fix: allow %T verb to not be wrapped

- closes #81

Author: ehsundar

errorlint/lint.go

@@ -82,7 +82,7 @@ func LintFmtErrorfCalls(fset *token.FileSet, info types.Info, multipleWraps bool
 					argIndex++
 				}
 
-				if verb.format == "w" {
+				if verb.format == "w" || verb.format == "T" {
 					continue
 				}
 				if argIndex-1 >= len(args) {

errorlint/testdata/src/fmterrorf/fmterrorf.go

@@ -15,6 +15,11 @@ func NonWrappingVerb() error {
 	return fmt.Errorf("error: %v", err) // want "non-wrapping format verb for fmt.Errorf. Use `%w` to format errors"
 }
 
+func NonWrappingTVerb() error {
+	err := errors.New("oops")
+	return fmt.Errorf("error: %T", err)
+}
+
 func DoubleNonWrappingVerb() error {
 	err := errors.New("oops")
 	return fmt.Errorf("%v %v", err, err) // want "non-wrapping format verb for fmt.Errorf. Use `%w` to format errors"
@@ -27,6 +32,13 @@ func ErrorOneWrap() error {
 	return fmt.Errorf("%v, %w, %v", err1, err2, err3) // want "non-wrapping format verb for fmt.Errorf. Use `%w` to format errors"
 }
 
+func ValidNonWrappingTVerb() error {
+	err1 := errors.New("oops1")
+	err2 := errors.New("oops2")
+	err3 := errors.New("oops3")
+	return fmt.Errorf("%w, %T, %w", err1, err2, err3)
+}
+
 func ErrorMultipleWraps() error {
 	err1 := errors.New("oops1")
 	err2 := errors.New("oops2")

errorlint/testdata/src/fmterrorf/fmterrorf.go.golden

@@ -15,6 +15,11 @@ func NonWrappingVerb() error {
 	return fmt.Errorf("error: %w", err) // want "non-wrapping format verb for fmt.Errorf. Use `%w` to format errors"
 }
 
+func NonWrappingTVerb() error {
+	err := errors.New("oops")
+	return fmt.Errorf("error: %T", err)
+}
+
 func DoubleNonWrappingVerb() error {
 	err := errors.New("oops")
 	return fmt.Errorf("%w %w", err, err) // want "non-wrapping format verb for fmt.Errorf. Use `%w` to format errors"
@@ -27,6 +32,13 @@ func ErrorOneWrap() error {
 	return fmt.Errorf("%w, %w, %w", err1, err2, err3) // want "non-wrapping format verb for fmt.Errorf. Use `%w` to format errors"
 }
 
+func ValidNonWrappingTVerb() error {
+	err1 := errors.New("oops1")
+	err2 := errors.New("oops2")
+	err3 := errors.New("oops3")
+	return fmt.Errorf("%w, %T, %w", err1, err2, err3)
+}
+
 func ErrorMultipleWraps() error {
 	err1 := errors.New("oops1")
 	err2 := errors.New("oops2")