Merge #11481

[rust.git] / crates / ide_assists / src / handlers / generate_function.rs

diff --git a/crates/ide_assists/src/handlers/generate_function.rs b/crates/ide_assists/src/handlers/generate_function.rs
index baf956355105a3c7cb24e92d5e6e4ad99032eb9f..ac33d56858c03e89b1c354d7b870525d4fd6af0f 100644 (file)
--- a/crates/ide_assists/src/handlers/generate_function.rs
+++ b/crates/ide_assists/src/handlers/generate_function.rs
@@ -1,11 +1,13 @@
-use hir::{HasSource, HirDisplay, Module, ModuleDef, Semantics, TypeInfo};
+use rustc_hash::{FxHashMap, FxHashSet};
+
+use hir::{HasSource, HirDisplay, Module, Semantics, TypeInfo};
+use ide_db::helpers::FamousDefs;
 use ide_db::{
     base_db::FileId,
     defs::{Definition, NameRefClass},
     helpers::SnippetCap,
     RootDatabase,
 };
-use rustc_hash::{FxHashMap, FxHashSet};
 use stdx::to_lower_snake_case;
 use syntax::{
     ast::{
@@ -17,7 +19,7 @@
 };
 
 use crate::{
-    utils::useless_type_special_case,
+    utils::convert_reference_type,
     utils::{find_struct_impl, render_snippet, Cursor},
     AssistContext, AssistId, AssistKind, Assists,
 };
@@ -109,6 +111,10 @@ fn gen_fn(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
 
 fn gen_method(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
     let call: ast::MethodCallExpr = ctx.find_node_at_offset()?;
+    if ctx.sema.resolve_method_call(&call).is_some() {
+        return None;
+    }
+
     let fn_name = call.name_ref()?;
     let adt = ctx.sema.type_of_expr(&call.receiver()?)?.original().strip_references().as_adt()?;
 
@@ -364,7 +370,7 @@ fn get_fn_target(
     target_module: &Option<Module>,
     call: CallExpr,
 ) -> Option<(GeneratedFunctionTarget, FileId, TextSize)> {
-    let mut file = ctx.frange.file_id;
+    let mut file = ctx.file_id();
     let target = match target_module {
         Some(target_module) => {
             let module_source = target_module.definition_source(ctx.db());
@@ -424,19 +430,7 @@ fn fn_args(
     let mut arg_types = Vec::new();
     for arg in call.arg_list()?.args() {
         arg_names.push(fn_arg_name(&ctx.sema, &arg));
-        arg_types.push(match fn_arg_type(ctx, target_module, &arg) {
-            Some(ty) => {
-                if !ty.is_empty() && ty.starts_with('&') {
-                    match useless_type_special_case("", &ty[1..].to_owned()) {
-                        Some((new_ty, _)) => new_ty,
-                        None => ty,
-                    }
-                } else {
-                    ty
-                }
-            }
-            None => String::from("_"),
-        });
+        arg_types.push(fn_arg_type(ctx, target_module, &arg));
     }
     deduplicate_arg_names(&mut arg_names);
     let params = arg_names.into_iter().zip(arg_types).map(|(name, ty)| {
@@ -466,10 +460,10 @@ fn fn_args(
 /// assert_eq!(names, expected);
 /// ```
 fn deduplicate_arg_names(arg_names: &mut Vec<String>) {
-    let arg_name_counts = arg_names.iter().fold(FxHashMap::default(), |mut m, name| {
-        *m.entry(name).or_insert(0) += 1;
-        m
-    });
+    let mut arg_name_counts = FxHashMap::default();
+    for name in arg_names.iter() {
+        *arg_name_counts.entry(name).or_insert(0) += 1;
+    }
     let duplicate_arg_names: FxHashSet<String> = arg_name_counts
         .into_iter()
         .filter(|(_, count)| *count >= 2)
@@ -491,10 +485,14 @@ fn fn_arg_name(sema: &Semantics<RootDatabase>, arg_expr: &ast::Expr) -> String {
     let name = (|| match arg_expr {
         ast::Expr::CastExpr(cast_expr) => Some(fn_arg_name(sema, &cast_expr.expr()?)),
         expr => {
-            let name_ref = expr.syntax().descendants().filter_map(ast::NameRef::cast).last()?;
-            if let Some(NameRefClass::Definition(Definition::ModuleDef(
-                ModuleDef::Const(_) | ModuleDef::Static(_),
-            ))) = NameRefClass::classify(sema, &name_ref)
+            let name_ref = expr
+                .syntax()
+                .descendants()
+                .filter_map(ast::NameRef::cast)
+                .filter(|name| name.ident_token().is_some())
+                .last()?;
+            if let Some(NameRefClass::Definition(Definition::Const(_) | Definition::Static(_))) =
+                NameRefClass::classify(sema, &name_ref)
             {
                 return Some(name_ref.to_string().to_lowercase());
             };
@@ -511,17 +509,28 @@ fn fn_arg_name(sema: &Semantics<RootDatabase>, arg_expr: &ast::Expr) -> String {
     }
 }
 
-fn fn_arg_type(
-    ctx: &AssistContext,
-    target_module: hir::Module,
-    fn_arg: &ast::Expr,
-) -> Option<String> {
-    let ty = ctx.sema.type_of_expr(fn_arg)?.adjusted();
-    if ty.is_unknown() {
-        return None;
+fn fn_arg_type(ctx: &AssistContext, target_module: hir::Module, fn_arg: &ast::Expr) -> String {
+    fn maybe_displayed_type(
+        ctx: &AssistContext,
+        target_module: hir::Module,
+        fn_arg: &ast::Expr,
+    ) -> Option<String> {
+        let ty = ctx.sema.type_of_expr(fn_arg)?.adjusted();
+        if ty.is_unknown() {
+            return None;
+        }
+
+        if ty.is_reference() || ty.is_mutable_reference() {
+            let famous_defs = &FamousDefs(&ctx.sema, ctx.sema.scope(fn_arg.syntax()).krate());
+            convert_reference_type(ty.strip_references(), ctx.db(), famous_defs)
+                .map(|conversion| conversion.convert_type(ctx.db()))
+                .or_else(|| ty.display_source_code(ctx.db(), target_module.into()).ok())
+        } else {
+            ty.display_source_code(ctx.db(), target_module.into()).ok()
+        }
     }
 
-    ty.display_source_code(ctx.db(), target_module.into()).ok()
+    maybe_displayed_type(ctx, target_module, fn_arg).unwrap_or_else(|| String::from("_"))
 }
 
 /// Returns the position inside the current mod or file
@@ -1660,7 +1669,7 @@ fn main() {
     foo(a.0);
 }
 
-fn foo(arg0: ()) ${0:-> _} {
+fn foo(a: ()) ${0:-> _} {
     todo!()
 }
 ",