Merge pull request #3 from jsteenb2/feat/stack_frames_formatter

feat: add formatter for StackFrames

errors_test.go

@@ -243,17 +243,6 @@ func isT[T any](t *testing.T, v any) T {
 	return out
 }
 
-func isErr(t *testing.T, err error) bool {
-	t.Helper()
-
-	matches := err != nil
-	if !matches {
-		t.Fatalf("expected error:\n\t\tgot:\t%v", err)
-	}
-
-	return matches
-}
-
 func must(t *testing.T, outcome bool) {
 	t.Helper()
 

frame.go

@@ -62,6 +62,35 @@ func (f Frame) Format(s fmt.State, verb rune) {
 //  2. add Formatter to be able to turn off the way it prints
 type StackFrames []Frame
 
+// String formats Frame to string.
+func (f StackFrames) String() string {
+	var sb strings.Builder
+	sb.WriteString("[ ")
+
+	for i, frame := range f {
+		sb.WriteString(frame.String())
+		if i < len(f)-1 {
+			sb.WriteString(", ")
+		}
+	}
+	if sb.Len() > 2 {
+		sb.WriteString(" ")
+	}
+	sb.WriteString("]")
+	return sb.String()
+}
+
+// Format formats the frame according to the fmt.Formatter interface.
+// See Frame.Format for the formatting rules.
+func (f StackFrames) Format(s fmt.State, verb rune) {
+	for i, frame := range f {
+		frame.Format(s, verb)
+		if i < len(f)-1 {
+			io.WriteString(s, "\n\n")
+		}
+	}
+}
+
 func getFrame(skip FrameSkips) (Frame, bool) {
 	if skip == NoFrame {
 		return Frame{}, false

frame_test.go

@@ -7,32 +7,90 @@ import (
 	"github.com/jsteenb2/errors"
 )
 
-func TestStackTrace(t *testing.T) {
+func TestStackTrace_SimpleError(t *testing.T) {
 	err := errors.New("some error")
-	isErr(t, err)
 
 	frames := errors.StackTrace(err)
 	must(t, eqLen(t, 1, frames))
 
-	sVal := fmt.Sprintf("%s", frames[0])
+	eq(t, "[ github.com/jsteenb2/errors/frame_test.go:11[TestStackTrace_SimpleError] ]", frames.String())
+
+	sVal := fmt.Sprintf("%s", frames)
+	eq(t, "frame_test.go", sVal)
+
+	sVal = fmt.Sprintf("%s", frames[0])
 	eq(t, "frame_test.go", sVal)
 
-	wantSPlusVal := `github.com/jsteenb2/errors_test.TestStackTrace
+	wantSPlusVal := `github.com/jsteenb2/errors_test.TestStackTrace_SimpleError
 	github.com/jsteenb2/errors/frame_test.go`
 
-	sPlusVal := fmt.Sprintf("%+s", frames[0])
+	sPlusVal := fmt.Sprintf("%+s", frames)
+	eq(t, wantSPlusVal, sPlusVal)
+
+	sPlusVal = fmt.Sprintf("%+s", frames[0])
 	eq(t, wantSPlusVal, sPlusVal)
 
-	dVal := fmt.Sprintf("%d", frames[0])
 	wantLine := "11"
+	dVal := fmt.Sprintf("%d", frames)
+	eq(t, wantLine, dVal)
+	dVal = fmt.Sprintf("%d", frames[0])
 	eq(t, wantLine, dVal)
 
-	vVal := fmt.Sprintf("%v", frames[0])
-	wantFile := "frame_test.go:11"
+	wantFile := "frame_test.go:" + wantLine
+	vVal := fmt.Sprintf("%v", frames)
+	eq(t, wantFile, vVal)
+	vVal = fmt.Sprintf("%v", frames[0])
 	eq(t, wantFile, vVal)
 
-	wantVPlusVal := `github.com/jsteenb2/errors_test.TestStackTrace
+	wantVPlusVal := `github.com/jsteenb2/errors_test.TestStackTrace_SimpleError
 	github.com/jsteenb2/errors/` + wantFile
-	vPlusVal := fmt.Sprintf("%+v", frames[0])
+	vPlusVal := fmt.Sprintf("%+v", frames)
+	eq(t, wantVPlusVal, vPlusVal)
+	vPlusVal = fmt.Sprintf("%+v", frames[0])
 	eq(t, wantVPlusVal, vPlusVal)
 }
+
+func TestStackTrace_WrappedError(t *testing.T) {
+	err := errors.Wrap(
+		errors.New("some error"),
+	)
+
+	frames := errors.StackTrace(err)
+	must(t, eqLen(t, 2, frames))
+
+	wantStr := "[ github.com/jsteenb2/errors/frame_test.go:54[TestStackTrace_WrappedError], github.com/jsteenb2/errors/frame_test.go:55[TestStackTrace_WrappedError] ]"
+	eq(t, wantStr, frames.String())
+
+	eq(t, "frame_test.go\n\nframe_test.go", fmt.Sprintf("%s", frames))
+	eq(t, "frame_test.go", fmt.Sprintf("%s", frames[0]))
+	eq(t, "frame_test.go", fmt.Sprintf("%s", frames[1]))
+
+	wantSPlusVal := `github.com/jsteenb2/errors_test.TestStackTrace_WrappedError
+	github.com/jsteenb2/errors/frame_test.go
+
+github.com/jsteenb2/errors_test.TestStackTrace_WrappedError
+	github.com/jsteenb2/errors/frame_test.go`
+	eq(t, wantSPlusVal, fmt.Sprintf("%+s", frames))
+
+	wantSPlusVal = `github.com/jsteenb2/errors_test.TestStackTrace_WrappedError
+	github.com/jsteenb2/errors/frame_test.go`
+	eq(t, wantSPlusVal, fmt.Sprintf("%+s", frames[0]))
+	eq(t, wantSPlusVal, fmt.Sprintf("%+s", frames[1]))
+
+	eq(t, "54\n\n55", fmt.Sprintf("%d", frames))
+	eq(t, "54", fmt.Sprintf("%d", frames[0]))
+	eq(t, "55", fmt.Sprintf("%d", frames[1]))
+
+	wantFile := `frame_test.go:54
+
+frame_test.go:55`
+	eq(t, wantFile, fmt.Sprintf("%v", frames))
+	eq(t, "frame_test.go:54", fmt.Sprintf("%v", frames[0]))
+	eq(t, "frame_test.go:55", fmt.Sprintf("%v", frames[1]))
+
+	wantVPlusFrame := `github.com/jsteenb2/errors_test.TestStackTrace_WrappedError
+	github.com/jsteenb2/errors/frame_test.go`
+	eq(t, wantVPlusFrame+":54\n\n"+wantVPlusFrame+":55", fmt.Sprintf("%+v", frames))
+	eq(t, wantVPlusFrame+":54", fmt.Sprintf("%+v", frames[0]))
+	eq(t, wantVPlusFrame+":55", fmt.Sprintf("%+v", frames[1]))
+}