document: add Clear method to Run

document/run.go

@@ -72,6 +72,11 @@ func (r Run) newIC() *wml.EG_RunInnerContent {
 	return ic
 }
 
+// Clear removes all of the content from within a run.
+func (r Run) Clear() {
+	r.x.EG_RunInnerContent = nil
+}
+
 // AddTab adds tab to a run and can be used with the the Paragraph's tab stops.
 func (r Run) AddTab() {
 	ic := r.newIC()

document/run_test.go

@@ -0,0 +1,37 @@
+// Copyright 2017 Baliance. All rights reserved.
+//
+// Use of this source code is governed by the terms of the Affero GNU General
+// Public License version 3.0 as published by the Free Software Foundation and
+// appearing in the file LICENSE included in the packaging of this file. A
+// commercial license can be purchased by contacting [email protected].
+
+package document_test
+
+import (
+	"testing"
+
+	"baliance.com/gooxml/document"
+)
+
+func TestRunClear(t *testing.T) {
+	doc := document.New()
+	para := doc.AddParagraph()
+	run := para.AddRun()
+	if len(run.X().EG_RunInnerContent) != 0 {
+		t.Errorf("expected inner content of length zero, had %d", len(run.X().EG_RunInnerContent))
+	}
+	for i := 0; i < 5; i++ {
+		if i%2 == 0 {
+			run.AddText("test")
+		} else {
+			run.AddTab()
+		}
+		if len(run.X().EG_RunInnerContent) != i+1 {
+			t.Errorf("expected inner content of length %d, had %d", i+1, len(run.X().EG_RunInnerContent))
+		}
+	}
+	run.Clear()
+	if len(run.X().EG_RunInnerContent) != 0 {
+		t.Errorf("expected inner content of length zero, had %d", len(run.X().EG_RunInnerContent))
+	}
+}