From f7933685e39a41c3aa6be46b84c9050d91a6198b Mon Sep 17 00:00:00 2001
From: Luiz Ferraz <luiz@lferraz.com>
Date: Mon, 24 Jan 2022 18:21:43 -0300
Subject: [PATCH 1/2] Fix match.As to behave the same as errors.As

---
 match/match.go      |  6 +-----
 match/match_test.go | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/match/match.go b/match/match.go
index eea2f69..72ac7a4 100644
--- a/match/match.go
+++ b/match/match.go
@@ -74,12 +74,8 @@ func As(target interface{}) ErrorMatcher {
 		panic("errors: *target must be interface or implement error")
 	}
 
-	tar := reflect.New(typ).Interface()
-
 	return ErrorMatcherFunc(func(err error) bool {
-		target := tar
-
-		return errors.As(err, &target)
+		return errors.As(err, target)
 	})
 }
 
diff --git a/match/match_test.go b/match/match_test.go
index ed6138c..4a0f5bb 100644
--- a/match/match_test.go
+++ b/match/match_test.go
@@ -2,6 +2,7 @@ package match
 
 import (
 	"errors"
+	"fmt"
 	"testing"
 )
 
@@ -79,6 +80,40 @@ func TestAs(t *testing.T) {
 	}
 }
 
+type errorData struct {
+	data string
+}
+
+func (e errorData) Error() string {
+	return e.data
+}
+
+func TestAs_SetMatchedError(t *testing.T) {
+	var matchErr errorData
+
+	matcher := As(&matchErr)
+
+	matchingErr := fmt.Errorf("wrapping error: %w", errorData{"target data"})
+
+	if !matcher.MatchError(matchingErr) {
+		t.Error("As matcher is not supposed to match an error that cannot be assigned from the error chain")
+	}
+
+	if matchErr.data != "target data" {
+		t.Error("As matcher is supposed to set the matched error to it's value in the chain")
+	}
+}
+
+func TestAs_IncompatibleErrors(t *testing.T) {
+	var matchErr errorData
+
+	matcher := As(&matchErr)
+
+	if matcher.MatchError(errors.New("error")) {
+		t.Error("As matcher is not supposed to match an error that cannot be assigned from the error chain")
+	}
+}
+
 func TestAs_Race(t *testing.T) {
 	var matchErr interface {
 		IsError() bool

From badf1e15edb050d0a30f72f28f94afea22ddf83d Mon Sep 17 00:00:00 2001
From: Luiz Ferraz <luiz@lferraz.com>
Date: Wed, 26 Jan 2022 12:12:04 -0300
Subject: [PATCH 2/2] Replace error wrapping for backward compatibility

---
 match/match_test.go | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/match/match_test.go b/match/match_test.go
index 4a0f5bb..9eca840 100644
--- a/match/match_test.go
+++ b/match/match_test.go
@@ -2,7 +2,6 @@ package match
 
 import (
 	"errors"
-	"fmt"
 	"testing"
 )
 
@@ -88,12 +87,20 @@ func (e errorData) Error() string {
 	return e.data
 }
 
+type wrappingError struct {
+	error
+}
+
+func (w wrappingError) Unwrap() error {
+	return w.error
+}
+
 func TestAs_SetMatchedError(t *testing.T) {
 	var matchErr errorData
 
 	matcher := As(&matchErr)
 
-	matchingErr := fmt.Errorf("wrapping error: %w", errorData{"target data"})
+	matchingErr := wrappingError{error: errorData{"target data"}}
 
 	if !matcher.MatchError(matchingErr) {
 		t.Error("As matcher is not supposed to match an error that cannot be assigned from the error chain")