deepcopy: Attach location information to more errors

Author: LukeShu

pkg/deepcopy/traverse.go

@@ -490,7 +490,7 @@ func (c *copyMethodMaker) genStructDeepCopy(_ *namingInfo, structType *types.Str
 		case *types.Basic:
 			switch underlyingField.Kind() {
 			case types.Invalid, types.UnsafePointer:
-				c.pkg.AddError(fmt.Errorf("invalid field type: %s", underlyingField))
+				c.pkg.AddError(loader.ErrFromNode(fmt.Errorf("invalid field type: %s", underlyingField), field))
 				return
 			default:
 				// nothing to do, initial assignment copied this
@@ -502,7 +502,7 @@ func (c *copyMethodMaker) genStructDeepCopy(_ *namingInfo, structType *types.Str
 				c.Linef("in.%[1]s.DeepCopyInto(&out.%[1]s)", field.Name())
 			}
 		default:
-			c.pkg.AddError(fmt.Errorf("invalid field type: %s", underlyingField))
+			c.pkg.AddError(loader.ErrFromNode(fmt.Errorf("invalid field type: %s", underlyingField), field))
 			return
 		}
 	}

pkg/loader/errors.go

@@ -18,7 +18,6 @@ package loader
 
 import (
 	"fmt"
-	"go/ast"
 	"go/token"
 )
 
@@ -29,10 +28,15 @@ type PositionedError struct {
 	error
 }
 
+// Node is the intersection of go/ast.Node and go/types.Var.
+type Node interface {
+	Pos() token.Pos // position of first character belonging to the node
+}
+
 // ErrFromNode returns the given error, with additional information
 // attaching it to the given AST node.  It will automatically map
 // over error lists.
-func ErrFromNode(err error, node ast.Node) error {
+func ErrFromNode(err error, node Node) error {
 	if asList, isList := err.(ErrList); isList {
 		resList := make(ErrList, len(asList))
 		for i, baseErr := range asList {