From e4a571f345fa5e490247a40766992a773df26c64 Mon Sep 17 00:00:00 2001
From: Nikhil Sinha <nikhil@replicate.com>
Date: Mon, 28 Apr 2025 17:17:00 -0700
Subject: [PATCH 1/2] Add util function to copy fields between structs

---
 util/util.go      |  23 +++++++
 util/util_test.go | 160 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 183 insertions(+)
 create mode 100644 util/util.go
 create mode 100644 util/util_test.go

diff --git a/util/util.go b/util/util.go
new file mode 100644
index 0000000..1e5c400
--- /dev/null
+++ b/util/util.go
@@ -0,0 +1,23 @@
+package util
+
+import "reflect"
+
+// CopyFields copies any fields with the same name and type from one struct to another
+func CopyFields[A any, B any](a *A, b *B) {
+	val := reflect.Indirect(reflect.ValueOf(a))
+	val2 := reflect.Indirect(reflect.ValueOf(b))
+	for i := 0; i < val.Type().NumField(); i++ {
+		name := val.Type().Field(i).Name
+		field := val2.FieldByName(name)
+		if !field.IsValid() {
+			continue
+		}
+		if val.Type().Field(i).Type != field.Type() {
+			continue
+		}
+		if !val.Type().Field(i).IsExported() {
+			continue
+		}
+		field.Set(reflect.Indirect(reflect.ValueOf(a)).FieldByName(name))
+	}
+}
diff --git a/util/util_test.go b/util/util_test.go
new file mode 100644
index 0000000..42ca0dc
--- /dev/null
+++ b/util/util_test.go
@@ -0,0 +1,160 @@
+package util
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCopyFields_Normal(t *testing.T) {
+	type a struct {
+		Thing        int
+		AnotherThing string
+		OneMoreThing bool
+	}
+
+	type b struct {
+		Thing        int
+		AnotherThing string
+	}
+
+	thing1 := &a{
+		Thing:        123,
+		AnotherThing: "abc",
+		OneMoreThing: false,
+	}
+
+	thing2 := &b{}
+
+	CopyFields(thing1, thing2)
+	assert.Equal(t, thing2.Thing, 123)
+	assert.Equal(t, thing2.AnotherThing, "abc")
+}
+
+func TestCopyFields_Unexported(t *testing.T) {
+	type a struct {
+		thing        int
+		anotherThing string
+		oneMoreThing bool
+	}
+
+	type b struct {
+		thing        int
+		anotherThing string
+	}
+
+	thing1 := &a{
+		thing:        123,
+		anotherThing: "abc",
+		oneMoreThing: false,
+	}
+
+	thing2 := &b{}
+
+	CopyFields(thing1, thing2)
+	assert.Equal(t, thing2.thing, 0)
+	assert.Equal(t, thing2.anotherThing, "")
+}
+
+func TestCopyFields_DifferentType(t *testing.T) {
+	type a struct {
+		Thing        int
+		AnotherThing string
+		OneMoreThing bool
+	}
+
+	type b struct {
+		Thing        int
+		AnotherThing string
+		OneMoreThing string
+	}
+
+	thing1 := &a{
+		Thing:        123,
+		AnotherThing: "abc",
+		OneMoreThing: false,
+	}
+
+	thing2 := &b{}
+
+	CopyFields(thing1, thing2)
+	assert.Equal(t, thing2.Thing, 123)
+	assert.Equal(t, thing2.AnotherThing, "abc")
+	assert.Equal(t, thing2.OneMoreThing, "")
+}
+
+func TestCopyFields_UnexportedReceiver(t *testing.T) {
+	type a struct {
+		Thing        int
+		AnotherThing string
+		OneMoreThing bool
+	}
+
+	type b struct {
+		thing        int
+		anotherThing string
+	}
+
+	thing1 := &a{
+		Thing:        123,
+		AnotherThing: "abc",
+		OneMoreThing: false,
+	}
+
+	thing2 := &b{}
+
+	CopyFields(thing1, thing2)
+	assert.Equal(t, thing2.thing, 0)
+	assert.Equal(t, thing2.anotherThing, "")
+}
+
+func TestCopyFields_RefField(t *testing.T) {
+	type a struct {
+		Thing        map[string]string
+		AnotherThing string
+	}
+
+	type b struct {
+		Thing map[string]string
+	}
+
+	thing1 := &a{
+		Thing: map[string]string{
+			"a": "b",
+			"c": "d",
+		},
+	}
+
+	thing2 := &b{}
+
+	CopyFields(thing1, thing2)
+	assert.Equal(t, thing2.Thing, map[string]string{
+		"a": "b",
+		"c": "d",
+	})
+}
+
+func TestCopyFields_Func(t *testing.T) {
+	type a struct {
+		Thing        func(int) string
+		AnotherThing int
+	}
+
+	type b struct {
+		Thing        func(int) string
+		AnotherThing string
+	}
+
+	thing1 := &a{
+		Thing: func(i int) string {
+			return fmt.Sprintf("hello %d", i)
+		},
+	}
+
+	thing2 := &b{}
+
+	CopyFields(thing1, thing2)
+	assert.Equal(t, thing2.Thing(123), "hello 123")
+	assert.Equal(t, thing2.AnotherThing, "")
+}

From 3fd2d90d431db95146c52759d1552d320c5b6151 Mon Sep 17 00:00:00 2001
From: Nikhil Sinha <nikhil@replicate.com>
Date: Mon, 28 Apr 2025 17:27:45 -0700
Subject: [PATCH 2/2] Rename files

---
 util/{util.go => copy.go}           | 0
 util/{util_test.go => copy_test.go} | 0
 2 files changed, 0 insertions(+), 0 deletions(-)
 rename util/{util.go => copy.go} (100%)
 rename util/{util_test.go => copy_test.go} (100%)

diff --git a/util/util.go b/util/copy.go
similarity index 100%
rename from util/util.go
rename to util/copy.go
diff --git a/util/util_test.go b/util/copy_test.go
similarity index 100%
rename from util/util_test.go
rename to util/copy_test.go