[gtksourceview] Add a buffer_join_lines method

[Paolo Borelli <pborelli src gnome org>]

commit baa0febd8ae5a982b7929f7cc418d5a89268566b
Author: Paolo Borelli <pborelli gnome org>
Date:   Sun Jan 18 14:36:41 2015 +0100

    Add a buffer_join_lines method

 docs/reference/gtksourceview-3.0-sections.txt |    1 +
 gtksourceview/gtksourcebuffer.c               |   96 +++++++++++++++++++++++++
 gtksourceview/gtksourcebuffer.h               |    4 +
 tests/test-buffer.c                           |   46 ++++++++++++
 4 files changed, 147 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/gtksourceview-3.0-sections.txt b/docs/reference/gtksourceview-3.0-sections.txt
index de20088..8b3e2bd 100644
--- a/docs/reference/gtksourceview-3.0-sections.txt
+++ b/docs/reference/gtksourceview-3.0-sections.txt
@@ -43,6 +43,7 @@ gtk_source_buffer_get_source_marks_at_iter
 gtk_source_buffer_remove_source_marks
 <SUBSECTION Other>
 gtk_source_buffer_change_case
+gtk_source_buffer_join_lines
 gtk_source_buffer_set_implicit_trailing_newline
 gtk_source_buffer_get_implicit_trailing_newline
 <SUBSECTION Standard>
diff --git a/gtksourceview/gtksourcebuffer.c b/gtksourceview/gtksourcebuffer.c
index 1714548..a44b873 100644
--- a/gtksourceview/gtksourcebuffer.c
+++ b/gtksourceview/gtksourcebuffer.c
@@ -2506,6 +2506,102 @@ gtk_source_buffer_change_case (GtkSourceBuffer         *buffer,
        g_free (new_text);
 }
 
+/* move to the end of the line excluding trailing spaces */
+static void
+move_to_line_text_end(GtkTextIter *iter)
+{
+       gint line;
+
+       line = gtk_text_iter_get_line (iter);
+
+       if (!gtk_text_iter_ends_line (iter))
+       {
+               gtk_text_iter_forward_to_line_end (iter);
+       }
+
+       while (gtk_text_iter_backward_char (iter) &&
+              (gtk_text_iter_get_line (iter) == line))
+       {
+               gunichar ch;
+
+               ch = gtk_text_iter_get_char (iter);
+               if (!g_unichar_isspace (ch))
+               {
+                       break;
+               }
+       }
+
+       gtk_text_iter_forward_char (iter);
+}
+
+/**
+ * gtk_source_buffer_join_lines:
+ * @buffer: a #GtkSourceBuffer.
+ * @start: a #GtkTextIter.
+ * @end: a #GtkTextIter.
+ *
+ * Joins the lines of text between the specified iterators.
+ *
+ * Since: 3.16
+ **/
+void
+gtk_source_buffer_join_lines (GtkSourceBuffer *buffer,
+                              GtkTextIter     *start,
+                              GtkTextIter     *end)
+{
+       GtkTextBuffer *text_buffer;
+       GtkTextMark *end_mark;
+
+       g_return_if_fail (GTK_SOURCE_IS_BUFFER (buffer));
+       g_return_if_fail (start != NULL);
+       g_return_if_fail (end != NULL);
+
+       if (gtk_text_iter_get_line (start) == gtk_text_iter_get_line (end))
+       {
+               return;
+       }
+
+       gtk_text_iter_order (start, end);
+
+       text_buffer = GTK_TEXT_BUFFER (buffer);
+       end_mark = gtk_text_buffer_create_mark (text_buffer, NULL, end, FALSE);
+
+       gtk_text_buffer_begin_user_action (text_buffer);
+
+       move_to_line_text_end (start);
+
+       while (gtk_text_iter_compare (start, end) < 0)
+       {
+               GtkTextIter iter;
+               gunichar ch;
+
+               iter = *start;
+
+               do
+               {
+                       ch = gtk_text_iter_get_char (&iter);
+                       if (!g_unichar_isspace (ch))
+                       {
+                               break;
+                       }
+               } while (gtk_text_iter_forward_char (&iter));
+
+               if (!gtk_text_iter_is_end (&iter))
+               {
+                       gtk_text_buffer_delete (text_buffer, start, &iter);
+                       gtk_text_buffer_insert (text_buffer, start, " ", 1);
+               }
+
+               move_to_line_text_end (start);
+
+               gtk_text_buffer_get_iter_at_mark (text_buffer, end, end_mark);
+       }
+
+       gtk_text_buffer_end_user_action (text_buffer);
+
+       gtk_text_buffer_delete_mark (text_buffer, end_mark);
+}
+
 /**
  * gtk_source_buffer_set_undo_manager:
  * @buffer: a #GtkSourceBuffer.
diff --git a/gtksourceview/gtksourcebuffer.h b/gtksourceview/gtksourcebuffer.h
index 449cca3..15876ca 100644
--- a/gtksourceview/gtksourcebuffer.h
+++ b/gtksourceview/gtksourcebuffer.h
@@ -198,6 +198,10 @@ void                        gtk_source_buffer_change_case                          
(GtkSourceBuffer        *buffer,
                                                                                 GtkTextIter            
*start,
                                                                                 GtkTextIter            *end);
 
+void                    gtk_source_buffer_join_lines                           (GtkSourceBuffer        
*buffer,
+                                                                                GtkTextIter            
*start,
+                                                                                GtkTextIter            *end);
+
 GtkSourceUndoManager   *gtk_source_buffer_get_undo_manager                     (GtkSourceBuffer        
*buffer);
 
 void                    gtk_source_buffer_set_undo_manager                     (GtkSourceBuffer        
*buffer,
diff --git a/tests/test-buffer.c b/tests/test-buffer.c
index cba7065..6392591 100644
--- a/tests/test-buffer.c
+++ b/tests/test-buffer.c
@@ -174,6 +174,51 @@ test_change_case (void)
        g_object_unref (buffer);
 }
 
+static void
+do_test_join_lines (GtkSourceBuffer *buffer,
+                   const gchar     *text,
+                   const gchar     *expected,
+                   gint             start_offset,
+                   gint             end_offset)
+{
+       GtkTextIter start;
+       GtkTextIter end;
+       gchar *changed;
+
+       gtk_text_buffer_set_text (GTK_TEXT_BUFFER (buffer), text, -1);
+
+       gtk_text_buffer_get_iter_at_offset (GTK_TEXT_BUFFER (buffer), &start, start_offset);
+       gtk_text_buffer_get_iter_at_offset (GTK_TEXT_BUFFER (buffer), &end, end_offset);
+
+       gtk_source_buffer_join_lines (buffer, &start, &end);
+
+       gtk_text_buffer_get_bounds (GTK_TEXT_BUFFER (buffer), &start, &end);
+       changed = gtk_text_buffer_get_text (GTK_TEXT_BUFFER (buffer), &start, &end, TRUE);
+
+       g_assert_cmpstr (changed, ==, expected);
+
+       g_free (changed);
+}
+
+static void
+test_join_lines (void)
+{
+       GtkSourceBuffer *buffer;
+
+       buffer = gtk_source_buffer_new (NULL);
+
+       do_test_join_lines (buffer, "some text", "some text", 0, -1);
+       do_test_join_lines (buffer, "some\ntext", "some text", 0, -1);
+       do_test_join_lines (buffer, "some\t  \n\t  text", "some text", 0, -1);
+       do_test_join_lines (buffer, "some\n\n\ntext", "some text", 0, -1);
+       do_test_join_lines (buffer, "some\ntext", "some\ntext", 0, 1);
+       do_test_join_lines (buffer, "some\ntext", "some\ntext", 6, -1);
+       do_test_join_lines (buffer, "some\ntext\nmore", "some text\nmore", 0, 6);
+       do_test_join_lines (buffer, "some\ntext\nmore", "some\ntext more", 6, -1);
+
+       g_object_unref (buffer);
+}
+
 int
 main (int argc, char** argv)
 {
@@ -184,6 +229,7 @@ main (int argc, char** argv)
        g_test_add_func ("/Buffer/bug-634510", test_get_buffer);
        g_test_add_func ("/Buffer/get-context-classes", test_get_context_classes);
        g_test_add_func ("/Buffer/change-case", test_change_case);
+       g_test_add_func ("/Buffer/join-lines", test_join_lines);
 
        return g_test_run();
 }