "GOOSE_DRIVER", Value: c.driver},
 		{Name: "GOOSE_DBSTRING", Value: c.dbstring},
 		{Name: "GOOSE_MIGRATION_DIR", Value: c.dir},
+		{Name: "GOOSE_TABLE", Value: c.table},
 		{Name: "NO_COLOR", Value: strconv.FormatBool(c.noColor)},
 	}
 }
@@ -457,3 +462,13 @@ func envOr(key, def string) string {
 	}
 	return val
 }
+
+// firstNonEmpty returns the first non-empty string from the provided input or an empty string if all are empty.
+func firstNonEmpty(values ...string) string {
+	for _, v := range values {
+		if v != "" {
+			return v
+		}
+	}
+	return ""
+}

cmd/goose/main_test.go

@@ -0,0 +1,68 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestFirstNonEmpty(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    []string
+		expected string
+	}{
+		{
+			name:     "no values",
+			input:    []string{},
+			expected: "",
+		},
+		{
+			name:     "all empty values",
+			input:    []string{"", "", ""},
+			expected: "",
+		},
+		{
+			name:     "single non-empty value at start",
+			input:    []string{"value", "", ""},
+			expected: "value",
+		},
+		{
+			name:     "single non-empty value in middle",
+			input:    []string{"", "value", ""},
+			expected: "value",
+		},
+		{
+			name:     "single non-empty value at end",
+			input:    []string{"", "", "value"},
+			expected: "value",
+		},
+		{
+			name:     "multiple non-empty values",
+			input:    []string{"first", "second", "third"},
+			expected: "first",
+		},
+		{
+			name:     "mixed empty and non-empty values",
+			input:    []string{"", "value1", "", "value2"},
+			expected: "value1",
+		},
+		{
+			name:     "only one value, empty",
+			input:    []string{""},
+			expected: "",
+		},
+		{
+			name:     "only one value, non-empty",
+			input:    []string{"value"},
+			expected: "value",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := firstNonEmpty(tt.input...)
+			if result != tt.expected {
+				t.Errorf("expected %q, got %q", tt.expected, result)
+			}
+		})
+	}
+}