Guard pageCount, chapterCount with exceptions

Author: mozbugbox

fitz/fitz.i

@@ -872,18 +872,34 @@ struct Document
             return doc;
         }
 
+        FITZEXCEPTION(pageCount, !result)
         CLOSECHECK0(pageCount, """Number of pages.""")
         %pythoncode%{@property%}
         PyObject *pageCount()
         {
-            return Py_BuildValue("i", fz_count_pages(gctx, (fz_document *) $self));
+            PyObject *ret;
+            fz_try(gctx) {
+                ret = Py_BuildValue("i", fz_count_pages(gctx, (fz_document *) $self));
+            }
+            fz_catch(gctx) {
+                return NULL;
+            }
+            return ret;
         }
 
+        FITZEXCEPTION(chapterCount, !result)
         CLOSECHECK0(chapterCount, """Number of chapters.""")
         %pythoncode%{@property%}
         PyObject *chapterCount()
         {
-            return Py_BuildValue("i", fz_count_chapters(gctx, (fz_document *) $self));
+            PyObject *ret;
+            fz_try(gctx) {
+                ret = Py_BuildValue("i", fz_count_chapters(gctx, (fz_document *) $self));
+            }
+            fz_catch(gctx) {
+                return NULL;
+            }
+            return ret;
         }
 
         FITZEXCEPTION(lastLocation, !result)
@@ -907,9 +923,9 @@ struct Document
         CLOSECHECK0(chapterPageCount, """Page count of chapter.""")
         PyObject *chapterPageCount(int chapter)
         {
-            int chapters = fz_count_chapters(gctx, (fz_document *) $self);
             int pages = 0;
             fz_try(gctx) {
+                int chapters = fz_count_chapters(gctx, (fz_document *) $self);
                 if (chapter < 0 || chapter >= chapters)
                     THROWMSG("bad chapter number");
                 pages = fz_count_chapter_pages(gctx, (fz_document *) $self, chapter);