Use the right method to get the expected error type.

Author: ccoVeille

assert/assertions.go

@@ -2217,17 +2217,17 @@ func ErrorAs(t TestingT, err error, target interface{}, msgAndArgs ...interface{
 		return true
 	}
 
-	expectedText := reflect.ValueOf(target).Elem().Type().String()
+	expectedType := reflect.TypeOf(target).Elem().String()
 	if err == nil {
 		return Fail(t, fmt.Sprintf("An error is expected but got nil.\n"+
-			"expected: %s", expectedText), msgAndArgs...)
+			"expected: %s", expectedType), msgAndArgs...)
 	}
 
 	chain := buildErrorChainString(err, true)
 
 	return Fail(t, fmt.Sprintf("Should be in error chain:\n"+
 		"expected: %s\n"+
-		"in chain: %s", expectedText, chain,
+		"in chain: %s", expectedType, chain,
 	), msgAndArgs...)
 }
 
@@ -2245,7 +2245,7 @@ func NotErrorAs(t TestingT, err error, target interface{}, msgAndArgs ...interfa
 
 	return Fail(t, fmt.Sprintf("Target error should not be in err chain:\n"+
 		"found: %s\n"+
-		"in chain: %s", reflect.ValueOf(target).Elem().Type(), chain,
+		"in chain: %s", reflect.TypeOf(target).Elem().String(), chain,
 	), msgAndArgs...)
 }