xmlgen fails to generate rust code for Suse Snapper

I am trying to generate Rust code for Suse's snapper tool:

> busctl --xml-interface introspect org.opensuse.Snapper /org/opensuse/Snapper > snapper.xml
> zbus-xmlgen snapper.xml

Getting many errors like:

error: expected one of `:` or `@`, found `-`
  --> <stdin>:26:42
   |
26 |     fn calculate_used_space(&self, config-name: &str) -> zbus::Result<()>;
   |                                          ^ expected one of `:` or `@`

error: expected one of `:` or `@`, found `-`
  --> <stdin>:29:39
   |
29 |     fn create_comparison(&self, config-name: &str, number1: u32, number2: u32) -> zbus::Result<u32>;
   |                                       ^ expected one of `:` or `@`

error: expected one of `:` or `@`, found `-`
  --> <stdin>:32:35
   |
32 |     fn create_config(&self, config-name: &str, subvolume: &str, fstype: &str, template-name: &str) -> zbus::Result<()>;
   |                                   ^ expected one of `:` or `@`

error: expected one of `:` or `@`, found `-`
  --> <stdin>:32:87
   |
32 |     fn create_config(&self, config-name: &str, subvolume: &str, fstype: &str, template-name: &str) -> zbus::Result<()>;
   |                                                                                       ^ expected one of `:` or `@`

error: expected one of `:` or `@`, found `-`
  --> <stdin>:35:42
   |
35 |     fn create_post_snapshot(&self, config-name: &str, pre-number: u32, description: &str, cleanup: &str, userdata: std::collections::HashMap<&str, &str>) -> zbus::Result<u32>;
   |                                          ^ expected one of `:` or `@`

error: expected one of `:` or `@`, found `-`
  --> <stdin>:35:58
   |
35 |     fn create_post_snapshot(&self, config-name: &str, pre-number: u32, description: &str, cleanup: &str, userdata: std::collections::HashMap<&str, &str>) -> zbus::Result<u32>;
   |                                                          ^ expected one of `:` or `@`

error: expected one of `:` or `@`, found `-`
  --> <stdin>:38:41
   |
38 |     fn create_pre_snapshot(&self, config-name: &str, description: &str, cleanup: &str, userdata: std::collections::HashMap<&str, &str>) -> zbus::Result<u32>;
   |                                         ^ expected one of `:` or `@`

<the rest are omitted but very similar>

Please note, this happens even when i try to use the xml generated by zbus-xmlgen.

To reproduce the issue all you need is to have snapper installed through any package manager.

Please help me, i can give any further help if needed.