[gtk/matthiasc/for-master: 2/2] textbuffer: Improve some get_iter apis

[Matthias Clasen <matthiasc src gnome org>]

commit ac79c0e799457ac57cecfa38e8d45bef195b2cfd
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Oct 3 13:30:42 2020 -0400

    textbuffer: Improve some get_iter apis
    
    Make these functions return FALSE if they did not
    return the exact position that was requested.
    
    Adapt tests.
    
    Based on a patch by Sebastien Wilmet
    
    Fixes: #506

 gtk/gtktextbuffer.c        | 66 ++++++++++++++++++++++++++++------------------
 gtk/gtktextbuffer.h        | 34 ++++++++++++------------
 testsuite/gtk/textbuffer.c | 46 ++++++++++++++++----------------
 3 files changed, 80 insertions(+), 66 deletions(-)
---
diff --git a/gtk/gtktextbuffer.c b/gtk/gtktextbuffer.c
index 121813c54e..2e846785e7 100644
--- a/gtk/gtktextbuffer.c
+++ b/gtk/gtktextbuffer.c
@@ -3224,8 +3224,10 @@ gtk_text_buffer_remove_all_tags (GtkTextBuffer     *buffer,
  * If @line_number is greater than the number of lines
  * in the @buffer, the end iterator is returned. And if @char_offset is off the
  * end of the line, the iterator at the end of the line is returned.
+ *
+ * Returns: whether the exact position has been found
  **/
-void
+gboolean
 gtk_text_buffer_get_iter_at_line_offset (GtkTextBuffer *buffer,
                                          GtkTextIter   *iter,
                                          int            line_number,
@@ -3233,13 +3235,13 @@ gtk_text_buffer_get_iter_at_line_offset (GtkTextBuffer *buffer,
 {
   GtkTextIter end_line_iter;
 
-  g_return_if_fail (iter != NULL);
-  g_return_if_fail (GTK_IS_TEXT_BUFFER (buffer));
+  g_return_val_if_fail (iter != NULL, FALSE);
+  g_return_val_if_fail (GTK_IS_TEXT_BUFFER (buffer), FALSE);
 
   if (line_number >= gtk_text_buffer_get_line_count (buffer))
     {
       gtk_text_buffer_get_end_iter (buffer, iter);
-      return;
+      return FALSE;
     }
 
   _gtk_text_btree_get_iter_at_line_char (get_btree (buffer), iter, line_number, 0);
@@ -3248,16 +3250,20 @@ gtk_text_buffer_get_iter_at_line_offset (GtkTextBuffer *buffer,
   if (!gtk_text_iter_ends_line (&end_line_iter))
     gtk_text_iter_forward_to_line_end (&end_line_iter);
 
-  if (char_offset <= gtk_text_iter_get_line_offset (&end_line_iter))
-    gtk_text_iter_set_line_offset (iter, char_offset);
-  else
-    *iter = end_line_iter;
+  if (char_offset > gtk_text_iter_get_line_offset (&end_line_iter))
+    {
+      *iter = end_line_iter;
+      return FALSE;
+    }
+
+  gtk_text_iter_set_line_offset (iter, char_offset);
+  return TRUE;
 }
 
 /**
  * gtk_text_buffer_get_iter_at_line_index:
- * @buffer: a #GtkTextBuffer 
- * @iter: (out): iterator to initialize 
+ * @buffer: a #GtkTextBuffer
+ * @iter: (out): iterator to initialize
  * @line_number: line number counting from 0
  * @byte_index: byte index from start of line
  *
@@ -3268,8 +3274,10 @@ gtk_text_buffer_get_iter_at_line_offset (GtkTextBuffer *buffer,
  * If @line_number is greater than the number of lines
  * in the @buffer, the end iterator is returned. And if @byte_index is off the
  * end of the line, the iterator at the end of the line is returned.
+ *
+ * Returns: whether the exact position has been found
  **/
-void
+gboolean
 gtk_text_buffer_get_iter_at_line_index  (GtkTextBuffer *buffer,
                                          GtkTextIter   *iter,
                                          int            line_number,
@@ -3277,13 +3285,13 @@ gtk_text_buffer_get_iter_at_line_index  (GtkTextBuffer *buffer,
 {
   GtkTextIter end_line_iter;
 
-  g_return_if_fail (iter != NULL);
-  g_return_if_fail (GTK_IS_TEXT_BUFFER (buffer));
+  g_return_val_if_fail (iter != NULL, FALSE);
+  g_return_val_if_fail (GTK_IS_TEXT_BUFFER (buffer), FALSE);
 
   if (line_number >= gtk_text_buffer_get_line_count (buffer))
     {
       gtk_text_buffer_get_end_iter (buffer, iter);
-      return;
+      return FALSE;
     }
 
   gtk_text_buffer_get_iter_at_line (buffer, iter, line_number);
@@ -3292,35 +3300,41 @@ gtk_text_buffer_get_iter_at_line_index  (GtkTextBuffer *buffer,
   if (!gtk_text_iter_ends_line (&end_line_iter))
     gtk_text_iter_forward_to_line_end (&end_line_iter);
 
-  if (byte_index <= gtk_text_iter_get_line_index (&end_line_iter))
-    gtk_text_iter_set_line_index (iter, byte_index);
-  else
-    *iter = end_line_iter;
+  if (byte_index > gtk_text_iter_get_line_index (&end_line_iter))
+    {
+      *iter = end_line_iter;
+      return FALSE;
+    }
+
+  gtk_text_iter_set_line_index (iter, byte_index);
+  return TRUE;
 }
 
 /**
  * gtk_text_buffer_get_iter_at_line:
- * @buffer: a #GtkTextBuffer 
+ * @buffer: a #GtkTextBuffer
  * @iter: (out): iterator to initialize
  * @line_number: line number counting from 0
  *
  * Initializes @iter to the start of the given line. If @line_number is greater
  * than the number of lines in the @buffer, the end iterator is returned.
- **/
-void
+ *
+ * Returns: whether the exact position has been found
+ */
+gboolean
 gtk_text_buffer_get_iter_at_line (GtkTextBuffer *buffer,
                                   GtkTextIter   *iter,
                                   int            line_number)
 {
-  g_return_if_fail (iter != NULL);
-  g_return_if_fail (GTK_IS_TEXT_BUFFER (buffer));
+  g_return_val_if_fail (iter != NULL, FALSE);
+  g_return_val_if_fail (GTK_IS_TEXT_BUFFER (buffer), FALSE);
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, iter, line_number, 0);
+  return gtk_text_buffer_get_iter_at_line_offset (buffer, iter, line_number, 0);
 }
 
 /**
  * gtk_text_buffer_get_iter_at_offset:
- * @buffer: a #GtkTextBuffer 
+ * @buffer: a #GtkTextBuffer
  * @iter: (out): iterator to initialize
  * @char_offset: char offset from start of buffer, counting from 0, or -1
  *
@@ -3328,7 +3342,7 @@ gtk_text_buffer_get_iter_at_line (GtkTextBuffer *buffer,
  * of the entire buffer. If @char_offset is -1 or greater than the number
  * of characters in the buffer, @iter is initialized to the end iterator,
  * the iterator one past the last valid character in the buffer.
- **/
+ */
 void
 gtk_text_buffer_get_iter_at_offset (GtkTextBuffer *buffer,
                                     GtkTextIter   *iter,
diff --git a/gtk/gtktextbuffer.h b/gtk/gtktextbuffer.h
index 1c382bb7c5..c084ff838b 100644
--- a/gtk/gtktextbuffer.h
+++ b/gtk/gtktextbuffer.h
@@ -369,23 +369,23 @@ GtkTextTag    *gtk_text_buffer_create_tag (GtkTextBuffer *buffer,
  * iterator around using the GtkTextIter operators
  */
 GDK_AVAILABLE_IN_ALL
-void gtk_text_buffer_get_iter_at_line_offset (GtkTextBuffer *buffer,
-                                              GtkTextIter   *iter,
-                                              int            line_number,
-                                              int            char_offset);
-GDK_AVAILABLE_IN_ALL
-void gtk_text_buffer_get_iter_at_line_index  (GtkTextBuffer *buffer,
-                                              GtkTextIter   *iter,
-                                              int            line_number,
-                                              int            byte_index);
-GDK_AVAILABLE_IN_ALL
-void gtk_text_buffer_get_iter_at_offset      (GtkTextBuffer *buffer,
-                                              GtkTextIter   *iter,
-                                              int            char_offset);
-GDK_AVAILABLE_IN_ALL
-void gtk_text_buffer_get_iter_at_line        (GtkTextBuffer *buffer,
-                                              GtkTextIter   *iter,
-                                              int            line_number);
+gboolean gtk_text_buffer_get_iter_at_line_offset (GtkTextBuffer *buffer,
+                                                  GtkTextIter   *iter,
+                                                  int            line_number,
+                                                  int            char_offset);
+GDK_AVAILABLE_IN_ALL
+gboolean gtk_text_buffer_get_iter_at_line_index  (GtkTextBuffer *buffer,
+                                                  GtkTextIter   *iter,
+                                                  int            line_number,
+                                                  int            byte_index);
+GDK_AVAILABLE_IN_ALL
+void     gtk_text_buffer_get_iter_at_offset      (GtkTextBuffer *buffer,
+                                                  GtkTextIter   *iter,
+                                                  int            char_offset);
+GDK_AVAILABLE_IN_ALL
+gboolean gtk_text_buffer_get_iter_at_line        (GtkTextBuffer *buffer,
+                                                  GtkTextIter   *iter,
+                                                  int            line_number);
 GDK_AVAILABLE_IN_ALL
 void gtk_text_buffer_get_start_iter          (GtkTextBuffer *buffer,
                                               GtkTextIter   *iter);
diff --git a/testsuite/gtk/textbuffer.c b/testsuite/gtk/textbuffer.c
index b0a2e243c2..485571f568 100644
--- a/testsuite/gtk/textbuffer.c
+++ b/testsuite/gtk/textbuffer.c
@@ -1472,88 +1472,88 @@ test_get_iter (void)
   gtk_text_buffer_set_text (buffer, "ab\nßd\r\nef", -1);
 
   /* Test get_iter_at_line() */
-  gtk_text_buffer_get_iter_at_line (buffer, &iter, 0);
+  g_assert (gtk_text_buffer_get_iter_at_line (buffer, &iter, 0));
   g_assert (gtk_text_iter_is_start (&iter));
 
-  gtk_text_buffer_get_iter_at_line (buffer, &iter, 1);
+  g_assert (gtk_text_buffer_get_iter_at_line (buffer, &iter, 1));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 3);
 
-  gtk_text_buffer_get_iter_at_line (buffer, &iter, 2);
+  g_assert (gtk_text_buffer_get_iter_at_line (buffer, &iter, 2));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 7);
 
-  gtk_text_buffer_get_iter_at_line (buffer, &iter, 3);
+  g_assert (!gtk_text_buffer_get_iter_at_line (buffer, &iter, 3));
   g_assert (gtk_text_iter_is_end (&iter));
 
   /* Test get_iter_at_line_offset() */
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 0, 0);
+  g_assert (gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 0, 0));
   g_assert (gtk_text_iter_is_start (&iter));
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 0, 1);
+  g_assert (gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 0, 1));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 1);
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 0, 2);
+  g_assert (gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 0, 2));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 2);
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 0, 3);
+  g_assert (!gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 0, 3));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 2);
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 1, 1);
+  g_assert (gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 1, 1));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 4);
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 2, 1);
+  g_assert (gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 2, 1));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 8);
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 2, 2);
+  g_assert (gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 2, 2));
   g_assert (gtk_text_iter_is_end (&iter));
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 2, 3);
+  g_assert (!gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 2, 3));
   g_assert (gtk_text_iter_is_end (&iter));
 
-  gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 3, 1);
+  g_assert (!gtk_text_buffer_get_iter_at_line_offset (buffer, &iter, 3, 1));
   g_assert (gtk_text_iter_is_end (&iter));
 
   /* Test get_iter_at_line_index() */
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 0, 0);
+  g_assert (gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 0, 0));
   g_assert (gtk_text_iter_is_start (&iter));
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 0, 1);
+  g_assert (gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 0, 1));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 1);
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 0, 2);
+  g_assert (gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 0, 2));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 2);
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 0, 3);
+  g_assert (!gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 0, 3));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 2);
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 1, 0);
+  g_assert (gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 1, 0));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 3);
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 1, 2);
+  g_assert (gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 1, 2));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 4);
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 1, 3);
+  g_assert (gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 1, 3));
   offset = gtk_text_iter_get_offset (&iter);
   g_assert_cmpint (offset, ==, 5);
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 2, 2);
+  g_assert (gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 2, 2));
   g_assert (gtk_text_iter_is_end (&iter));
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 2, 3);
+  g_assert (!gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 2, 3));
   g_assert (gtk_text_iter_is_end (&iter));
 
-  gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 3, 1);
+  g_assert (!gtk_text_buffer_get_iter_at_line_index (buffer, &iter, 3, 1));
   g_assert (gtk_text_iter_is_end (&iter));
 
   /* Test get_iter_at_offset() */