Add exception reporting in filter mode

src/main.cc

@@ -397,32 +397,46 @@ int run_filter(StringView keystr, memoryview<StringView> files)
     register_env_vars();
     register_registers();
 
+    try
+    {
         auto keys = parse_keys(keystr);
 
+        auto apply_keys_to_buffer = [&](Buffer& buffer)
+        {
+            try
+            {
+                InputHandler input_handler{{ buffer, Selection{} }};
+
+                for (auto& key : keys)
+                    input_handler.handle_key(key);
+            }
+            catch (Kakoune::runtime_error& err)
+            {
+                fprintf(stderr, "error while applying keys to buffer '%s': %s\n",
+                        buffer.display_name().c_str(), err.what());
+            }
+        };
+
         for (auto& file : files)
         {
             Buffer* buffer = create_buffer_from_file(file);
-        InputHandler input_handler{{ *buffer, Selection{} }};
+            apply_keys_to_buffer(*buffer);
-
-        for (auto& key : keys)
-            input_handler.handle_key(key);
-
             write_buffer_to_file(*buffer, file + ".kak-out");
-
             buffer_manager.delete_buffer(*buffer);
         }
         if (not isatty(0))
         {
-        Buffer* buffer = create_buffer_from_data(read_fd(0), "*stdin*", Buffer::Flags::None);
+            Buffer* buffer = create_buffer_from_data(read_fd(0), "*stdin*",
-        InputHandler input_handler{{ *buffer, Selection{} }};
+                                                     Buffer::Flags::None);
-
+            apply_keys_to_buffer(*buffer);
-        for (auto& key : keys)
-            input_handler.handle_key(key);
-
             write_buffer_to_fd(*buffer, 1);
-
             buffer_manager.delete_buffer(*buffer);
         }
+    }
+    catch (Kakoune::runtime_error& err)
+    {
+        fprintf(stderr, "error: %s\n", err.what());
+    }
 
     buffer_manager.clear_buffer_trash();
     return 0;