i_slint_compiler/passes/
remove_unused_properties.rs

1// Copyright © SixtyFPS GmbH <info@slint.dev>
2// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0
3
4//! Remove the properties which are not used
5
6use crate::expression_tree::TwoWayBinding;
7use crate::object_tree::{Component, Document};
8use std::collections::HashSet;
9
10pub fn remove_unused_properties(doc: &Document) {
11    fn recurse_remove_unused_properties(component: &Component) {
12        crate::object_tree::recurse_elem_including_sub_components_no_borrow(
13            component,
14            &(),
15            &mut |elem, _| {
16                let mut elem = elem.borrow_mut();
17                let mut to_remove = HashSet::new();
18                for (prop, decl) in &elem.property_declarations {
19                    if !decl.expose_in_public_api
20                        && !elem.named_references.is_referenced(prop)
21                        && !elem.property_analysis.borrow().get(prop).is_some_and(|v| v.is_used())
22                        && !elem.change_callbacks.contains_key(prop)
23                        // Keep properties that carry model-data two-way bindings:
24                        // these bridge repeater data to other properties (e.g. globals)
25                        // and must survive for the interpreter to wire them up at runtime.
26                        && !elem.bindings.get(prop).is_some_and(|b| {
27                            b.borrow()
28                                .two_way_bindings
29                                .iter()
30                                .any(|t| matches!(t, TwoWayBinding::ModelData { .. }))
31                        })
32                    {
33                        to_remove.insert(prop.to_owned());
34                    }
35                }
36                for x in &to_remove {
37                    elem.property_declarations.remove(x);
38                    elem.property_analysis.borrow_mut().remove(x);
39                    elem.bindings.remove(x);
40                }
41                // Remove changed callbacks over properties that are not materialized as they are not used
42                let mut change_callbacks = std::mem::take(&mut elem.change_callbacks);
43                change_callbacks.retain(|prop, _| {
44                    super::materialize_fake_properties::has_declared_property(&elem, prop)
45                });
46                elem.change_callbacks = change_callbacks;
47            },
48        );
49    }
50    doc.visit_all_used_components(|component| recurse_remove_unused_properties(component))
51}
i_slint_compiler/passes/remove_unused_properties.rs

i_slint_compiler/passes/
remove_unused_properties.rs
