nitdoc: assert valid key in redefinition of `provide_default_value`

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/src/doc/doc_phases/doc_indexing.nit b/src/doc/doc_phases/doc_indexing.nit
index 3e71df2..72df73c 100644 (file)
--- a/src/doc/doc_phases/doc_indexing.nit
+++ b/src/doc/doc_phases/doc_indexing.nit
@@ -80,6 +80,7 @@ private class QuickSearchTable
 
        redef fun provide_default_value(key) do
                var v = new QuickSearchResultList
+               assert key isa String
                self[key] = v
                return v
        end