Add GapBuffer::erase()

src/core/GapBuffer.cc

@@ -33,6 +33,23 @@ void GapBuffer::insert(size_t position, const uint8_t * data, size_t length)
     m_size += length;
 }
 
+void GapBuffer::erase(size_t position, size_t length)
+{
+    if ((position < m_size) && ((position + length) <= m_size))
+    {
+        if ((position + length) == m_gap_position)
+        {
+            m_gap_position -= length;
+            m_size -= length;
+        }
+        else
+        {
+            move_gap(position);
+            m_size -= length;
+        }
+    }
+}
+
 std::string GapBuffer::get_string()
 {
     compact();

src/core/GapBuffer.h

@@ -46,6 +46,16 @@ public:
      */
     void insert(size_t position, const uint8_t * data, size_t length);
 
+    /**
+     * Erase data from the gap buffer.
+     *
+     * @param position
+     *   Position in the gap buffer to erase data from.
+     * @param length
+     *   Length of the data to erase.
+     */
+    void erase(size_t position, size_t length);
+
     /**
      * Get the contents of the gap buffer as a string.
      *

test/src/test_GapBuffer.cc

@@ -43,6 +43,35 @@ TEST(GapBufferTest, allows_inserting)
     EXPECT_EQ(8u, gp.size());
 }
 
+TEST(GapBufferTest, allows_deleting)
+{
+    GapBuffer gp;
+
+    gp.insert(0u, (const uint8_t *)"test_123", 8u);
+    EXPECT_EQ(8u, gp.size());
+    EXPECT_EQ("test_123", gp.get_string());
+
+    gp.erase(6u, 2u);
+    EXPECT_EQ(6u, gp.size());
+    EXPECT_EQ("test_1", gp.get_string());
+
+    gp.insert(4u, (const uint8_t *)"!@#$", 4u);
+    EXPECT_EQ(10u, gp.size());
+    EXPECT_EQ("test!@#$_1", gp.get_string());
+
+    gp.erase(4u, 4u);
+    EXPECT_EQ(6u, gp.size());
+    EXPECT_EQ("test_1", gp.get_string());
+
+    gp.insert(4u, (const uint8_t *)"^&", 2u);
+    EXPECT_EQ(8u, gp.size());
+    EXPECT_EQ("test^&_1", gp.get_string());
+
+    gp.erase(2u, 5u);
+    EXPECT_EQ(3u, gp.size());
+    EXPECT_EQ("te1", gp.get_string());
+}
+
 TEST(GapBufferTest, allocates_more_memory_and_copies_buffer_contents_when_needed)
 {
     GapBuffer gp;