5345: Semantic Highlighting: Emit mutable modifier for 'self' when applicable r=matklad a=Veykril

This PR implements emitting the mutable modifier for the self keyword when applicable for semantic highlighting as mentioned in #5041. The rendered highlighting test html file:
![firefox_5lbsFNBqsT](https://user-images.githubusercontent.com/3757771/87346245-a5a07280-c551-11ea-9051-e5901255f8c9.png)
As you can see it does not emit the modifier when `self` is not used in a mutable context even if it is declared mutably in the enclosing function. I'm not sure if this is actually something wanted or not.

Co-authored-by: Lukas Wirth <lukastw97@gmail.com>
This commit is contained in:
bors[bot] 2020-07-15 10:00:10 +00:00 committed by GitHub
commit 6f3c8dc11d
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 44 additions and 3 deletions

View file

@ -566,10 +566,31 @@ fn highlight_element(
| T![return]
| T![while]
| T![in] => h | HighlightModifier::ControlFlow,
T![for] if !is_child_of_impl(element) => h | HighlightModifier::ControlFlow,
T![for] if !is_child_of_impl(&element) => h | HighlightModifier::ControlFlow,
T![unsafe] => h | HighlightModifier::Unsafe,
T![true] | T![false] => HighlightTag::BoolLiteral.into(),
T![self] => HighlightTag::SelfKeyword.into(),
T![self] => {
let self_param_is_mut = element
.parent()
.and_then(ast::SelfParam::cast)
.and_then(|p| p.mut_token())
.is_some();
// closure to enforce lazyness
let self_path = || {
sema.resolve_path(&element.parent()?.parent().and_then(ast::Path::cast)?)
};
if self_param_is_mut
|| matches!(self_path(),
Some(hir::PathResolution::Local(local))
if local.is_self(db)
&& (local.is_mut(db) || local.ty(db).is_mutable_reference())
)
{
HighlightTag::SelfKeyword | HighlightModifier::Mutable
} else {
HighlightTag::SelfKeyword.into()
}
}
_ => h,
}
}
@ -592,7 +613,7 @@ fn highlight_element(
}
}
fn is_child_of_impl(element: SyntaxElement) -> bool {
fn is_child_of_impl(element: &SyntaxElement) -> bool {
match element.parent() {
Some(e) => e.kind() == IMPL_DEF,
_ => false,

View file

@ -25,6 +25,16 @@ impl Bar for Foo {
}
}
impl Foo {
fn baz(mut self) -> i32 {
self.x
}
fn qux(&mut self) {
self.x = 0;
}
}
static mut STATIC_MUT: i32 = 0;
fn foo<'a, T>() -> T {

View file

@ -51,6 +51,16 @@ pre { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
}
}
<span class="keyword">impl</span> <span class="struct">Foo</span> {
<span class="keyword">fn</span> <span class="function declaration">baz</span>(<span class="keyword">mut</span> <span class="self_keyword mutable">self</span>) -&gt; <span class="builtin_type">i32</span> {
<span class="self_keyword">self</span>.<span class="field">x</span>
}
<span class="keyword">fn</span> <span class="function declaration">qux</span>(&<span class="keyword">mut</span> <span class="self_keyword mutable">self</span>) {
<span class="self_keyword mutable">self</span>.<span class="field">x</span> = <span class="numeric_literal">0</span>;
}
}
<span class="keyword">static</span> <span class="keyword">mut</span> <span class="static declaration mutable">STATIC_MUT</span>: <span class="builtin_type">i32</span> = <span class="numeric_literal">0</span>;
<span class="keyword">fn</span> <span class="function declaration">foo</span>&lt;<span class="lifetime declaration">'a</span>, <span class="type_param declaration">T</span>&gt;() -&gt; <span class="type_param">T</span> {