use As to unwrap errors in Cast

studio-b12 · Aug 1, 2024 · 0a6bb5c · 0a6bb5c
1 parent 2c9574b
commit 0a6bb5c
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Showing 2 changed files with 45 additions and 8 deletions.
diff --git a/error.go b/error.go
@@ -79,10 +79,10 @@ func Cast(err error, fallback ...ErrorCode) Error {
 		}
 
 		var lastElkErr *Error
-		for _, err := range errs {
-			if elkErr, ok := err.(Error); ok {
+		for _, innerErr := range errs {
+			if elkErr, ok := As[Error](innerErr); ok {
 				if lastElkErr != nil {
-					return Wrap(code, err)
+					return Wrap(code, innerErr)
 				}
 				lastElkErr = &elkErr
 			}
@@ -95,7 +95,7 @@ func Cast(err error, fallback ...ErrorCode) Error {
 		return *lastElkErr
 	}
 
-	d, ok := err.(Error)
+	d, ok := As[Error](err)
 	if !ok {
 		d = Wrap(code, err)
 		d.callStack.offset++

diff --git a/error_test.go b/error_test.go
@@ -10,7 +10,7 @@ import (
 func TestCast(t *testing.T) {
 	const ErrCode = ErrorCode("some-error-code")
 
-	t.Run("cast-Error", func(t *testing.T) {
+	t.Run("error", func(t *testing.T) {
 		err := errors.New("some error")
 		wrappedErr := Wrap(ErrCode, err)
 		castError := Cast(wrappedErr)
@@ -19,23 +19,23 @@ func TestCast(t *testing.T) {
 		assert.Equal(t, err, castError.Unwrap())
 	})
 
-	t.Run("cast-error-default", func(t *testing.T) {
+	t.Run("error-default", func(t *testing.T) {
 		err := errors.New("some error")
 		castError := Cast(err)
 
 		assert.Equal(t, castError.Code(), CodeUnexpected)
 		assert.Equal(t, err, castError.Unwrap())
 	})
 
-	t.Run("cast-error-custom", func(t *testing.T) {
+	t.Run("error-custom", func(t *testing.T) {
 		err := errors.New("some error")
 		castError := Cast(err, ErrCode)
 
 		assert.Equal(t, castError.Code(), ErrCode)
 		assert.Equal(t, err, castError.Unwrap())
 	})
 
-	t.Run("cast-error-join", func(t *testing.T) {
+	t.Run("error-join", func(t *testing.T) {
 		err := errors.Join(nil)
 		castError := Cast(err, ErrCode)
 		assert.Equal(t, castError.Code(), ErrCode)
@@ -55,4 +55,41 @@ func TestCast(t *testing.T) {
 		castError = Cast(err, ErrCode)
 		assert.Equal(t, castError.Code(), ErrCode)
 	})
+
+	t.Run("custom-model", func(t *testing.T) {
+		errCode := ErrorCode("custom-code")
+
+		type MyError struct {
+			InnerError
+			SomeData string
+		}
+
+		err := MyError{
+			InnerError: InnerError{Inner: NewError(errCode, "some message")},
+			SomeData:   "some data",
+		}
+
+		castErrCode := Cast(err).Code()
+		assert.Equal(t, errCode, castErrCode)
+	})
+
+	t.Run("custom-model-wrapped", func(t *testing.T) {
+		errCode := ErrorCode("custom-code")
+		wrappedErrCode := ErrorCode("wrapped-custom-code")
+
+		type MyError struct {
+			InnerError
+			SomeData string
+		}
+
+		wrappedErr := NewError(wrappedErrCode, "some message")
+
+		err := MyError{
+			InnerError: InnerError{Inner: Wrap(errCode, wrappedErr)},
+			SomeData:   "some data",
+		}
+
+		castErrCode := Cast(err).Code()
+		assert.Equal(t, errCode, castErrCode)
+	})
 }