fix escaping characters when printing mapping

Author: Remi-Gau

src/Mapping.m

@@ -225,19 +225,26 @@ function print_mapping(obj, filename)
                     input = obj.mapping(i);
                     input = prepare_for_printing(input);
 
+                    input_filename = input.filename;
+
                     %%
                     output = obj.mapping(i).name_spec;
                     output = prepare_for_printing(output);
 
-                    output.filename = ['*' output.filename];
+                    output_filename = output.filename;
+
+                    output_filename = ['*' output_filename];
+                    output_filename = strrep(output_filename, 'add-star', '*');
 
                     if fid ~= 1
-                        input.filename = strrep(input.filename, '*', '\*');
-                        output.filename = strrep(output.filename, '*', '\*');
+                        input_filename = strrep(input_filename, '*', '\*');
+                        input_filename = strrep(input_filename, '_', '\_');
+                        output_filename = strrep(output_filename, '*', '\*');
+                        output_filename = strrep(output_filename, '_', '\_');
                     end
 
                     fprintf(fid, '%s%s%s%s%s\n', ...
-                            left, input.filename, separator, output.filename, right);
+                            left, input_filename, separator, output_filename, right);
 
                 else
 
@@ -367,17 +374,21 @@ function print_mapping(obj, filename)
 
 function bf = prepare_for_printing(spec)
 
+    if isfield(spec, 'entities') && strcmp(spec.entities, '*')
+        spec.entities = struct('add', 'joker');
+    end
+    bf = bids.File(spec, 'tolerant', true);
+
     if isfield(spec, 'suffix') && isempty(spec.suffix) || ...
         ~isfield(spec, 'suffix')
-        spec.suffix = '*';
+        bf.suffix = '*';
     end
 
     if isfield(spec, 'ext') && ~isempty(spec.ext)
-        spec.extension = '.*';
+        bf.extension = '.*';
     end
     if ~isfield(spec, 'extension') || isempty(spec.extension)
-        spec.ext = '.*';
+        bf.extension = '.*';
     end
 
-    bf = bids.File(spec);
 end