From 6ba70ed046214de9b570a6257ff1c14f8b97647f Mon Sep 17 00:00:00 2001
From: Sasha Koshka <sashakoshka@tebibyte.media>
Date: Sat, 5 Jul 2025 18:47:08 -0400
Subject: [PATCH] internal/testutil: Create function to closely examine any
 data

---
 internal/testutil/testutil.go | 67 +++++++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/internal/testutil/testutil.go b/internal/testutil/testutil.go
index 401c9a2..4295b92 100644
--- a/internal/testutil/testutil.go
+++ b/internal/testutil/testutil.go
@@ -3,6 +3,7 @@ package testutil
 import "fmt"
 import "slices"
 import "strings"
+import "reflect"
 
 // Snake lets you compare blocks of data where the ordering of certain parts may
 // be swapped every which way. It is designed for comparing the encoding of
@@ -92,3 +93,69 @@ func HexBytes(data []byte) string {
 	}
 	return out.String()
 }
+
+// Describe returns a string representing the type and data of the given value.
+func Describe(value any) string {
+	desc := describer { }
+	desc.describe(reflect.ValueOf(value))
+	return desc.String()
+}
+
+type describer struct {
+	strings.Builder
+	indent int
+}
+
+func (this *describer) describe(value reflect.Value) {
+	value = reflect.ValueOf(value.Interface())
+	switch value.Kind() {
+	case reflect.Array, reflect.Slice:
+		this.printf("[\n")
+		this.indent += 1
+		for index := 0; index < value.Len(); index ++ {
+			this.iprintf("")
+			this.describe(value.Index(index))
+			this.iprintf("\n")
+		}
+		this.indent -= 1
+		this.iprintf("]")
+	case reflect.Struct:
+		this.printf("struct {\n")
+		this.indent += 1
+		typ := value.Type()
+		for index := range typ.NumField() {
+			indexBuffer := [1]int { index }
+			this.iprintf("%s: ", typ.Field(index).Name)
+			this.describe(value.FieldByIndex(indexBuffer[:]))
+			this.iprintf("\n")
+		}
+		this.indent -= 1
+		this.iprintf("}\n")
+	case reflect.Map:
+		this.printf("map {\n")
+		this.indent += 1
+		iter := value.MapRange()
+		for iter.Next() {
+			this.iprintf("")
+			this.describe(iter.Key())
+			this.printf(": ")
+			this.describe(iter.Value())
+			this.iprintf("\n")
+		}
+		this.indent -= 1
+		this.iprintf("}\n")
+	case reflect.Pointer:
+		this.printf("& ")
+		this.describe(value.Elem())
+	default:
+		this.printf("<%v %v>", value.Type(), value.Interface())
+	}
+}
+
+func (this *describer) printf(format string, v ...any) {
+	fmt.Fprintf(this, format, v...)
+}
+
+func (this *describer) iprintf(format string, v ...any) {
+	fmt.Fprintf(this, strings.Repeat("\t", this.indent) + format, v...)
+}