use hir::HasSource;
use ide_db::{
    syntax_helpers::insert_whitespace_into_node::insert_ws_into, traits::resolve_target_trait,
};
use syntax::ast::{self, make, AstNode};

use crate::{
    assist_context::{AssistContext, Assists},
    utils::{
        add_trait_assoc_items_to_impl, filter_assoc_items, gen_trait_fn_body, render_snippet,
        Cursor, DefaultMethods,
    },
    AssistId, AssistKind,
};

// Assist: add_impl_missing_members
//
// Adds scaffold for required impl members.
//
// ```
// trait Trait<T> {
//     type X;
//     fn foo(&self) -> T;
//     fn bar(&self) {}
// }
//
// impl Trait<u32> for () {$0
//
// }
// ```
// ->
// ```
// trait Trait<T> {
//     type X;
//     fn foo(&self) -> T;
//     fn bar(&self) {}
// }
//
// impl Trait<u32> for () {
//     $0type X;
//
//     fn foo(&self) -> u32 {
//         todo!()
//     }
// }
// ```
pub(crate) fn add_missing_impl_members(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
    add_missing_impl_members_inner(
        acc,
        ctx,
        DefaultMethods::No,
        "add_impl_missing_members",
        "Implement missing members",
    )
}

// Assist: add_impl_default_members
//
// Adds scaffold for overriding default impl members.
//
// ```
// trait Trait {
//     type X;
//     fn foo(&self);
//     fn bar(&self) {}
// }
//
// impl Trait for () {
//     type X = ();
//     fn foo(&self) {}$0
// }
// ```
// ->
// ```
// trait Trait {
//     type X;
//     fn foo(&self);
//     fn bar(&self) {}
// }
//
// impl Trait for () {
//     type X = ();
//     fn foo(&self) {}
//
//     $0fn bar(&self) {}
// }
// ```
pub(crate) fn add_missing_default_members(
    acc: &mut Assists,
    ctx: &AssistContext<'_>,
) -> Option<()> {
    add_missing_impl_members_inner(
        acc,
        ctx,
        DefaultMethods::Only,
        "add_impl_default_members",
        "Implement default members",
    )
}

fn add_missing_impl_members_inner(
    acc: &mut Assists,
    ctx: &AssistContext<'_>,
    mode: DefaultMethods,
    assist_id: &'static str,
    label: &'static str,
) -> Option<()> {
    let _p = profile::span("add_missing_impl_members_inner");
    let impl_def = ctx.find_node_at_offset::<ast::Impl>()?;

    if ctx.token_at_offset().all(|t| {
        t.parent_ancestors()
            .any(|s| ast::BlockExpr::can_cast(s.kind()) || ast::ParamList::can_cast(s.kind()))
    }) {
        return None;
    }

    let target_scope = ctx.sema.scope(impl_def.syntax())?;
    let trait_ = resolve_target_trait(&ctx.sema, &impl_def)?;

    let missing_items = filter_assoc_items(
        &ctx.sema,
        &ide_db::traits::get_missing_assoc_items(&ctx.sema, &impl_def),
        mode,
    );

    if missing_items.is_empty() {
        return None;
    }

    let target = impl_def.syntax().text_range();
    acc.add(AssistId(assist_id, AssistKind::QuickFix), label, target, |builder| {
        let missing_items = missing_items
            .into_iter()
            .map(|it| {
                if ctx.sema.hir_file_for(it.syntax()).is_macro() {
                    if let Some(it) = ast::AssocItem::cast(insert_ws_into(it.syntax().clone())) {
                        return it;
                    }
                }
                it.clone_for_update()
            })
            .collect();
        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 DefaultMethods::No = mode {
                    if let ast::AssocItem::Fn(func) = &first_new_item {
                        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());
                                }
                            }
                        }
                    }
                }
                builder.replace_snippet(
                    cap,
                    target,
                    render_snippet(cap, new_impl_def.syntax(), cursor),
                )
            }
        };
    })
}

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};

    use super::*;

    #[test]
    fn test_add_missing_impl_members() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo {
    type Output;

    const CONST: usize = 42;
    const CONST_2: i32;

    fn foo(&self);
    fn bar(&self);
    fn baz(&self);
}

struct S;

impl Foo for S {
    fn bar(&self) {}
$0
}"#,
            r#"
trait Foo {
    type Output;

    const CONST: usize = 42;
    const CONST_2: i32;

    fn foo(&self);
    fn bar(&self);
    fn baz(&self);
}

struct S;

impl Foo for S {
    fn bar(&self) {}

    $0type Output;

    const CONST_2: i32;

    fn foo(&self) {
        todo!()
    }

    fn baz(&self) {
        todo!()
    }

}"#,
        );
    }

    #[test]
    fn test_copied_overriden_members() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo {
    fn foo(&self);
    fn bar(&self) -> bool { true }
    fn baz(&self) -> u32 { 42 }
}

struct S;

impl Foo for S {
    fn bar(&self) {}
$0
}"#,
            r#"
trait Foo {
    fn foo(&self);
    fn bar(&self) -> bool { true }
    fn baz(&self) -> u32 { 42 }
}

struct S;

impl Foo for S {
    fn bar(&self) {}

    fn foo(&self) {
        ${0:todo!()}
    }

}"#,
        );
    }

    #[test]
    fn test_empty_impl_def() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo { fn foo(&self); }
struct S;
impl Foo for S { $0 }"#,
            r#"
trait Foo { fn foo(&self); }
struct S;
impl Foo for S {
    fn foo(&self) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_impl_def_without_braces() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo { fn foo(&self); }
struct S;
impl Foo for S$0"#,
            r#"
trait Foo { fn foo(&self); }
struct S;
impl Foo for S {
    fn foo(&self) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn fill_in_type_params_1() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo<T> { fn foo(&self, t: T) -> &T; }
struct S;
impl Foo<u32> for S { $0 }"#,
            r#"
trait Foo<T> { fn foo(&self, t: T) -> &T; }
struct S;
impl Foo<u32> for S {
    fn foo(&self, t: u32) -> &u32 {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn fill_in_type_params_2() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo<T> { fn foo(&self, t: T) -> &T; }
struct S;
impl<U> Foo<U> for S { $0 }"#,
            r#"
trait Foo<T> { fn foo(&self, t: T) -> &T; }
struct S;
impl<U> Foo<U> for S {
    fn foo(&self, t: U) -> &U {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_cursor_after_empty_impl_def() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo { fn foo(&self); }
struct S;
impl Foo for S {}$0"#,
            r#"
trait Foo { fn foo(&self); }
struct S;
impl Foo for S {
    fn foo(&self) {
        ${0:todo!()}
    }
}"#,
        )
    }

    #[test]
    fn test_qualify_path_1() {
        check_assist(
            add_missing_impl_members,
            r#"
mod foo {
    pub struct Bar;
    pub trait Foo { fn foo(&self, bar: Bar); }
}
struct S;
impl foo::Foo for S { $0 }"#,
            r#"
mod foo {
    pub struct Bar;
    pub trait Foo { fn foo(&self, bar: Bar); }
}
struct S;
impl foo::Foo for S {
    fn foo(&self, bar: foo::Bar) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_qualify_path_2() {
        check_assist(
            add_missing_impl_members,
            r#"
mod foo {
    pub mod bar {
        pub struct Bar;
        pub trait Foo { fn foo(&self, bar: Bar); }
    }
}

use foo::bar;

struct S;
impl bar::Foo for S { $0 }"#,
            r#"
mod foo {
    pub mod bar {
        pub struct Bar;
        pub trait Foo { fn foo(&self, bar: Bar); }
    }
}

use foo::bar;

struct S;
impl bar::Foo for S {
    fn foo(&self, bar: bar::Bar) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_qualify_path_generic() {
        check_assist(
            add_missing_impl_members,
            r#"
mod foo {
    pub struct Bar<T>;
    pub trait Foo { fn foo(&self, bar: Bar<u32>); }
}
struct S;
impl foo::Foo for S { $0 }"#,
            r#"
mod foo {
    pub struct Bar<T>;
    pub trait Foo { fn foo(&self, bar: Bar<u32>); }
}
struct S;
impl foo::Foo for S {
    fn foo(&self, bar: foo::Bar<u32>) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_qualify_path_and_substitute_param() {
        check_assist(
            add_missing_impl_members,
            r#"
mod foo {
    pub struct Bar<T>;
    pub trait Foo<T> { fn foo(&self, bar: Bar<T>); }
}
struct S;
impl foo::Foo<u32> for S { $0 }"#,
            r#"
mod foo {
    pub struct Bar<T>;
    pub trait Foo<T> { fn foo(&self, bar: Bar<T>); }
}
struct S;
impl foo::Foo<u32> for S {
    fn foo(&self, bar: foo::Bar<u32>) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_substitute_param_no_qualify() {
        // when substituting params, the substituted param should not be qualified!
        check_assist(
            add_missing_impl_members,
            r#"
mod foo {
    pub trait Foo<T> { fn foo(&self, bar: T); }
    pub struct Param;
}
struct Param;
struct S;
impl foo::Foo<Param> for S { $0 }"#,
            r#"
mod foo {
    pub trait Foo<T> { fn foo(&self, bar: T); }
    pub struct Param;
}
struct Param;
struct S;
impl foo::Foo<Param> for S {
    fn foo(&self, bar: Param) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_qualify_path_associated_item() {
        check_assist(
            add_missing_impl_members,
            r#"
mod foo {
    pub struct Bar<T>;
    impl Bar<T> { type Assoc = u32; }
    pub trait Foo { fn foo(&self, bar: Bar<u32>::Assoc); }
}
struct S;
impl foo::Foo for S { $0 }"#,
            r#"
mod foo {
    pub struct Bar<T>;
    impl Bar<T> { type Assoc = u32; }
    pub trait Foo { fn foo(&self, bar: Bar<u32>::Assoc); }
}
struct S;
impl foo::Foo for S {
    fn foo(&self, bar: foo::Bar<u32>::Assoc) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_qualify_path_nested() {
        check_assist(
            add_missing_impl_members,
            r#"
mod foo {
    pub struct Bar<T>;
    pub struct Baz;
    pub trait Foo { fn foo(&self, bar: Bar<Baz>); }
}
struct S;
impl foo::Foo for S { $0 }"#,
            r#"
mod foo {
    pub struct Bar<T>;
    pub struct Baz;
    pub trait Foo { fn foo(&self, bar: Bar<Baz>); }
}
struct S;
impl foo::Foo for S {
    fn foo(&self, bar: foo::Bar<foo::Baz>) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_qualify_path_fn_trait_notation() {
        check_assist(
            add_missing_impl_members,
            r#"
mod foo {
    pub trait Fn<Args> { type Output; }
    pub trait Foo { fn foo(&self, bar: dyn Fn(u32) -> i32); }
}
struct S;
impl foo::Foo for S { $0 }"#,
            r#"
mod foo {
    pub trait Fn<Args> { type Output; }
    pub trait Foo { fn foo(&self, bar: dyn Fn(u32) -> i32); }
}
struct S;
impl foo::Foo for S {
    fn foo(&self, bar: dyn Fn(u32) -> i32) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_empty_trait() {
        check_assist_not_applicable(
            add_missing_impl_members,
            r#"
trait Foo;
struct S;
impl Foo for S { $0 }"#,
        )
    }

    #[test]
    fn test_ignore_unnamed_trait_members_and_default_methods() {
        check_assist_not_applicable(
            add_missing_impl_members,
            r#"
trait Foo {
    fn (arg: u32);
    fn valid(some: u32) -> bool { false }
}
struct S;
impl Foo for S { $0 }"#,
        )
    }

    #[test]
    fn test_with_docstring_and_attrs() {
        check_assist(
            add_missing_impl_members,
            r#"
#[doc(alias = "test alias")]
trait Foo {
    /// doc string
    type Output;

    #[must_use]
    fn foo(&self);
}
struct S;
impl Foo for S {}$0"#,
            r#"
#[doc(alias = "test alias")]
trait Foo {
    /// doc string
    type Output;

    #[must_use]
    fn foo(&self);
}
struct S;
impl Foo for S {
    $0type Output;

    fn foo(&self) {
        todo!()
    }
}"#,
        )
    }

    #[test]
    fn test_default_methods() {
        check_assist(
            add_missing_default_members,
            r#"
trait Foo {
    type Output;

    const CONST: usize = 42;
    const CONST_2: i32;

    fn valid(some: u32) -> bool { false }
    fn foo(some: u32) -> bool;
}
struct S;
impl Foo for S { $0 }"#,
            r#"
trait Foo {
    type Output;

    const CONST: usize = 42;
    const CONST_2: i32;

    fn valid(some: u32) -> bool { false }
    fn foo(some: u32) -> bool;
}
struct S;
impl Foo for S {
    $0const CONST: usize = 42;

    fn valid(some: u32) -> bool { false }
}"#,
        )
    }

    #[test]
    fn test_generic_single_default_parameter() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo<T = Self> {
    fn bar(&self, other: &T);
}

struct S;
impl Foo for S { $0 }"#,
            r#"
trait Foo<T = Self> {
    fn bar(&self, other: &T);
}

struct S;
impl Foo for S {
    fn bar(&self, other: &Self) {
        ${0:todo!()}
    }
}"#,
        )
    }

    #[test]
    fn test_generic_default_parameter_is_second() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo<T1, T2 = Self> {
    fn bar(&self, this: &T1, that: &T2);
}

struct S<T>;
impl Foo<T> for S<T> { $0 }"#,
            r#"
trait Foo<T1, T2 = Self> {
    fn bar(&self, this: &T1, that: &T2);
}

struct S<T>;
impl Foo<T> for S<T> {
    fn bar(&self, this: &T, that: &Self) {
        ${0:todo!()}
    }
}"#,
        )
    }

    #[test]
    fn test_assoc_type_bounds_are_removed() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Tr {
    type Ty: Copy + 'static;
}

impl Tr for ()$0 {
}"#,
            r#"
trait Tr {
    type Ty: Copy + 'static;
}

impl Tr for () {
    $0type Ty;
}"#,
        )
    }

    #[test]
    fn test_whitespace_fixup_preserves_bad_tokens() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Tr {
    fn foo();
}

impl Tr for ()$0 {
    +++
}"#,
            r#"
trait Tr {
    fn foo();
}

impl Tr for () {
    fn foo() {
        ${0:todo!()}
    }
    +++
}"#,
        )
    }

    #[test]
    fn test_whitespace_fixup_preserves_comments() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Tr {
    fn foo();
}

impl Tr for ()$0 {
    // very important
}"#,
            r#"
trait Tr {
    fn foo();
}

impl Tr for () {
    fn foo() {
        ${0:todo!()}
    }
    // very important
}"#,
        )
    }

    #[test]
    fn weird_path() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Test {
    fn foo(&self, x: crate)
}
impl Test for () {
    $0
}
"#,
            r#"
trait Test {
    fn foo(&self, x: crate)
}
impl Test for () {
    fn foo(&self, x: crate) {
        ${0:todo!()}
    }
}
"#,
        )
    }

    #[test]
    fn missing_generic_type() {
        check_assist(
            add_missing_impl_members,
            r#"
trait Foo<BAR> {
    fn foo(&self, bar: BAR);
}
impl Foo for () {
    $0
}
"#,
            r#"
trait Foo<BAR> {
    fn foo(&self, bar: BAR);
}
impl Foo for () {
    fn foo(&self, bar: BAR) {
        ${0:todo!()}
    }
}
"#,
        )
    }

    #[test]
    fn does_not_requalify_self_as_crate() {
        check_assist(
            add_missing_default_members,
            r"
struct Wrapper<T>(T);

trait T {
    fn f(self) -> Wrapper<Self> {
        Wrapper(self)
    }
}

impl T for () {
    $0
}
",
            r"
struct Wrapper<T>(T);

trait T {
    fn f(self) -> Wrapper<Self> {
        Wrapper(self)
    }
}

impl T for () {
    $0fn f(self) -> Wrapper<Self> {
        Wrapper(self)
    }
}
",
        );
    }

    #[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())
    }
}
"#,
        )
    }

    #[test]
    fn test_from_macro() {
        check_assist(
            add_missing_default_members,
            r#"
macro_rules! foo {
    () => {
        trait FooB {
            fn foo<'lt>(&'lt self) {}
        }
    }
}
foo!();
struct Foo(usize);

impl FooB for Foo {
    $0
}
"#,
            r#"
macro_rules! foo {
    () => {
        trait FooB {
            fn foo<'lt>(&'lt self) {}
        }
    }
}
foo!();
struct Foo(usize);

impl FooB for Foo {
    $0fn foo<'lt>(&'lt self){}
}
"#,
        )
    }

    #[test]
    fn test_assoc_type_when_trait_with_same_name_in_scope() {
        check_assist(
            add_missing_impl_members,
            r#"
pub trait Foo {}

pub trait Types {
    type Foo;
}

pub trait Behavior<T: Types> {
    fn reproduce(&self, foo: T::Foo);
}

pub struct Impl;

impl<T: Types> Behavior<T> for Impl { $0 }"#,
            r#"
pub trait Foo {}

pub trait Types {
    type Foo;
}

pub trait Behavior<T: Types> {
    fn reproduce(&self, foo: T::Foo);
}

pub struct Impl;

impl<T: Types> Behavior<T> for Impl {
    fn reproduce(&self, foo: <T as Types>::Foo) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_assoc_type_on_concrete_type() {
        check_assist(
            add_missing_impl_members,
            r#"
pub trait Types {
    type Foo;
}

impl Types for u32 {
    type Foo = bool;
}

pub trait Behavior<T: Types> {
    fn reproduce(&self, foo: T::Foo);
}

pub struct Impl;

impl Behavior<u32> for Impl { $0 }"#,
            r#"
pub trait Types {
    type Foo;
}

impl Types for u32 {
    type Foo = bool;
}

pub trait Behavior<T: Types> {
    fn reproduce(&self, foo: T::Foo);
}

pub struct Impl;

impl Behavior<u32> for Impl {
    fn reproduce(&self, foo: <u32 as Types>::Foo) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_assoc_type_on_concrete_type_qualified() {
        check_assist(
            add_missing_impl_members,
            r#"
pub trait Types {
    type Foo;
}

impl Types for std::string::String {
    type Foo = bool;
}

pub trait Behavior<T: Types> {
    fn reproduce(&self, foo: T::Foo);
}

pub struct Impl;

impl Behavior<std::string::String> for Impl { $0 }"#,
            r#"
pub trait Types {
    type Foo;
}

impl Types for std::string::String {
    type Foo = bool;
}

pub trait Behavior<T: Types> {
    fn reproduce(&self, foo: T::Foo);
}

pub struct Impl;

impl Behavior<std::string::String> for Impl {
    fn reproduce(&self, foo: <std::string::String as Types>::Foo) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_assoc_type_on_concrete_type_multi_option_ambiguous() {
        check_assist(
            add_missing_impl_members,
            r#"
pub trait Types {
    type Foo;
}

pub trait Types2 {
    type Foo;
}

impl Types for u32 {
    type Foo = bool;
}

impl Types2 for u32 {
    type Foo = String;
}

pub trait Behavior<T: Types + Types2> {
    fn reproduce(&self, foo: <T as Types2>::Foo);
}

pub struct Impl;

impl Behavior<u32> for Impl { $0 }"#,
            r#"
pub trait Types {
    type Foo;
}

pub trait Types2 {
    type Foo;
}

impl Types for u32 {
    type Foo = bool;
}

impl Types2 for u32 {
    type Foo = String;
}

pub trait Behavior<T: Types + Types2> {
    fn reproduce(&self, foo: <T as Types2>::Foo);
}

pub struct Impl;

impl Behavior<u32> for Impl {
    fn reproduce(&self, foo: <u32 as Types2>::Foo) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_assoc_type_on_concrete_type_multi_option() {
        check_assist(
            add_missing_impl_members,
            r#"
pub trait Types {
    type Foo;
}

pub trait Types2 {
    type Bar;
}

impl Types for u32 {
    type Foo = bool;
}

impl Types2 for u32 {
    type Bar = String;
}

pub trait Behavior<T: Types + Types2> {
    fn reproduce(&self, foo: T::Bar);
}

pub struct Impl;

impl Behavior<u32> for Impl { $0 }"#,
            r#"
pub trait Types {
    type Foo;
}

pub trait Types2 {
    type Bar;
}

impl Types for u32 {
    type Foo = bool;
}

impl Types2 for u32 {
    type Bar = String;
}

pub trait Behavior<T: Types + Types2> {
    fn reproduce(&self, foo: T::Bar);
}

pub struct Impl;

impl Behavior<u32> for Impl {
    fn reproduce(&self, foo: <u32 as Types2>::Bar) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_assoc_type_on_concrete_type_multi_option_foreign() {
        check_assist(
            add_missing_impl_members,
            r#"
mod bar {
    pub trait Types2 {
        type Bar;
    }
}

pub trait Types {
    type Foo;
}

impl Types for u32 {
    type Foo = bool;
}

impl bar::Types2 for u32 {
    type Bar = String;
}

pub trait Behavior<T: Types + bar::Types2> {
    fn reproduce(&self, foo: T::Bar);
}

pub struct Impl;

impl Behavior<u32> for Impl { $0 }"#,
            r#"
mod bar {
    pub trait Types2 {
        type Bar;
    }
}

pub trait Types {
    type Foo;
}

impl Types for u32 {
    type Foo = bool;
}

impl bar::Types2 for u32 {
    type Bar = String;
}

pub trait Behavior<T: Types + bar::Types2> {
    fn reproduce(&self, foo: T::Bar);
}

pub struct Impl;

impl Behavior<u32> for Impl {
    fn reproduce(&self, foo: <u32 as bar::Types2>::Bar) {
        ${0:todo!()}
    }
}"#,
        );
    }

    #[test]
    fn test_transform_path_in_path_expr() {
        check_assist(
            add_missing_default_members,
            r#"
pub trait Const {
    const FOO: u32;
}

pub trait Trait<T: Const> {
    fn foo() -> bool {
        match T::FOO {
            0 => true,
            _ => false,
        }
    }
}

impl Const for u32 {
    const FOO: u32 = 1;
}

struct Impl;

impl Trait<u32> for Impl { $0 }"#,
            r#"
pub trait Const {
    const FOO: u32;
}

pub trait Trait<T: Const> {
    fn foo() -> bool {
        match T::FOO {
            0 => true,
            _ => false,
        }
    }
}

impl Const for u32 {
    const FOO: u32 = 1;
}

struct Impl;

impl Trait<u32> for Impl {
    $0fn foo() -> bool {
        match <u32 as Const>::FOO {
            0 => true,
            _ => false,
        }
    }
}"#,
        );
    }

    #[test]
    fn test_default_partial_eq() {
        check_assist(
            add_missing_default_members,
            r#"
//- minicore: eq
struct SomeStruct {
    data: usize,
    field: (usize, usize),
}
impl PartialEq for SomeStruct {$0}
"#,
            r#"
struct SomeStruct {
    data: usize,
    field: (usize, usize),
}
impl PartialEq for SomeStruct {
    $0fn ne(&self, other: &Self) -> bool {
            !self.eq(other)
        }
}
"#,
        );
    }

    #[test]
    fn test_ignore_function_body() {
        check_assist_not_applicable(
            add_missing_default_members,
            r#"
trait Trait {
    type X;
    fn foo(&self);
    fn bar(&self) {}
}

impl Trait for () {
    type X = u8;
    fn foo(&self) {$0
        let x = 5;
    }
}"#,
        )
    }

    #[test]
    fn test_ignore_param_list() {
        check_assist_not_applicable(
            add_missing_impl_members,
            r#"
trait Trait {
    type X;
    fn foo(&self);
    fn bar(&self);
}

impl Trait for () {
    type X = u8;
    fn foo(&self$0) {
        let x = 5;
    }
}"#,
        )
    }

    #[test]
    fn test_ignore_scope_inside_function() {
        check_assist_not_applicable(
            add_missing_impl_members,
            r#"
trait Trait {
    type X;
    fn foo(&self);
    fn bar(&self);
}

impl Trait for () {
    type X = u8;
    fn foo(&self) {
        let x = async {$0 5 };
    }
}"#,
        )
    }

    #[test]
    fn test_apply_outside_function() {
        check_assist(
            add_missing_default_members,
            r#"
trait Trait {
    type X;
    fn foo(&self);
    fn bar(&self) {}
}

impl Trait for () {
    type X = u8;
    fn foo(&self)$0 {}
}"#,
            r#"
trait Trait {
    type X;
    fn foo(&self);
    fn bar(&self) {}
}

impl Trait for () {
    type X = u8;
    fn foo(&self) {}

    $0fn bar(&self) {}
}"#,
        )
    }
}