Classify name takes const patterns into account

Author: matklad

crates/ra_ide/src/goto_definition.rs

@@ -30,7 +30,9 @@ pub(crate) fn goto_definition(
                 reference_definition(&sema, &name_ref).to_vec()
             },
             ast::Name(name) => {
-                name_definition(&sema, &name)?
+                let def = classify_name(&sema, &name)?.definition();
+                let nav = def.try_to_nav(sema.db)?;
+                vec![nav]
             },
             _ => return None,
         }
@@ -88,15 +90,6 @@ pub(crate) fn reference_definition(
     Approximate(navs)
 }
 
-fn name_definition(
-    sema: &Semantics<RootDatabase>,
-    name: &ast::Name,
-) -> Option<Vec<NavigationTarget>> {
-    let def = classify_name(sema, name)?;
-    let nav = def.try_to_nav(sema.db)?;
-    Some(vec![nav])
-}
-
 #[cfg(test)]
 mod tests {
     use test_utils::{assert_eq_text, covers};

crates/ra_ide/src/hover.rs

@@ -156,7 +156,7 @@ pub(crate) fn hover(db: &RootDatabase, position: FilePosition) -> Option<RangeIn
                 classify_name_ref(&sema, &name_ref).map(|d| (name_ref.syntax().clone(), d))
             },
             ast::Name(name) => {
-                classify_name(&sema, &name).map(|d| (name.syntax().clone(), d))
+                classify_name(&sema, &name).map(|d| (name.syntax().clone(), d.definition()))
             },
             _ => None,
         }
@@ -761,13 +761,13 @@ fn func(foo: i32) { if true { <|>foo; }; }
     fn test_hover_through_literal_string_in_builtin_macro() {
         check_hover_no_result(
             r#"
-            //- /lib.rs            
+            //- /lib.rs
             #[rustc_builtin_macro]
             macro_rules! assert {
                 ($cond:expr) => {{ /* compiler built-in */ }};
                 ($cond:expr,) => {{ /* compiler built-in */ }};
                 ($cond:expr, $($arg:tt)+) => {{ /* compiler built-in */ }};
-            }        
+            }
 
             fn foo() {
                 assert!("hel<|>lo");

crates/ra_ide/src/references.rs

@@ -155,7 +155,7 @@ fn find_name(
     opt_name: Option<ast::Name>,
 ) -> Option<RangeInfo<(String, NameDefinition)>> {
     if let Some(name) = opt_name {
-        let def = classify_name(sema, &name)?;
+        let def = classify_name(sema, &name)?.definition();
         let range = name.syntax().text_range();
         return Some(RangeInfo::new(range, (name.text().to_string(), def)));
     }

crates/ra_ide/src/syntax_highlighting.rs

@@ -7,7 +7,7 @@ mod tests;
 
 use hir::{Name, Semantics};
 use ra_ide_db::{
-    defs::{classify_name, NameDefinition},
+    defs::{classify_name, NameClass, NameDefinition},
     RootDatabase,
 };
 use ra_prof::profile;
@@ -169,19 +169,21 @@ fn highlight_element(
             let name = element.into_node().and_then(ast::Name::cast).unwrap();
             let name_kind = classify_name(sema, &name);
 
-            if let Some(NameDefinition::Local(local)) = &name_kind {
+            if let Some(NameClass::NameDefinition(NameDefinition::Local(local))) = &name_kind {
                 if let Some(name) = local.name(db) {
                     let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
                     *shadow_count += 1;
                     binding_hash = Some(calc_binding_hash(&name, *shadow_count))
                 }
             };
 
-            let h = match name_kind {
-                Some(name_kind) => highlight_name(db, name_kind),
-                None => highlight_name_by_syntax(name),
-            };
-            h | HighlightModifier::Definition
+            match name_kind {
+                Some(NameClass::NameDefinition(def)) => {
+                    highlight_name(db, def) | HighlightModifier::Definition
+                }
+                Some(NameClass::ConstReference(def)) => highlight_name(db, def),
+                None => highlight_name_by_syntax(name) | HighlightModifier::Definition,
+            }
         }
 
         // Highlight references like the definitions they resolve to

crates/ra_ide_db/src/defs.rs

@@ -68,7 +68,32 @@ impl NameDefinition {
     }
 }
 
-pub fn classify_name(sema: &Semantics<RootDatabase>, name: &ast::Name) -> Option<NameDefinition> {
+pub enum NameClass {
+    NameDefinition(NameDefinition),
+    /// `None` in `if let None = Some(82) {}`
+    ConstReference(NameDefinition),
+}
+
+impl NameClass {
+    pub fn into_definition(self) -> Option<NameDefinition> {
+        match self {
+            NameClass::NameDefinition(it) => Some(it),
+            NameClass::ConstReference(_) => None,
+        }
+    }
+
+    pub fn definition(self) -> NameDefinition {
+        match self {
+            NameClass::NameDefinition(it) | NameClass::ConstReference(it) => it,
+        }
+    }
+}
+
+pub fn classify_name(sema: &Semantics<RootDatabase>, name: &ast::Name) -> Option<NameClass> {
+    classify_name_inner(sema, name).map(NameClass::NameDefinition)
+}
+
+fn classify_name_inner(sema: &Semantics<RootDatabase>, name: &ast::Name) -> Option<NameDefinition> {
     let _p = profile("classify_name");
     let parent = name.syntax().parent()?;
 

crates/ra_ide_db/src/imports_locator.rs

@@ -59,6 +59,7 @@ impl<'a> ImportsLocator<'a> {
         } else {
             candidate_node
         };
-        classify_name(&self.sema, &ast::Name::cast(candidate_name_node)?)
+        let name = ast::Name::cast(candidate_name_node)?;
+        classify_name(&self.sema, &name)?.into_definition()
     }
 }