From c3c09204ab54b1739160dbd0cb17d71f27666b4a Mon Sep 17 00:00:00 2001
From: Onsi Fakhouri <onsijoe@gmail.com>
Date: Sun, 7 Mar 2021 14:31:11 -0700
Subject: [PATCH] Add Clear() method to gbytes.Buffer

---
 gbytes/buffer.go      | 16 ++++++++++++++++
 gbytes/buffer_test.go | 20 ++++++++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/gbytes/buffer.go b/gbytes/buffer.go
index 336086f4a..809f3c543 100644
--- a/gbytes/buffer.go
+++ b/gbytes/buffer.go
@@ -108,6 +108,22 @@ func (b *Buffer) Read(d []byte) (int, error) {
 	return n, nil
 }
 
+/*
+Clear clears out the buffer's contents
+*/
+func (b *Buffer) Clear() error {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	if b.closed {
+		return errors.New("attempt to clear closed buffer")
+	}
+
+	b.contents = []byte{}
+	b.readCursor = 0
+	return nil
+}
+
 /*
 Close signifies that the buffer will no longer be written to
 */
diff --git a/gbytes/buffer_test.go b/gbytes/buffer_test.go
index 9d4e8279d..4319d8d32 100644
--- a/gbytes/buffer_test.go
+++ b/gbytes/buffer_test.go
@@ -181,6 +181,26 @@ var _ = Describe("Buffer", func() {
 		})
 	})
 
+	Describe("clearing the buffer", func() {
+		It("should clear out the contents of the buffer", func() {
+			buffer.Write([]byte("abc"))
+			Expect(buffer).To(Say("ab"))
+			Expect(buffer.Clear()).To(Succeed())
+			Expect(buffer).NotTo(Say("c"))
+			Expect(buffer.Contents()).To(BeEmpty())
+			buffer.Write([]byte("123"))
+			Expect(buffer).To(Say("123"))
+			Expect(buffer.Contents()).To(Equal([]byte("123")))
+		})
+
+		It("should error when the buffer is closed", func() {
+			buffer.Write([]byte("abc"))
+			buffer.Close()
+			err := buffer.Clear()
+			Expect(err).To(HaveOccurred())
+		})
+	})
+
 	Describe("closing the buffer", func() {
 		It("should error when further write attempts are made", func() {
 			_, err := buffer.Write([]byte("abc"))