From f39c3724a124648bed4748608f75bb91fcc3555b Mon Sep 17 00:00:00 2001
From: Cory Redmond <code@cory.red>
Date: Tue, 23 Mar 2021 23:22:22 +0000
Subject: [PATCH] Allow recursion using ...

---
 sqlstruct.go      | 18 ++++++++++++++----
 sqlstruct_test.go | 15 +++++++++++++++
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/sqlstruct.go b/sqlstruct.go
index bd9756b..402d10d 100644
--- a/sqlstruct.go
+++ b/sqlstruct.go
@@ -13,10 +13,20 @@ with "encoding/json" package.
 
 For example:
 
+	type T1 struct {
+		F4 string `sql:"field4"`
+    }
+
+	type T2 struct {
+		F5 string `sql:"field5"`
+	}
+
     type T struct {
-        F1 string
-        F2 string `sql:"field2"`
-        F3 string `sql:"-"`
+        F1      string
+        F2      string `sql:"field2"`
+        F3      string `sql:"-"`
+		fieldT1 T1     `sql:"..."`
+		T2
     }
 
     rows, err := db.Query(fmt.Sprintf("SELECT %s FROM tablename", sqlstruct.Columns(T{})))
@@ -146,7 +156,7 @@ func getFieldInfo(typ reflect.Type) fieldInfo {
 		}
 
 		// Handle embedded structs
-		if f.Anonymous && f.Type.Kind() == reflect.Struct {
+		if (f.Anonymous || tag == "...") && f.Type.Kind() == reflect.Struct {
 			for k, v := range getFieldInfo(f.Type) {
 				finfo[k] = append([]int{i}, v...)
 			}
diff --git a/sqlstruct_test.go b/sqlstruct_test.go
index be6e940..61b5b8e 100644
--- a/sqlstruct_test.go
+++ b/sqlstruct_test.go
@@ -25,6 +25,11 @@ type testType2 struct {
 	FieldSec string `sql:"field_sec"`
 }
 
+type testType3 struct {
+	FieldA string `sql:"field_a"`
+	EmbeddedType EmbeddedType `sql:"..."`
+}
+
 // testRows is a mock version of sql.Rows which can only scan strings
 type testRows struct {
 	columns []string
@@ -67,6 +72,16 @@ func TestColumns(t *testing.T) {
 	}
 }
 
+func TestColumnDeep(t *testing.T) {
+	var v testType3
+	e := "field_a, field_e"
+	c := Columns(v)
+
+	if c != e {
+		t.Errorf("expected %q got %q", e, c)
+	}
+}
+
 func TestColumnsAliased(t *testing.T) {
 	var t1 testType
 	var t2 testType2