rapx/check/opt/data_collection/initialization/
vec_init.rs

1use annotate_snippets::{Level, Renderer, Snippet};
2
3use once_cell::sync::OnceCell;
4
5use rustc_hir::def_id::DefId;
6use rustc_middle::ty::TyCtxt;
7use rustc_span::Span;
8
9use crate::{
10    analysis::dataflow::*,
11    check::opt::OptCheck,
12    helpers::def_path::DefPath,
13    utils::log::{relative_pos_range, span_to_filename, span_to_line_number, span_to_source_code},
14};
15
16struct DefPaths {
17    vec_from_elem: DefPath,
18}
19
20static DEFPATHS: OnceCell<DefPaths> = OnceCell::new();
21
22impl DefPaths {
23    pub fn new(tcx: &TyCtxt<'_>) -> Self {
24        Self {
25            vec_from_elem: DefPath::new("std::vec::from_elem", tcx),
26        }
27    }
28
29    fn has_id(&self, def_id: DefId) -> bool {
30        def_id == self.vec_from_elem.last_def_id()
31    }
32}
33
34pub struct VecInitCheck {
35    record: Vec<Span>,
36}
37
38impl OptCheck for VecInitCheck {
39    fn new() -> Self {
40        Self { record: Vec::new() }
41    }
42
43    fn check(&mut self, graph: &Graph, tcx: &TyCtxt) {
44        let def_paths = &DEFPATHS.get_or_init(|| DefPaths::new(tcx));
45        for node in graph.nodes.iter() {
46            for op in node.ops.iter() {
47                if let NodeOp::Call(def_id) = op {
48                    if def_paths.has_id(*def_id) {
49                        self.record.push(node.span);
50                    }
51                }
52            }
53        }
54    }
55
56    fn report(&self, graph: &Graph) {
57        for span in self.record.iter() {
58            report_vec_init(graph, *span);
59        }
60    }
61
62    fn cnt(&self) -> usize {
63        self.record.len()
64    }
65}
66
67fn report_vec_init(graph: &Graph, span: Span) {
68    let code_source = span_to_source_code(graph.span);
69    let filename = span_to_filename(span);
70    let snippet = Snippet::source(&code_source)
71        .line_start(span_to_line_number(graph.span))
72        .origin(&filename)
73        .fold(true)
74        .annotation(
75            Level::Error
76                .span(relative_pos_range(graph.span, span))
77                .label("Initialization happens here"),
78        );
79    let message = Level::Warning
80        .title("Unnecessary data collection initialization detected")
81        .snippet(snippet)
82        .footer(Level::Help.title("Use unsafe APIs to skip initialization."));
83    let renderer = Renderer::styled();
84    rap_warn!("{}", renderer.render(message));
85}
rapx/check/opt/data_collection/initialization/vec_init.rs

rapx/check/opt/data_collection/initialization/
vec_init.rs
