embed original structs in debug structs

sync/cond.go

@@ -1,5 +1,11 @@
 package sync
 
-// Cond is only defined for compatibility reasons
+import (
+	_sync "sync"
+)
+
+// Cond implements a condition variable, a rendezvous point for goroutines
+// waiting for or announcing the occurrence of an event.
 type Cond struct {
+	_sync.Cond
 }

sync/locker.go

@@ -1,7 +1,10 @@
 package sync
 
-// Locker is only defined for compatibility reasons
+import (
+	_sync "sync"
+)
+
+// A Locker represents an object that can be locked and unlocked.
 type Locker interface {
-	Lock()
-	Unlock()
+	_sync.Locker
 }

sync/map.go

@@ -1,5 +1,12 @@
 package sync
 
-// Map is only defined for compatibility reasons
+import (
+	_sync "sync"
+)
+
+// Map is like a Go map[interface{}]interface{} but is safe for concurrent use
+// by multiple goroutines without additional locking or coordination. Loads,
+// stores, and deletes run in amortized constant time.
 type Map struct {
+	_sync.Map
 }

sync/once.go

@@ -1,5 +1,11 @@
 package sync
 
-// Once is only defined for compatibility reasons
+import (
+	_sync "sync"
+)
+
+// Once is an object that will perform exactly one action.
+// Once is an object that will perform exactly one action.
 type Once struct {
+	_sync.Once
 }

sync/pool.go

@@ -1,5 +1,11 @@
 package sync
 
-// Pool is only defined for compatibility reasons
+import (
+	_sync "sync"
+)
+
+// A Pool is a set of temporary objects that may be individually saved
+// and retrieved.
 type Pool struct {
+	_sync.Pool
 }