Add Buffer::Iterator functions to move forward/backward on/up to characters in a line

src/core/Buffer-Iterator.cc

@@ -202,6 +202,80 @@ void Buffer::Iterator::warp_to_offset(size_t offset)
     }
 }
 
+bool Buffer::Iterator::go_forward_in_line_up_to_char(uint32_t c)
+{
+    size_t last_offset = m_offset;
+    Buffer::Iterator it = *this;
+    while (it.go_right_in_line(false))
+    {
+        if (*it == c)
+        {
+            if (last_offset != m_offset)
+            {
+                m_offset = last_offset;
+                return true;
+            }
+            else
+            {
+                return false;
+            }
+        }
+        last_offset = it.m_offset;
+    }
+    return false;
+}
+
+bool Buffer::Iterator::go_forward_in_line_on_to_char(uint32_t c)
+{
+    Buffer::Iterator it = *this;
+    while (it.go_right_in_line(false))
+    {
+        if (*it == c)
+        {
+            m_offset = it.m_offset;
+            return true;
+        }
+    }
+    return false;
+}
+
+bool Buffer::Iterator::go_backward_in_line_up_to_char(uint32_t c)
+{
+    size_t last_offset = m_offset;
+    Buffer::Iterator it = *this;
+    while (it.go_left_in_line())
+    {
+        if (*it == c)
+        {
+            if (last_offset != m_offset)
+            {
+                m_offset = last_offset;
+                return true;
+            }
+            else
+            {
+                return false;
+            }
+        }
+        last_offset = it.m_offset;
+    }
+    return false;
+}
+
+bool Buffer::Iterator::go_backward_in_line_on_to_char(uint32_t c)
+{
+    Buffer::Iterator it = *this;
+    while (it.go_left_in_line())
+    {
+        if (*it == c)
+        {
+            m_offset = it.m_offset;
+            return true;
+        }
+    }
+    return false;
+}
+
 Buffer::Iterator Buffer::Iterator::prev()
 {
     Iterator i = *this;

src/core/Buffer.h

@@ -49,6 +49,10 @@ public:
         bool go_right_in_line(bool allow_eol);
         bool go_previous_line();
         bool go_next_line();
+        bool go_forward_in_line_up_to_char(uint32_t c);
+        bool go_forward_in_line_on_to_char(uint32_t c);
+        bool go_backward_in_line_up_to_char(uint32_t c);
+        bool go_backward_in_line_on_to_char(uint32_t c);
         Iterator prev();
         Iterator next();
         void warp(ssize_t offset_offset, ssize_t line_offset)