lib: fix broken assert in FStream::opens

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>

diff --git a/lib/standard/file.nit b/lib/standard/file.nit
index 0b5fd04..5ff333c 100644 (file)
--- a/lib/standard/file.nit
+++ b/lib/standard/file.nit
@@ -117,7 +117,9 @@ class IFStream
                self.path = path
                prepare_buffer(10)
                _file = new NativeFile.io_open_read(path.to_cstring)
-               assert cant_open_file: _file != null
+               assert not _file.address_is_null else
+                       print "Error: Opening file at '{path}' failed with '{sys.errno.strerror}'"
+               end
        end
 
        private init do end
@@ -161,7 +163,9 @@ class OFStream
        init open(path: String)
        do
                _file = new NativeFile.io_open_write(path.to_cstring)
-               assert cant_open_file: _file != null
+               assert not _file.address_is_null else
+                       print "Error: Opening file at '{path}' failed with '{sys.errno.strerror}'"
+               end
                self.path = path
                _writable = true
        end