From 9a59bdb2396397ead57d1e7112b3c83dc4df7831 Mon Sep 17 00:00:00 2001
From: Jared Wasinger <j-wasinger@hotmail.com>
Date: Thu, 12 Dec 2024 13:28:03 +0700
Subject: [PATCH] generation of custom error unpacking builds (not tested yet)

---
 accounts/abi/bind/bind.go                      |  5 +++++
 accounts/abi/bind/source2.go.tpl               | 18 ++++++++++++++++++
 .../bind/v2/internal/solc_errors/bindings.go   |  9 +++++++++
 3 files changed, 32 insertions(+)

diff --git a/accounts/abi/bind/bind.go b/accounts/abi/bind/bind.go
index ea4ed55540..c25aff450f 100644
--- a/accounts/abi/bind/bind.go
+++ b/accounts/abi/bind/bind.go
@@ -70,6 +70,10 @@ func isKeyWord(arg string) bool {
 	return true
 }
 
+func add(val1, val2 int) int {
+	return val1 + val1
+}
+
 // Bind generates a Go wrapper around a contract ABI. This wrapper isn't meant
 // to be used as is in client code, but rather as an intermediate struct which
 // enforces compile time type safety and naming convention as opposed to having to
@@ -146,6 +150,7 @@ func BindV2(types []string, abis []string, bytecodes []string, fsigs []map[strin
 		"bindtopictype": bindTopicType,
 		"capitalise":    capitalise,
 		"decapitalise":  decapitalise,
+		"add":           add,
 	}
 	tmpl := template.Must(template.New("").Funcs(funcs).Parse(tmplSourceV2))
 	if err := tmpl.Execute(buffer, data); err != nil {
diff --git a/accounts/abi/bind/source2.go.tpl b/accounts/abi/bind/source2.go.tpl
index 990988bbf1..62d17d2c17 100644
--- a/accounts/abi/bind/source2.go.tpl
+++ b/accounts/abi/bind/source2.go.tpl
@@ -151,6 +151,24 @@ var (
 		}
 	{{end}}
 
+    {{ if .Errors }}
+    func (_{{$contract.Type}} *{{$contract.Type}}) UnpackError(raw []byte) any {
+        {{$i := 0}}
+        {{range $k, $v := .Errors}}
+            {{ if eq $i 0 }}
+                if val, err := _{{$contract.Type}}.Unpack{{.Normalized.Name}}Error(raw); err != nil {
+                    return val
+            {{ else }}
+                } else if val, err := _{{$contract.Type}}.Unpack{{.Normalized.Name}}Error(raw); err != nil {
+                    return val
+            {{ end -}}
+            {{$i = add $i 1}}
+        {{end -}}
+        }
+        return nil
+    }
+    {{ end -}}
+
     {{range .Errors}}
 		// {{$contract.Type}}{{.Normalized.Name}} represents a {{.Normalized.Name}} error raised by the {{$contract.Type}} contract.
 		type {{$contract.Type}}{{.Normalized.Name}} struct { {{range .Normalized.Inputs}}
diff --git a/accounts/abi/bind/v2/internal/solc_errors/bindings.go b/accounts/abi/bind/v2/internal/solc_errors/bindings.go
index 1af79d97b3..8067dd2e96 100644
--- a/accounts/abi/bind/v2/internal/solc_errors/bindings.go
+++ b/accounts/abi/bind/v2/internal/solc_errors/bindings.go
@@ -58,6 +58,15 @@ func (_C *C) PackFoo() ([]byte, error) {
 	return _C.abi.Pack("Foo")
 }
 
+func (_C *C) UnpackError(raw []byte) any {
+
+	if val, err := _C.UnpackBadThingError(raw); err != nil {
+		return val
+
+	}
+	return nil
+}
+
 // CBadThing represents a BadThing error raised by the C contract.
 type CBadThing struct {
 	Arg1 *big.Int