crates/ide/src/inlay_hints/implicit_static.rs

   1 use either::Either;
   2 use syntax::{
   3     ast::{self, AstNode},
   4     SyntaxKind,
   5 };
   6
   7 use crate::{InlayHint, InlayHintsConfig, InlayKind, InlayTooltip, LifetimeElisionHints};
   8
   9 pub(super) fn hints(
  10     acc: &mut Vec<InlayHint>,
  11     config: &InlayHintsConfig,
  12     statik_or_const: Either<ast::Static, ast::Const>,
  13 ) -> Option<()> {
  14     if config.lifetime_elision_hints != LifetimeElisionHints::Always {
  15         return None;
  16     }
  17
  18     if let Either::Right(it) = &statik_or_const {
  19         if ast::AssocItemList::can_cast(
  20             it.syntax().parent().map_or(SyntaxKind::EOF, |it| it.kind()),
  21         ) {
  22             return None;
  23         }
  24     }
  25
  26     if let Some(ast::Type::RefType(ty)) = statik_or_const.either(|it| it.ty(), |it| it.ty()) {
  27         if ty.lifetime().is_none() {
  28             let t = ty.amp_token()?;
  29             acc.push(InlayHint {
  30                 range: t.text_range(),
  31                 kind: InlayKind::LifetimeHint,
  32                 label: "'static".to_owned().into(),
  33                 tooltip: Some(InlayTooltip::String("Elided static lifetime".into())),
  34             });
  35         }
  36     }
  37
  38     Some(())
  39 }
  40
  41 #[cfg(test)]
  42 mod tests {
  43     use crate::{
  44         inlay_hints::tests::{check_with_config, TEST_CONFIG},
  45         InlayHintsConfig, LifetimeElisionHints,
  46     };
  47
  48     #[test]
  49     fn hints_lifetimes_static() {
  50         check_with_config(
  51             InlayHintsConfig {
  52                 lifetime_elision_hints: LifetimeElisionHints::Always,
  53                 ..TEST_CONFIG
  54             },
  55             r#"
  56 trait Trait {}
  57 static S: &str = "";
  58 //        ^'static
  59 const C: &str = "";
  60 //       ^'static
  61 const C: &dyn Trait = panic!();
  62 //       ^'static
  63
  64 impl () {
  65     const C: &str = "";
  66     const C: &dyn Trait = panic!();
  67 }
  68 "#,
  69         );
  70     }
  71 }