[gtksourceview] changecase: better character conversions

[Sébastien Wilmet <swilmet src gnome org>]

commit fd545bd9e501df65e9c67c5d679d2b0c5fc5344f
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Thu Sep 25 17:20:22 2014 +0200

    changecase: better character conversions
    
    Moving by cursor positions gives better results, since between two
    cursor positions there may be several characters, like a letter+accent
    mark.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=416390

 gtksourceview/gtksourcebuffer.c |  187 +++++++++++++++++++++++++--------------
 tests/test-buffer.c             |   46 ++++++++--
 2 files changed, 160 insertions(+), 73 deletions(-)
---
diff --git a/gtksourceview/gtksourcebuffer.c b/gtksourceview/gtksourcebuffer.c
index d1d0385..61b0b54 100644
--- a/gtksourceview/gtksourcebuffer.c
+++ b/gtksourceview/gtksourcebuffer.c
@@ -2298,102 +2298,158 @@ gtk_source_buffer_iter_backward_to_context_class_toggle (GtkSourceBuffer *buffer
        }
 }
 
-static void
+static gchar *
 do_lower_case (GtkTextBuffer     *buffer,
               const GtkTextIter *start,
-              const GtkTextIter *end,
-              GString           *str)
+              const GtkTextIter *end)
 {
-       GtkTextIter iter = *start;
-
-       while (!gtk_text_iter_is_end (&iter) &&
-              !gtk_text_iter_equal (&iter, end))
-       {
-               gunichar c, nc;
+       gchar *text;
+       gchar *new_text;
 
-               c = gtk_text_iter_get_char (&iter);
-               nc = g_unichar_tolower (c);
-               g_string_append_unichar (str, nc);
+       text = gtk_text_buffer_get_text (buffer, start, end, TRUE);
+       new_text = g_utf8_strdown (text, -1);
 
-               gtk_text_iter_forward_char (&iter);
-       }
+       g_free (text);
+       return new_text;
 }
 
-static void
+static gchar *
 do_upper_case (GtkTextBuffer     *buffer,
               const GtkTextIter *start,
-              const GtkTextIter *end,
-              GString           *str)
+              const GtkTextIter *end)
 {
-       GtkTextIter iter = *start;
-
-       while (!gtk_text_iter_is_end (&iter) &&
-              !gtk_text_iter_equal (&iter, end))
-       {
-               gunichar c, nc;
+       gchar *text;
+       gchar *new_text;
 
-               c = gtk_text_iter_get_char (&iter);
-               nc = g_unichar_toupper (c);
-               g_string_append_unichar (str, nc);
+       text = gtk_text_buffer_get_text (buffer, start, end, TRUE);
+       new_text = g_utf8_strup (text, -1);
 
-               gtk_text_iter_forward_char (&iter);
-       }
+       g_free (text);
+       return new_text;
 }
 
-static void
+static gchar *
 do_toggle_case (GtkTextBuffer     *buffer,
                const GtkTextIter *start,
-               const GtkTextIter *end,
-               GString           *str)
+               const GtkTextIter *end)
 {
-       GtkTextIter iter = *start;
+       GString *str;
+       GtkTextIter iter_start;
 
-       while (!gtk_text_iter_is_end (&iter) &&
-              !gtk_text_iter_equal (&iter, end))
+       str = g_string_new (NULL);
+       iter_start = *start;
+
+       while (!gtk_text_iter_is_end (&iter_start))
        {
-               gunichar c, nc;
+               GtkTextIter iter_end;
+               gchar *text;
+               gchar *text_down;
+               gchar *text_up;
+
+               iter_end = iter_start;
+               gtk_text_iter_forward_cursor_position (&iter_end);
+
+               if (gtk_text_iter_compare (end, &iter_end) < 0)
+               {
+                       break;
+               }
+
+               text = gtk_text_buffer_get_text (buffer, &iter_start, &iter_end, TRUE);
+               text_down = g_utf8_strdown (text, -1);
+               text_up = g_utf8_strup (text, -1);
 
-               c = gtk_text_iter_get_char (&iter);
-               if (g_unichar_islower (c))
+               if (g_strcmp0 (text, text_down) == 0)
                {
-                       nc = g_unichar_toupper (c);
+                       g_string_append (str, text_up);
+               }
+               else if (g_strcmp0 (text, text_up) == 0)
+               {
+                       g_string_append (str, text_down);
                }
                else
                {
-                       nc = g_unichar_tolower (c);
+                       g_string_append (str, text);
                }
-               g_string_append_unichar (str, nc);
 
-               gtk_text_iter_forward_char (&iter);
+               g_free (text);
+               g_free (text_down);
+               g_free (text_up);
+
+               iter_start = iter_end;
        }
+
+       return g_string_free (str, FALSE);
 }
 
-static void
+static gchar *
 do_title_case (GtkTextBuffer     *buffer,
               const GtkTextIter *start,
-              const GtkTextIter *end,
-              GString           *str)
+              const GtkTextIter *end)
 {
-       GtkTextIter iter = *start;
+       GString *str;
+       GtkTextIter iter_start;
 
-       while (!gtk_text_iter_is_end (&iter) &&
-              !gtk_text_iter_equal (&iter, end))
+       str = g_string_new (NULL);
+       iter_start = *start;
+
+       while (!gtk_text_iter_is_end (&iter_start))
        {
-               gunichar c, nc;
+               GtkTextIter iter_end;
+               gchar *text;
+
+               iter_end = iter_start;
+               gtk_text_iter_forward_cursor_position (&iter_end);
 
-               c = gtk_text_iter_get_char (&iter);
-               if (gtk_text_iter_starts_word (&iter))
+               if (gtk_text_iter_compare (end, &iter_end) < 0)
                {
-                       nc = g_unichar_totitle (c);
+                       break;
+               }
+
+               text = gtk_text_buffer_get_text (buffer, &iter_start, &iter_end, TRUE);
+
+               if (gtk_text_iter_starts_word (&iter_start))
+               {
+                       gchar *text_normalized;
+
+                       text_normalized = g_utf8_normalize (text, -1, G_NORMALIZE_DEFAULT);
+
+                       if (g_utf8_strlen (text_normalized, -1) == 1)
+                       {
+                               gunichar c;
+                               gunichar new_c;
+
+                               c = gtk_text_iter_get_char (&iter_start);
+                               new_c = g_unichar_totitle (c);
+
+                               g_string_append_unichar (str, new_c);
+                       }
+                       else
+                       {
+                               gchar *text_up;
+
+                               text_up = g_utf8_strup (text, -1);
+                               g_string_append (str, text_up);
+
+                               g_free (text_up);
+                       }
+
+                       g_free (text_normalized);
                }
                else
                {
-                       nc = g_unichar_tolower (c);
+                       gchar *text_down;
+
+                       text_down = g_utf8_strdown (text, -1);
+                       g_string_append (str, text_down);
+
+                       g_free (text_down);
                }
-               g_string_append_unichar (str, nc);
 
-               gtk_text_iter_forward_char (&iter);
+               g_free (text);
+               iter_start = iter_end;
        }
+
+       return g_string_free (str, FALSE);
 }
 
 /**
@@ -2414,31 +2470,32 @@ gtk_source_buffer_change_case (GtkSourceBuffer         *buffer,
                                GtkTextIter             *end)
 {
        GtkTextBuffer *text_buffer;
-       GString *str;
+       gchar *new_text;
 
        g_return_if_fail (GTK_SOURCE_IS_BUFFER (buffer));
        g_return_if_fail (start != NULL);
        g_return_if_fail (end != NULL);
 
+       gtk_text_iter_order (start, end);
+
        text_buffer = GTK_TEXT_BUFFER (buffer);
-       str = g_string_new (NULL);
 
        switch (case_type)
        {
-               case GTK_SOURCE_CHANGE_CASE_UPPER:
-                       do_upper_case (text_buffer, start, end, str);
+               case GTK_SOURCE_CHANGE_CASE_LOWER:
+                       new_text = do_lower_case (text_buffer, start, end);
                        break;
 
-               case GTK_SOURCE_CHANGE_CASE_LOWER:
-                       do_lower_case (text_buffer, start, end, str);
+               case GTK_SOURCE_CHANGE_CASE_UPPER:
+                       new_text = do_upper_case (text_buffer, start, end);
                        break;
 
                case GTK_SOURCE_CHANGE_CASE_TOGGLE:
-                       do_toggle_case (text_buffer, start, end, str);
+                       new_text = do_toggle_case (text_buffer, start, end);
                        break;
 
                case GTK_SOURCE_CHANGE_CASE_TITLE:
-                       do_title_case (text_buffer, start, end, str);
+                       new_text = do_title_case (text_buffer, start, end);
                        break;
 
                default:
@@ -2446,11 +2503,11 @@ gtk_source_buffer_change_case (GtkSourceBuffer         *buffer,
        }
 
        gtk_text_buffer_begin_user_action (text_buffer);
-       gtk_text_buffer_delete_interactive (text_buffer, start, end, TRUE);
-       gtk_text_buffer_insert_interactive (text_buffer, start, str->str, str->len, TRUE);
+       gtk_text_buffer_delete (text_buffer, start, end);
+       gtk_text_buffer_insert (text_buffer, start, new_text, -1);
        gtk_text_buffer_end_user_action (text_buffer);
 
-       g_string_free (str, TRUE);
+       g_free (new_text);
 }
 
 /**
diff --git a/tests/test-buffer.c b/tests/test-buffer.c
index b2d34fc..cba7065 100644
--- a/tests/test-buffer.c
+++ b/tests/test-buffer.c
@@ -43,8 +43,8 @@ init_default_manager (void)
 static void
 test_get_buffer (void)
 {
-       GtkWidget* view;
-       GtkSourceBuffer* buffer;
+       GtkWidget *view;
+       GtkSourceBuffer *buffer;
 
        view = gtk_source_view_new ();
 
@@ -113,20 +113,32 @@ test_get_context_classes (void)
 
 static void
 do_test_change_case (GtkSourceBuffer         *buffer,
-                     GtkSourceChangeCaseType  case_type,
-                     const char              *text,
-                     const char              *expected)
+                    GtkSourceChangeCaseType  case_type,
+                    const gchar             *text,
+                    const gchar             *expected)
 {
-       GtkTextIter start, end;
-       char *changed;
+       GtkTextIter start;
+       GtkTextIter end;
+       gchar *changed;
+       gchar *changed_normalized;
+       gchar *expected_normalized;
 
        gtk_text_buffer_set_text (GTK_TEXT_BUFFER (buffer), text, -1);
+
        gtk_text_buffer_get_bounds (GTK_TEXT_BUFFER (buffer), &start, &end);
        gtk_source_buffer_change_case (buffer, case_type, &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);
+
+       changed_normalized = g_utf8_normalize (changed, -1, G_NORMALIZE_DEFAULT);
+       expected_normalized = g_utf8_normalize (expected, -1, G_NORMALIZE_DEFAULT);
+
+       g_assert_cmpstr (changed_normalized, ==, expected_normalized);
+
        g_free (changed);
+       g_free (changed_normalized);
+       g_free (expected_normalized);
 }
 
 static void
@@ -141,6 +153,24 @@ test_change_case (void)
        do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TOGGLE, "some TEXT", "SOME text");
        do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TITLE, "some TEXT", "Some Text");
 
+       /* https://bugzilla.gnome.org/show_bug.cgi?id=416390 */
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_LOWER, "T̈OME", "ẗome");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_UPPER, "ẗome", "T̈OME");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TOGGLE, "ẗome", "T̈OME");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TOGGLE, "T̈OME", "ẗome");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TITLE, "ẗome", "T̈ome");
+
+       /* test g_unichar_totitle */
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_LOWER, "\307\261adzíki", "\307\263adzíki");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_LOWER, "\307\262adzíki", "\307\263adzíki");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_LOWER, "\307\263adzíki", "\307\263adzíki");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_UPPER, "\307\263adzíki", "\307\261ADZÍKI");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_UPPER, "\307\262adzíki", "\307\261ADZÍKI");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TOGGLE, "\307\263adzíki", "\307\261ADZÍKI");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TITLE, "\307\263adzíki", "\307\262adzíki");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TITLE, "\307\261ADZÍKI", "\307\262adzíki");
+       do_test_change_case (buffer, GTK_SOURCE_CHANGE_CASE_TITLE, "\307\262ADZÍKI", "\307\262adzíki");
+
        g_object_unref (buffer);
 }