[gtksourceview] Apply context class tags directly after analysis

[Jesse van den Kieboom <jessevdk src gnome org>]

commit dc071301dd83c85cc0a0a18b9cc99ce260db3dc6
Author: Jesse van den Kieboom <jesse vandenkieboom epfl ch>
Date:   Sat Jan 2 16:29:05 2010 +0100

    Apply context class tags directly after analysis
    
    Before context class tags were applied at the same time as
    the highlighting was done, which causes many problems because
    context classes are also very relevant for parts of the buffer you
    don't see.

 gtksourceview/gtksourcecontextengine.c |  363 +++++++++++++++++++++-----------
 1 files changed, 238 insertions(+), 125 deletions(-)
---
diff --git a/gtksourceview/gtksourcecontextengine.c b/gtksourceview/gtksourcecontextengine.c
index 4b00887..29a0be0 100644
--- a/gtksourceview/gtksourcecontextengine.c
+++ b/gtksourceview/gtksourcecontextengine.c
@@ -609,18 +609,6 @@ unhighlight_region_cb (G_GNUC_UNUSED gpointer style,
 }
 
 static void
-unhighlight_region_class_cb (G_GNUC_UNUSED gpointer class,
-                             GtkTextTag             *tag,
-                             gpointer                user_data)
-{
-	struct BufAndIters *data = user_data;
-	gtk_text_buffer_remove_tag (data->buffer,
-	                            tag,
-	                            data->start,
-	                            data->end);
-}
-
-static void
 unhighlight_region (GtkSourceContextEngine *ce,
 		    const GtkTextIter      *start,
 		    const GtkTextIter      *end)
@@ -635,7 +623,6 @@ unhighlight_region (GtkSourceContextEngine *ce,
 		return;
 
 	g_hash_table_foreach (ce->priv->tags, (GHFunc) unhighlight_region_cb, &data);
-	g_hash_table_foreach (ce->priv->context_classes, (GHFunc) unhighlight_region_class_cb, &data);
 }
 
 #define MAX_STYLE_DEPENDENCY_DEPTH	50
@@ -831,6 +818,173 @@ get_context_tag (GtkSourceContextEngine *ce,
 	return context->tag;
 }
 
+static void
+apply_tags (GtkSourceContextEngine *ce,
+	    Segment                *segment,
+	    gint                    start_offset,
+	    gint                    end_offset)
+{
+	GtkTextTag *tag;
+	GtkTextIter start_iter, end_iter;
+	GtkTextBuffer *buffer = ce->priv->buffer;
+	SubPattern *sp;
+	Segment *child;
+
+	g_assert (segment != NULL);
+
+	if (SEGMENT_IS_INVALID (segment))
+		return;
+
+	if (segment->start_at >= end_offset || segment->end_at <= start_offset)
+		return;
+
+	start_offset = MAX (start_offset, segment->start_at);
+	end_offset = MIN (end_offset, segment->end_at);
+
+	tag = get_context_tag (ce, segment->context);
+
+	if (tag != NULL)
+	{
+		gint style_start_at, style_end_at;
+
+		style_start_at = start_offset;
+		style_end_at = end_offset;
+
+		if (HAS_OPTION (segment->context->definition, STYLE_INSIDE))
+		{
+			style_start_at = MAX (segment->start_at + segment->start_len, start_offset);
+			style_end_at = MIN (segment->end_at - segment->end_len, end_offset);
+		}
+
+		if (style_start_at > style_end_at)
+		{
+			g_critical ("%s: oops", G_STRLOC);
+		}
+		else
+		{
+			gtk_text_buffer_get_iter_at_offset (buffer, &start_iter, style_start_at);
+			end_iter = start_iter;
+			gtk_text_iter_forward_chars (&end_iter, style_end_at - style_start_at);
+			gtk_text_buffer_apply_tag (ce->priv->buffer, tag, &start_iter, &end_iter);
+		}
+	}
+
+	for (sp = segment->sub_patterns; sp != NULL; sp = sp->next)
+	{
+		if (sp->start_at >= start_offset && sp->end_at <= end_offset)
+		{
+			gint start = MAX (start_offset, sp->start_at);
+			gint end = MIN (end_offset, sp->end_at);
+
+			tag = get_subpattern_tag (ce, segment->context, sp->definition);
+
+			if (tag != NULL)
+			{
+				gtk_text_buffer_get_iter_at_offset (buffer, &start_iter, start);
+				end_iter = start_iter;
+				gtk_text_iter_forward_chars (&end_iter, end - start);
+				gtk_text_buffer_apply_tag (ce->priv->buffer, tag, &start_iter, &end_iter);
+			}
+		}
+	}
+
+	for (child = segment->children;
+	     child != NULL && child->start_at < end_offset;
+	     child = child->next)
+	{
+		if (child->end_at > start_offset)
+			apply_tags (ce, child, start_offset, end_offset);
+	}
+}
+
+/**
+ * highlight_region:
+ *
+ * @ce: a #GtkSourceContextEngine.
+ * @start: the beginning of the region to highlight.
+ * @end: the end of the region to highlight.
+ *
+ * Highlights the specified region.
+ */
+static void
+highlight_region (GtkSourceContextEngine *ce,
+		  GtkTextIter            *start,
+		  GtkTextIter            *end)
+{
+#ifdef ENABLE_PROFILE
+	GTimer *timer;
+#endif
+
+	if (gtk_text_iter_starts_line (end))
+		gtk_text_iter_backward_char (end);
+	if (gtk_text_iter_compare (start, end) >= 0)
+		return;
+
+#ifdef ENABLE_PROFILE
+	timer = g_timer_new ();
+#endif
+
+	/* First we need to delete tags in the regions. */
+	unhighlight_region (ce, start, end);
+
+	apply_tags (ce, ce->priv->root_segment,
+		    gtk_text_iter_get_offset (start),
+		    gtk_text_iter_get_offset (end));
+
+#ifdef ENABLE_PROFILE
+	g_print ("highlight (from %d to %d), %g ms elapsed\n",
+		 gtk_text_iter_get_offset (start),
+		 gtk_text_iter_get_offset (end),
+		 g_timer_elapsed (timer, NULL) * 1000);
+	g_timer_destroy (timer);
+#endif
+}
+
+/**
+ * ensure_highlighted:
+ *
+ * @ce: a #GtkSourceContextEngine.
+ * @start: the beginning of the region to highlight.
+ * @end: the end of the region to highlight.
+ *
+ * Updates text tags in reanalyzed parts of given area.
+ * It applies tags according to whatever is in the syntax
+ * tree currently, so highlighting may not be correct
+ * (gtk_source_context_engine_update_highlight is the method
+ * that actually ensures correct highlighting).
+ */
+static void
+ensure_highlighted (GtkSourceContextEngine *ce,
+		    const GtkTextIter      *start,
+		    const GtkTextIter      *end)
+{
+	GtkTextRegion *region;
+	GtkTextRegionIterator reg_iter;
+
+	/* Get the subregions not yet highlighted. */
+	region = gtk_text_region_intersect (ce->priv->refresh_region, start, end);
+
+	if (region == NULL)
+		return;
+
+	gtk_text_region_get_iterator (region, &reg_iter, 0);
+
+	/* Highlight all subregions from the intersection.
+	 * hopefully this will only be one subregion. */
+	while (!gtk_text_region_iterator_is_end (&reg_iter))
+	{
+		GtkTextIter s, e;
+		gtk_text_region_iterator_get_subregion (&reg_iter, &s, &e);
+		highlight_region (ce, &s, &e);
+		gtk_text_region_iterator_next (&reg_iter);
+	}
+
+	gtk_text_region_destroy (region, TRUE);
+
+	/* Remove the just highlighted region. */
+	gtk_text_region_subtract (ce->priv->refresh_region, start, end);
+}
+
 static GtkTextTag *
 get_context_class_tag (GtkSourceContextEngine *ce,
                        gchar const            *name)
@@ -944,14 +1098,11 @@ apply_context_classes (GtkSourceContextEngine *ce,
 }
 
 static void
-apply_tags (GtkSourceContextEngine *ce,
-	    Segment                *segment,
-	    gint                    start_offset,
-	    gint                    end_offset)
+add_region_context_classes (GtkSourceContextEngine *ce,
+                            Segment                *segment,
+                            gint                    start_offset,
+                            gint                    end_offset)
 {
-	GtkTextTag *tag;
-	GtkTextIter start_iter, end_iter;
-	GtkTextBuffer *buffer = ce->priv->buffer;
 	SubPattern *sp;
 	Segment *child;
 	GSList *context_classes;
@@ -959,10 +1110,14 @@ apply_tags (GtkSourceContextEngine *ce,
 	g_assert (segment != NULL);
 
 	if (SEGMENT_IS_INVALID (segment))
+	{
 		return;
+	}
 
 	if (segment->start_at >= end_offset || segment->end_at <= start_offset)
+	{
 		return;
+	}
 
 	start_offset = MAX (start_offset, segment->start_at);
 	end_offset = MIN (end_offset, segment->end_at);
@@ -978,34 +1133,6 @@ apply_tags (GtkSourceContextEngine *ce,
 		                       end_offset);
 	}
 
-	tag = get_context_tag (ce, segment->context);
-
-	if (tag != NULL)
-	{
-		gint style_start_at, style_end_at;
-
-		style_start_at = start_offset;
-		style_end_at = end_offset;
-
-		if (HAS_OPTION (segment->context->definition, STYLE_INSIDE))
-		{
-			style_start_at = MAX (segment->start_at + segment->start_len, start_offset);
-			style_end_at = MIN (segment->end_at - segment->end_len, end_offset);
-		}
-
-		if (style_start_at > style_end_at)
-		{
-			g_critical ("%s: oops", G_STRLOC);
-		}
-		else
-		{
-			gtk_text_buffer_get_iter_at_offset (buffer, &start_iter, style_start_at);
-			end_iter = start_iter;
-			gtk_text_iter_forward_chars (&end_iter, style_end_at - style_start_at);
-			gtk_text_buffer_apply_tag (ce->priv->buffer, tag, &start_iter, &end_iter);
-		}
-	}
-
 	for (sp = segment->sub_patterns; sp != NULL; sp = sp->next)
 	{
 		if (sp->start_at >= start_offset && sp->end_at <= end_offset)
@@ -1014,18 +1141,15 @@ apply_tags (GtkSourceContextEngine *ce,
 			gint end = MIN (end_offset, sp->end_at);
 
 			context_classes = get_subpattern_context_classes (ce,
-				                                          segment->context,
-				                                          sp->definition);
+			                                                  segment->context,
+			                                                  sp->definition);
 
-			tag = get_subpattern_tag (ce, segment->context, sp->definition);
-			apply_context_classes (ce, context_classes, start, end);
-
-			if (tag != NULL)
+			if (context_classes != NULL)
 			{
-				gtk_text_buffer_get_iter_at_offset (buffer, &start_iter, start);
-				end_iter = start_iter;
-				gtk_text_iter_forward_chars (&end_iter, end - start);
-				gtk_text_buffer_apply_tag (ce->priv->buffer, tag, &start_iter, &end_iter);
+				apply_context_classes (ce,
+				                       context_classes,
+				                       start,
+				                       end);
 			}
 		}
 	}
@@ -1035,99 +1159,85 @@ apply_tags (GtkSourceContextEngine *ce,
 	     child = child->next)
 	{
 		if (child->end_at > start_offset)
-			apply_tags (ce, child, start_offset, end_offset);
+		{
+			add_region_context_classes (ce, child, start_offset, end_offset);
+		}
 	}
 }
 
-/**
- * highlight_region:
- *
- * @ce: a #GtkSourceContextEngine.
- * @start: the beginning of the region to highlight.
- * @end: the end of the region to highlight.
- *
- * Highlights the specified region.
- */
 static void
-highlight_region (GtkSourceContextEngine *ce,
-		  GtkTextIter            *start,
-		  GtkTextIter            *end)
+remove_region_context_class_cb (G_GNUC_UNUSED gpointer class,
+                                GtkTextTag             *tag,
+                                gpointer                user_data)
+{
+	struct BufAndIters *data = user_data;
+	gtk_text_buffer_remove_tag (data->buffer,
+	                            tag,
+	                            data->start,
+	                            data->end);
+}
+
+static void
+remove_region_context_classes (GtkSourceContextEngine *ce,
+                               const GtkTextIter      *start,
+                               const GtkTextIter      *end)
+{
+	struct BufAndIters data;
+
+	data.buffer = ce->priv->buffer;
+	data.start = start;
+	data.end = end;
+
+	if (gtk_text_iter_equal (start, end))
+		return;
+
+	g_hash_table_foreach (ce->priv->context_classes,
+	                      (GHFunc) remove_region_context_class_cb,
+	                      &data);
+}
+
+static void
+refresh_context_classes (GtkSourceContextEngine *ce,
+                         const GtkTextIter      *start,
+                         const GtkTextIter      *end)
 {
 #ifdef ENABLE_PROFILE
 	GTimer *timer;
 #endif
+	GtkTextIter realend = *end;
 
-	if (gtk_text_iter_starts_line (end))
-		gtk_text_iter_backward_char (end);
-	if (gtk_text_iter_compare (start, end) >= 0)
+	if (gtk_text_iter_starts_line (&realend))
+	{
+		gtk_text_iter_backward_char (&realend);
+	}
+
+	if (gtk_text_iter_compare (start, &realend) >= 0)
+	{
 		return;
+	}
 
 #ifdef ENABLE_PROFILE
 	timer = g_timer_new ();
 #endif
 
 	/* First we need to delete tags in the regions. */
-	unhighlight_region (ce, start, end);
+	remove_region_context_classes (ce, start, &realend);
 
-	apply_tags (ce, ce->priv->root_segment,
-		    gtk_text_iter_get_offset (start),
-		    gtk_text_iter_get_offset (end));
+	add_region_context_classes (ce,
+	                            ce->priv->root_segment,
+	                            gtk_text_iter_get_offset (start),
+	                            gtk_text_iter_get_offset (&realend));
 
 #ifdef ENABLE_PROFILE
-	g_print ("highlight (from %d to %d), %g ms elapsed\n",
+	g_print ("applied context classes (from %d to %d), %g ms elapsed\n",
 		 gtk_text_iter_get_offset (start),
-		 gtk_text_iter_get_offset (end),
+		 gtk_text_iter_get_offset (&realend),
 		 g_timer_elapsed (timer, NULL) * 1000);
 	g_timer_destroy (timer);
 #endif
 }
 
 /**
- * ensure_highlighted:
- *
- * @ce: a #GtkSourceContextEngine.
- * @start: the beginning of the region to highlight.
- * @end: the end of the region to highlight.
- *
- * Updates text tags in reanalyzed parts of given area.
- * It applies tags according to whatever is in the syntax
- * tree currently, so highlighting may not be correct
- * (gtk_source_context_engine_update_highlight is the method
- * that actually ensures correct highlighting).
- */
-static void
-ensure_highlighted (GtkSourceContextEngine *ce,
-		    const GtkTextIter      *start,
-		    const GtkTextIter      *end)
-{
-	GtkTextRegion *region;
-	GtkTextRegionIterator reg_iter;
-
-	/* Get the subregions not yet highlighted. */
-	region = gtk_text_region_intersect (ce->priv->refresh_region, start, end);
-
-	if (region == NULL)
-		return;
-
-	gtk_text_region_get_iterator (region, &reg_iter, 0);
-
-	/* Highlight all subregions from the intersection.
-	 * hopefully this will only be one subregion. */
-	while (!gtk_text_region_iterator_is_end (&reg_iter))
-	{
-		GtkTextIter s, e;
-		gtk_text_region_iterator_get_subregion (&reg_iter, &s, &e);
-		highlight_region (ce, &s, &e);
-		gtk_text_region_iterator_next (&reg_iter);
-	}
-
-	gtk_text_region_destroy (region, TRUE);
-
-	/* Remove the just highlighted region. */
-	gtk_text_region_subtract (ce->priv->refresh_region, start, end);
-}
-
-/**
  * refresh_range:
  *
  * @ce: a #GtkSourceContextEngine.
@@ -1156,6 +1266,9 @@ refresh_range (GtkSourceContextEngine *ce,
 	if (modify_refresh_region)
 		gtk_text_region_add (ce->priv->refresh_region, start, end);
 
+	/* Refresh the contex classes here */
+	refresh_context_classes (ce, start, end);
+
 	/* Here we need to make sure we do not make it redraw next line */
 	real_end = *end;
 	if (gtk_text_iter_starts_line (&real_end))