diff --git a/crates/hir/src/has_source.rs b/crates/hir/src/has_source.rs
index 197149c5ebb..3a014545138 100644
--- a/crates/hir/src/has_source.rs
+++ b/crates/hir/src/has_source.rs
@@ -10,8 +10,8 @@ use hir_expand::InFile;
use syntax::ast;
use crate::{
- db::HirDatabase, Const, ConstParam, Enum, Field, FieldSource, Function, Impl, LifetimeParam,
- MacroDef, Module, Static, Struct, Trait, TypeAlias, TypeParam, Union, Variant,
+ db::HirDatabase, Adt, Const, ConstParam, Enum, Field, FieldSource, Function, Impl,
+ LifetimeParam, MacroDef, Module, Static, Struct, Trait, TypeAlias, TypeParam, Union, Variant,
};
pub trait HasSource {
@@ -56,6 +56,16 @@ impl HasSource for Field {
Some(field_source)
}
}
+impl HasSource for Adt {
+ type Ast = ast::Adt;
+ fn source(self, db: &dyn HirDatabase) -> Option<InFile<Self::Ast>> {
+ match self {
+ Adt::Struct(s) => Some(s.source(db)?.map(|s| ast::Adt::Struct(s))),
+ Adt::Union(u) => Some(u.source(db)?.map(|u| ast::Adt::Union(u))),
+ Adt::Enum(e) => Some(e.source(db)?.map(|e| ast::Adt::Enum(e))),
+ }
+ }
+}
impl HasSource for Struct {
type Ast = ast::Struct;
fn source(self, db: &dyn HirDatabase) -> Option<InFile<Self::Ast>> {
diff --git a/crates/ide_assists/src/handlers/add_missing_impl_members.rs b/crates/ide_assists/src/handlers/add_missing_impl_members.rs
index 59d5f48301b..a145598c791 100644
--- a/crates/ide_assists/src/handlers/add_missing_impl_members.rs
+++ b/crates/ide_assists/src/handlers/add_missing_impl_members.rs
@@ -1,10 +1,12 @@
+use hir::HasSource;
use ide_db::traits::resolve_target_trait;
-use syntax::ast::{self, AstNode};
+use syntax::ast::{self, make, AstNode};
use crate::{
assist_context::{AssistContext, Assists},
utils::{
- add_trait_assoc_items_to_impl, filter_assoc_items, render_snippet, Cursor, DefaultMethods,
+ add_trait_assoc_items_to_impl, filter_assoc_items, gen_trait_fn_body, render_snippet,
+ Cursor, DefaultMethods,
},
AssistId, AssistKind,
};
@@ -115,18 +117,26 @@ fn add_missing_impl_members_inner(
let target = impl_def.syntax().text_range();
acc.add(AssistId(assist_id, AssistKind::QuickFix), label, target, |builder| {
let target_scope = ctx.sema.scope(impl_def.syntax());
- let (new_impl_def, first_new_item) =
- add_trait_assoc_items_to_impl(&ctx.sema, missing_items, trait_, impl_def, target_scope);
+ let (new_impl_def, first_new_item) = add_trait_assoc_items_to_impl(
+ &ctx.sema,
+ missing_items,
+ trait_,
+ impl_def.clone(),
+ target_scope,
+ );
match ctx.config.snippet_cap {
None => builder.replace(target, new_impl_def.to_string()),
Some(cap) => {
let mut cursor = Cursor::Before(first_new_item.syntax());
let placeholder;
if let ast::AssocItem::Fn(func) = &first_new_item {
- if let Some(m) = func.syntax().descendants().find_map(ast::MacroCall::cast) {
- if m.syntax().text() == "todo!()" {
- placeholder = m;
- cursor = Cursor::Replace(placeholder.syntax());
+ if try_gen_trait_body(ctx, func, &trait_, &impl_def).is_none() {
+ if let Some(m) = func.syntax().descendants().find_map(ast::MacroCall::cast)
+ {
+ if m.syntax().text() == "todo!()" {
+ placeholder = m;
+ cursor = Cursor::Replace(placeholder.syntax());
+ }
}
}
}
@@ -140,6 +150,18 @@ fn add_missing_impl_members_inner(
})
}
+fn try_gen_trait_body(
+ ctx: &AssistContext,
+ func: &ast::Fn,
+ trait_: &hir::Trait,
+ impl_def: &ast::Impl,
+) -> Option<()> {
+ let trait_path = make::ext::ident_path(&trait_.name(ctx.db()).to_string());
+ let hir_ty = ctx.sema.resolve_type(&impl_def.self_ty()?)?;
+ let adt = hir_ty.as_adt()?.source(ctx.db())?;
+ gen_trait_fn_body(func, &trait_path, &adt.value)
+}
+
#[cfg(test)]
mod tests {
use crate::tests::{check_assist, check_assist_not_applicable};
@@ -847,4 +869,28 @@ impl T for () {
",
);
}
+
+ #[test]
+ fn test_default_body_generation() {
+ check_assist(
+ add_missing_impl_members,
+ r#"
+//- minicore: default
+struct Foo(usize);
+
+impl Default for Foo {
+ $0
+}
+"#,
+ r#"
+struct Foo(usize);
+
+impl Default for Foo {
+ $0fn default() -> Self {
+ Self(Default::default())
+ }
+}
+"#,
+ )
+ }
}
diff --git a/crates/ide_assists/src/handlers/replace_derive_with_manual_impl.rs b/crates/ide_assists/src/handlers/replace_derive_with_manual_impl.rs
index bcabca64b32..2add705db2e 100644
--- a/crates/ide_assists/src/handlers/replace_derive_with_manual_impl.rs
+++ b/crates/ide_assists/src/handlers/replace_derive_with_manual_impl.rs
@@ -2,8 +2,6 @@ use hir::ModuleDef;
use ide_db::helpers::{import_assets::NameToImport, mod_path_to_ast};
use ide_db::items_locator;
use itertools::Itertools;
-use syntax::ast::edit::AstNodeEdit;
-use syntax::ted;
use syntax::{
ast::{self, make, AstNode, NameOwner},
SyntaxKind::{IDENT, WHITESPACE},
@@ -12,8 +10,8 @@ use syntax::{
use crate::{
assist_context::{AssistBuilder, AssistContext, Assists},
utils::{
- add_trait_assoc_items_to_impl, filter_assoc_items, generate_trait_impl_text,
- render_snippet, Cursor, DefaultMethods,
+ add_trait_assoc_items_to_impl, filter_assoc_items, gen_trait_fn_body,
+ generate_trait_impl_text, render_snippet, Cursor, DefaultMethods,
},
AssistId, AssistKind,
};
@@ -169,158 +167,12 @@ fn impl_def_from_trait(
// Generate a default `impl` function body for the derived trait.
if let ast::AssocItem::Fn(ref func) = first_assoc_item {
- let _ = gen_trait_body_impl(func, trait_path, adt, annotated_name);
+ let _ = gen_trait_fn_body(func, trait_path, adt);
};
Some((impl_def, first_assoc_item))
}
-/// Generate custom trait bodies where possible.
-///
-/// Returns `Option` so that we can use `?` rather than `if let Some`. Returning
-/// `None` means that generating a custom trait body failed, and the body will remain
-/// as `todo!` instead.
-fn gen_trait_body_impl(
- func: &ast::Fn,
- trait_path: &ast::Path,
- adt: &ast::Adt,
- annotated_name: &ast::Name,
-) -> Option<()> {
- match trait_path.segment()?.name_ref()?.text().as_str() {
- "Debug" => gen_debug_impl(adt, func, annotated_name),
- "Default" => gen_default_impl(adt, func),
- _ => None,
- }
-}
-
-/// Generate a `Debug` impl based on the fields and members of the target type.
-fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn, annotated_name: &ast::Name) -> Option<()> {
- match adt {
- // `Debug` cannot be derived for unions, so no default impl can be provided.
- ast::Adt::Union(_) => None,
-
- // => match self { Self::Variant => write!(f, "Variant") }
- ast::Adt::Enum(enum_) => {
- let list = enum_.variant_list()?;
- let mut arms = vec![];
- for variant in list.variants() {
- let name = variant.name()?;
- let left = make::ext::ident_path("Self");
- let right = make::ext::ident_path(&format!("{}", name));
- let variant_name = make::path_pat(make::path_concat(left, right));
-
- let target = make::expr_path(make::ext::ident_path("f").into());
- let fmt_string = make::expr_literal(&(format!("\"{}\"", name))).into();
- let args = make::arg_list(vec![target, fmt_string]);
- let macro_name = make::expr_path(make::ext::ident_path("write"));
- let macro_call = make::expr_macro_call(macro_name, args);
-
- arms.push(make::match_arm(Some(variant_name.into()), None, macro_call.into()));
- }
-
- let match_target = make::expr_path(make::ext::ident_path("self"));
- let list = make::match_arm_list(arms).indent(ast::edit::IndentLevel(1));
- let match_expr = make::expr_match(match_target, list);
-
- let body = make::block_expr(None, Some(match_expr));
- let body = body.indent(ast::edit::IndentLevel(1));
- ted::replace(func.body()?.syntax(), body.clone_for_update().syntax());
- Some(())
- }
-
- ast::Adt::Struct(strukt) => {
- let name = format!("\"{}\"", annotated_name);
- let args = make::arg_list(Some(make::expr_literal(&name).into()));
- let target = make::expr_path(make::ext::ident_path("f"));
-
- let expr = match strukt.field_list() {
- // => f.debug_struct("Name").finish()
- None => make::expr_method_call(target, make::name_ref("debug_struct"), args),
-
- // => f.debug_struct("Name").field("foo", &self.foo).finish()
- Some(ast::FieldList::RecordFieldList(field_list)) => {
- let method = make::name_ref("debug_struct");
- let mut expr = make::expr_method_call(target, method, args);
- for field in field_list.fields() {
- let name = field.name()?;
- let f_name = make::expr_literal(&(format!("\"{}\"", name))).into();
- let f_path = make::expr_path(make::ext::ident_path("self"));
- let f_path = make::expr_ref(f_path, false);
- let f_path = make::expr_field(f_path, &format!("{}", name)).into();
- let args = make::arg_list(vec![f_name, f_path]);
- expr = make::expr_method_call(expr, make::name_ref("field"), args);
- }
- expr
- }
-
- // => f.debug_tuple("Name").field(self.0).finish()
- Some(ast::FieldList::TupleFieldList(field_list)) => {
- let method = make::name_ref("debug_tuple");
- let mut expr = make::expr_method_call(target, method, args);
- for (idx, _) in field_list.fields().enumerate() {
- let f_path = make::expr_path(make::ext::ident_path("self"));
- let f_path = make::expr_ref(f_path, false);
- let f_path = make::expr_field(f_path, &format!("{}", idx)).into();
- let method = make::name_ref("field");
- expr = make::expr_method_call(expr, method, make::arg_list(Some(f_path)));
- }
- expr
- }
- };
-
- let method = make::name_ref("finish");
- let expr = make::expr_method_call(expr, method, make::arg_list(None));
- let body = make::block_expr(None, Some(expr)).indent(ast::edit::IndentLevel(1));
- ted::replace(func.body()?.syntax(), body.clone_for_update().syntax());
- Some(())
- }
- }
-}
-
-/// Generate a `Debug` impl based on the fields and members of the target type.
-fn gen_default_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
- fn gen_default_call() -> ast::Expr {
- let trait_name = make::ext::ident_path("Default");
- let method_name = make::ext::ident_path("default");
- let fn_name = make::expr_path(make::path_concat(trait_name, method_name));
- make::expr_call(fn_name, make::arg_list(None))
- }
- match adt {
- // `Debug` cannot be derived for unions, so no default impl can be provided.
- ast::Adt::Union(_) => None,
- // Deriving `Debug` for enums is not stable yet.
- ast::Adt::Enum(_) => None,
- ast::Adt::Struct(strukt) => {
- let expr = match strukt.field_list() {
- Some(ast::FieldList::RecordFieldList(field_list)) => {
- let mut fields = vec![];
- for field in field_list.fields() {
- let method_call = gen_default_call();
- let name_ref = make::name_ref(&field.name()?.to_string());
- let field = make::record_expr_field(name_ref, Some(method_call));
- fields.push(field);
- }
- let struct_name = make::ext::ident_path("Self");
- let fields = make::record_expr_field_list(fields);
- make::record_expr(struct_name, fields).into()
- }
- Some(ast::FieldList::TupleFieldList(field_list)) => {
- let struct_name = make::expr_path(make::ext::ident_path("Self"));
- let fields = field_list.fields().map(|_| gen_default_call());
- make::expr_call(struct_name, make::arg_list(fields))
- }
- None => {
- let struct_name = make::ext::ident_path("Self");
- let fields = make::record_expr_field_list(None);
- make::record_expr(struct_name, fields).into()
- }
- };
- let body = make::block_expr(None, Some(expr)).indent(ast::edit::IndentLevel(1));
- ted::replace(func.body()?.syntax(), body.clone_for_update().syntax());
- Some(())
- }
- }
-}
fn update_attribute(
builder: &mut AssistBuilder,
input: &ast::TokenTree,
diff --git a/crates/ide_assists/src/utils.rs b/crates/ide_assists/src/utils.rs
index bcd7501724f..b4b9b6af80d 100644
--- a/crates/ide_assists/src/utils.rs
+++ b/crates/ide_assists/src/utils.rs
@@ -1,6 +1,7 @@
//! Assorted functions shared by several assists.
pub(crate) mod suggest_name;
+mod gen_trait_fn_body;
use std::ops;
@@ -25,6 +26,8 @@ use syntax::{
use crate::assist_context::{AssistBuilder, AssistContext};
+pub(crate) use gen_trait_fn_body::gen_trait_fn_body;
+
pub(crate) fn unwrap_trivial_block(block: ast::BlockExpr) -> ast::Expr {
extract_trivial_expression(&block)
.filter(|expr| !expr.syntax().text().contains_char('\n'))
diff --git a/crates/ide_assists/src/utils/gen_trait_fn_body.rs b/crates/ide_assists/src/utils/gen_trait_fn_body.rs
new file mode 100644
index 00000000000..17e006a7553
--- /dev/null
+++ b/crates/ide_assists/src/utils/gen_trait_fn_body.rs
@@ -0,0 +1,153 @@
+//! This module contains functions to generate default trait impl function bodies where possible.
+
+use syntax::{
+ ast::{self, edit::AstNodeEdit, make, AstNode, NameOwner},
+ ted,
+};
+
+/// Generate custom trait bodies where possible.
+///
+/// Returns `Option` so that we can use `?` rather than `if let Some`. Returning
+/// `None` means that generating a custom trait body failed, and the body will remain
+/// as `todo!` instead.
+pub(crate) fn gen_trait_fn_body(
+ func: &ast::Fn,
+ trait_path: &ast::Path,
+ adt: &ast::Adt,
+) -> Option<()> {
+ match trait_path.segment()?.name_ref()?.text().as_str() {
+ "Debug" => gen_debug_impl(adt, func),
+ "Default" => gen_default_impl(adt, func),
+ _ => None,
+ }
+}
+
+/// Generate a `Debug` impl based on the fields and members of the target type.
+fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
+ let annotated_name = adt.name()?;
+ match adt {
+ // `Debug` cannot be derived for unions, so no default impl can be provided.
+ ast::Adt::Union(_) => None,
+
+ // => match self { Self::Variant => write!(f, "Variant") }
+ ast::Adt::Enum(enum_) => {
+ let list = enum_.variant_list()?;
+ let mut arms = vec![];
+ for variant in list.variants() {
+ let name = variant.name()?;
+ let left = make::ext::ident_path("Self");
+ let right = make::ext::ident_path(&format!("{}", name));
+ let variant_name = make::path_pat(make::path_concat(left, right));
+
+ let target = make::expr_path(make::ext::ident_path("f").into());
+ let fmt_string = make::expr_literal(&(format!("\"{}\"", name))).into();
+ let args = make::arg_list(vec![target, fmt_string]);
+ let macro_name = make::expr_path(make::ext::ident_path("write"));
+ let macro_call = make::expr_macro_call(macro_name, args);
+
+ arms.push(make::match_arm(Some(variant_name.into()), None, macro_call.into()));
+ }
+
+ let match_target = make::expr_path(make::ext::ident_path("self"));
+ let list = make::match_arm_list(arms).indent(ast::edit::IndentLevel(1));
+ let match_expr = make::expr_match(match_target, list);
+
+ let body = make::block_expr(None, Some(match_expr));
+ let body = body.indent(ast::edit::IndentLevel(1));
+ ted::replace(func.body()?.syntax(), body.clone_for_update().syntax());
+ Some(())
+ }
+
+ ast::Adt::Struct(strukt) => {
+ let name = format!("\"{}\"", annotated_name);
+ let args = make::arg_list(Some(make::expr_literal(&name).into()));
+ let target = make::expr_path(make::ext::ident_path("f"));
+
+ let expr = match strukt.field_list() {
+ // => f.debug_struct("Name").finish()
+ None => make::expr_method_call(target, make::name_ref("debug_struct"), args),
+
+ // => f.debug_struct("Name").field("foo", &self.foo).finish()
+ Some(ast::FieldList::RecordFieldList(field_list)) => {
+ let method = make::name_ref("debug_struct");
+ let mut expr = make::expr_method_call(target, method, args);
+ for field in field_list.fields() {
+ let name = field.name()?;
+ let f_name = make::expr_literal(&(format!("\"{}\"", name))).into();
+ let f_path = make::expr_path(make::ext::ident_path("self"));
+ let f_path = make::expr_ref(f_path, false);
+ let f_path = make::expr_field(f_path, &format!("{}", name)).into();
+ let args = make::arg_list(vec![f_name, f_path]);
+ expr = make::expr_method_call(expr, make::name_ref("field"), args);
+ }
+ expr
+ }
+
+ // => f.debug_tuple("Name").field(self.0).finish()
+ Some(ast::FieldList::TupleFieldList(field_list)) => {
+ let method = make::name_ref("debug_tuple");
+ let mut expr = make::expr_method_call(target, method, args);
+ for (idx, _) in field_list.fields().enumerate() {
+ let f_path = make::expr_path(make::ext::ident_path("self"));
+ let f_path = make::expr_ref(f_path, false);
+ let f_path = make::expr_field(f_path, &format!("{}", idx)).into();
+ let method = make::name_ref("field");
+ expr = make::expr_method_call(expr, method, make::arg_list(Some(f_path)));
+ }
+ expr
+ }
+ };
+
+ let method = make::name_ref("finish");
+ let expr = make::expr_method_call(expr, method, make::arg_list(None));
+ let body = make::block_expr(None, Some(expr)).indent(ast::edit::IndentLevel(1));
+ ted::replace(func.body()?.syntax(), body.clone_for_update().syntax());
+ Some(())
+ }
+ }
+}
+
+/// Generate a `Debug` impl based on the fields and members of the target type.
+fn gen_default_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
+ fn gen_default_call() -> ast::Expr {
+ let trait_name = make::ext::ident_path("Default");
+ let method_name = make::ext::ident_path("default");
+ let fn_name = make::expr_path(make::path_concat(trait_name, method_name));
+ make::expr_call(fn_name, make::arg_list(None))
+ }
+ match adt {
+ // `Debug` cannot be derived for unions, so no default impl can be provided.
+ ast::Adt::Union(_) => None,
+ // Deriving `Debug` for enums is not stable yet.
+ ast::Adt::Enum(_) => None,
+ ast::Adt::Struct(strukt) => {
+ let expr = match strukt.field_list() {
+ Some(ast::FieldList::RecordFieldList(field_list)) => {
+ let mut fields = vec![];
+ for field in field_list.fields() {
+ let method_call = gen_default_call();
+ let name_ref = make::name_ref(&field.name()?.to_string());
+ let field = make::record_expr_field(name_ref, Some(method_call));
+ fields.push(field);
+ }
+ let struct_name = make::ext::ident_path("Self");
+ let fields = make::record_expr_field_list(fields);
+ make::record_expr(struct_name, fields).into()
+ }
+ Some(ast::FieldList::TupleFieldList(field_list)) => {
+ let struct_name = make::expr_path(make::ext::ident_path("Self"));
+ let fields = field_list.fields().map(|_| gen_default_call());
+ make::expr_call(struct_name, make::arg_list(fields))
+ }
+ None => {
+ let struct_name = make::ext::ident_path("Self");
+ let fields = make::record_expr_field_list(None);
+ make::record_expr(struct_name, fields).into()
+ }
+ };
+ let body = make::block_expr(None, Some(expr)).indent(ast::edit::IndentLevel(1));
+ ted::replace(func.body()?.syntax(), body.clone_for_update().syntax());
+ Some(())
+ }
+ }
+}
diff --git a/crates/rust-analyzer/tests/slow-tests/tidy.rs b/crates/rust-analyzer/tests/slow-tests/tidy.rs
index 4c3ff31533f..4e99ae67d85 100644
--- a/crates/rust-analyzer/tests/slow-tests/tidy.rs
+++ b/crates/rust-analyzer/tests/slow-tests/tidy.rs
@@ -280,6 +280,7 @@ fn check_todo(path: &Path, text: &str) {
"ast/make.rs",
// The documentation in string literals may contain anything for its own purposes
"ide_db/src/helpers/generated_lints.rs",
+ "ide_assists/src/utils/gen_trait_fn_body.rs",
"ide_assists/src/tests/generated.rs",
];
if need_todo.iter().any(|p| path.ends_with(p)) {