rust/crates/ide_assists/src/handlers/inline_call.rs
2021-10-13 14:39:37 +02:00

1080 lines
24 KiB
Rust

use ast::make;
use either::Either;
use hir::{db::HirDatabase, PathResolution, Semantics, TypeInfo};
use ide_db::{
base_db::{FileId, FileRange},
defs::Definition,
helpers::{insert_use::remove_path_if_in_use_stmt, node_ext::expr_as_name_ref},
path_transform::PathTransform,
search::{FileReference, SearchScope},
RootDatabase,
};
use itertools::{izip, Itertools};
use syntax::{
ast::{self, edit_in_place::Indent, HasArgList, PathExpr},
ted, AstNode,
};
use crate::{
assist_context::{AssistContext, Assists},
AssistId, AssistKind,
};
// Assist: inline_into_callers
//
// Inline a function or method body into all of its callers where possible, creating a `let` statement per parameter
// unless the parameter can be inlined. The parameter will be inlined either if it the supplied argument is a simple local
// or if the parameter is only accessed inside the function body once.
// If all calls can be inlined the function will be removed.
//
// ```
// fn print(_: &str) {}
// fn foo$0(word: &str) {
// if !word.is_empty() {
// print(word);
// }
// }
// fn bar() {
// foo("안녕하세요");
// foo("여러분");
// }
// ```
// ->
// ```
// fn print(_: &str) {}
//
// fn bar() {
// {
// let word = "안녕하세요";
// if !word.is_empty() {
// print(word);
// }
// };
// {
// let word = "여러분";
// if !word.is_empty() {
// print(word);
// }
// };
// }
// ```
pub(crate) fn inline_into_callers(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
let def_file = ctx.file_id();
let name = ctx.find_node_at_offset::<ast::Name>()?;
let ast_func = name.syntax().parent().and_then(ast::Fn::cast)?;
let func_body = ast_func.body()?;
let param_list = ast_func.param_list()?;
let function = ctx.sema.to_def(&ast_func)?;
let params = get_fn_params(ctx.sema.db, function, &param_list)?;
let usages = Definition::ModuleDef(hir::ModuleDef::Function(function)).usages(&ctx.sema);
if !usages.at_least_one() {
return None;
}
let is_recursive_fn = usages
.clone()
.in_scope(SearchScope::file_range(FileRange {
file_id: def_file,
range: func_body.syntax().text_range(),
}))
.at_least_one();
if is_recursive_fn {
cov_mark::hit!(inline_into_callers_recursive);
return None;
}
acc.add(
AssistId("inline_into_callers", AssistKind::RefactorInline),
"Inline into all callers",
name.syntax().text_range(),
|builder| {
let mut usages = usages.all();
let current_file_usage = usages.references.remove(&def_file);
let mut remove_def = true;
let mut inline_refs_for_file = |file_id, refs: Vec<FileReference>| {
builder.edit_file(file_id);
let count = refs.len();
// The collects are required as we are otherwise iterating while mutating 🙅‍♀️🙅‍♂️
let (name_refs, name_refs_use): (Vec<_>, Vec<_>) = refs
.into_iter()
.filter_map(|file_ref| match file_ref.name {
ast::NameLike::NameRef(name_ref) => Some(name_ref),
_ => None,
})
.partition_map(|name_ref| {
match name_ref.syntax().ancestors().find_map(ast::UseTree::cast) {
Some(use_tree) => Either::Right(builder.make_mut(use_tree)),
None => Either::Left(name_ref),
}
});
let call_infos: Vec<_> = name_refs
.into_iter()
.filter_map(CallInfo::from_name_ref)
.map(|call_info| {
let mut_node = builder.make_syntax_mut(call_info.node.syntax().clone());
(call_info, mut_node)
})
.collect();
let replaced = call_infos
.into_iter()
.map(|(call_info, mut_node)| {
let replacement =
inline(&ctx.sema, def_file, function, &func_body, &params, &call_info);
ted::replace(mut_node, replacement.syntax());
})
.count();
if replaced + name_refs_use.len() == count {
// we replaced all usages in this file, so we can remove the imports
name_refs_use.into_iter().for_each(|use_tree| {
if let Some(path) = use_tree.path() {
remove_path_if_in_use_stmt(&path);
}
})
} else {
remove_def = false;
}
};
for (file_id, refs) in usages.into_iter() {
inline_refs_for_file(file_id, refs);
}
match current_file_usage {
Some(refs) => inline_refs_for_file(def_file, refs),
None => builder.edit_file(def_file),
}
if remove_def {
builder.delete(ast_func.syntax().text_range());
}
},
)
}
// Assist: inline_call
//
// Inlines a function or method body creating a `let` statement per parameter unless the parameter
// can be inlined. The parameter will be inlined either if it the supplied argument is a simple local
// or if the parameter is only accessed inside the function body once.
//
// ```
// # //- minicore: option
// fn foo(name: Option<&str>) {
// let name = name.unwrap$0();
// }
// ```
// ->
// ```
// fn foo(name: Option<&str>) {
// let name = match name {
// Some(val) => val,
// None => panic!("called `Option::unwrap()` on a `None` value"),
// };
// }
// ```
pub(crate) fn inline_call(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
let name_ref: ast::NameRef = ctx.find_node_at_offset()?;
let call_info = CallInfo::from_name_ref(name_ref.clone())?;
let (function, label) = match &call_info.node {
ast::CallableExpr::Call(call) => {
let path = match call.expr()? {
ast::Expr::PathExpr(path) => path.path(),
_ => None,
}?;
let function = match ctx.sema.resolve_path(&path)? {
PathResolution::Def(hir::ModuleDef::Function(f)) => f,
PathResolution::AssocItem(hir::AssocItem::Function(f)) => f,
_ => return None,
};
(function, format!("Inline `{}`", path))
}
ast::CallableExpr::MethodCall(call) => {
(ctx.sema.resolve_method_call(call)?, format!("Inline `{}`", name_ref))
}
};
let fn_source = ctx.sema.source(function)?;
let fn_body = fn_source.value.body()?;
let param_list = fn_source.value.param_list()?;
let FileRange { file_id, range } = fn_source.syntax().original_file_range(ctx.sema.db);
if file_id == ctx.file_id() && range.contains(ctx.offset()) {
cov_mark::hit!(inline_call_recursive);
return None;
}
let params = get_fn_params(ctx.sema.db, function, &param_list)?;
if call_info.arguments.len() != params.len() {
// Can't inline the function because they've passed the wrong number of
// arguments to this function
cov_mark::hit!(inline_call_incorrect_number_of_arguments);
return None;
}
let syntax = call_info.node.syntax().clone();
acc.add(
AssistId("inline_call", AssistKind::RefactorInline),
label,
syntax.text_range(),
|builder| {
let replacement = inline(&ctx.sema, file_id, function, &fn_body, &params, &call_info);
builder.replace_ast(
match call_info.node {
ast::CallableExpr::Call(it) => ast::Expr::CallExpr(it),
ast::CallableExpr::MethodCall(it) => ast::Expr::MethodCallExpr(it),
},
replacement,
);
},
)
}
struct CallInfo {
node: ast::CallableExpr,
arguments: Vec<ast::Expr>,
generic_arg_list: Option<ast::GenericArgList>,
}
impl CallInfo {
fn from_name_ref(name_ref: ast::NameRef) -> Option<CallInfo> {
let parent = name_ref.syntax().parent()?;
if let Some(call) = ast::MethodCallExpr::cast(parent.clone()) {
let receiver = call.receiver()?;
let mut arguments = vec![receiver];
arguments.extend(call.arg_list()?.args());
Some(CallInfo {
generic_arg_list: call.generic_arg_list(),
node: ast::CallableExpr::MethodCall(call),
arguments,
})
} else if let Some(segment) = ast::PathSegment::cast(parent) {
let path = segment.syntax().parent().and_then(ast::Path::cast)?;
let path = path.syntax().parent().and_then(ast::PathExpr::cast)?;
let call = path.syntax().parent().and_then(ast::CallExpr::cast)?;
Some(CallInfo {
arguments: call.arg_list()?.args().collect(),
node: ast::CallableExpr::Call(call),
generic_arg_list: segment.generic_arg_list(),
})
} else {
None
}
}
}
fn get_fn_params(
db: &dyn HirDatabase,
function: hir::Function,
param_list: &ast::ParamList,
) -> Option<Vec<(ast::Pat, Option<ast::Type>, hir::Param)>> {
let mut assoc_fn_params = function.assoc_fn_params(db).into_iter();
let mut params = Vec::new();
if let Some(self_param) = param_list.self_param() {
// FIXME this should depend on the receiver as well as the self_param
params.push((
make::ident_pat(
self_param.amp_token().is_some(),
self_param.mut_token().is_some(),
make::name("this"),
)
.into(),
None,
assoc_fn_params.next()?,
));
}
for param in param_list.params() {
params.push((param.pat()?, param.ty(), assoc_fn_params.next()?));
}
Some(params)
}
fn inline(
sema: &Semantics<RootDatabase>,
function_def_file_id: FileId,
function: hir::Function,
fn_body: &ast::BlockExpr,
params: &[(ast::Pat, Option<ast::Type>, hir::Param)],
CallInfo { node, arguments, generic_arg_list }: &CallInfo,
) -> ast::Expr {
let body = fn_body.clone_for_update();
let usages_for_locals = |local| {
Definition::Local(local)
.usages(&sema)
.all()
.references
.remove(&function_def_file_id)
.unwrap_or_default()
.into_iter()
};
let param_use_nodes: Vec<Vec<_>> = params
.iter()
.map(|(pat, _, param)| {
if !matches!(pat, ast::Pat::IdentPat(pat) if pat.is_simple_ident()) {
return Vec::new();
}
usages_for_locals(param.as_local(sema.db))
.map(|FileReference { name, range, .. }| match name {
ast::NameLike::NameRef(_) => body
.syntax()
.covering_element(range)
.ancestors()
.nth(3)
.and_then(ast::PathExpr::cast),
_ => None,
})
.collect::<Option<Vec<_>>>()
.unwrap_or_default()
})
.collect();
if function.self_param(sema.db).is_some() {
let this = || make::name_ref("this").syntax().clone_for_update();
usages_for_locals(params[0].2.as_local(sema.db))
.flat_map(|FileReference { name, range, .. }| match name {
ast::NameLike::NameRef(_) => Some(body.syntax().covering_element(range)),
_ => None,
})
.for_each(|it| {
ted::replace(it, &this());
})
}
// Inline parameter expressions or generate `let` statements depending on whether inlining works or not.
for ((pat, param_ty, _), usages, expr) in izip!(params, param_use_nodes, arguments).rev() {
let inline_direct = |usage, replacement: &ast::Expr| {
if let Some(field) = path_expr_as_record_field(usage) {
cov_mark::hit!(inline_call_inline_direct_field);
field.replace_expr(replacement.clone_for_update());
} else {
ted::replace(usage.syntax(), &replacement.syntax().clone_for_update());
}
};
// izip confuses RA due to our lack of hygiene info currently losing us type info causing incorrect errors
let usages: &[ast::PathExpr] = &*usages;
let expr: &ast::Expr = expr;
match usages {
// inline single use closure arguments
[usage]
if matches!(expr, ast::Expr::ClosureExpr(_))
&& usage.syntax().parent().and_then(ast::Expr::cast).is_some() =>
{
cov_mark::hit!(inline_call_inline_closure);
let expr = make::expr_paren(expr.clone());
inline_direct(usage, &expr);
}
// inline single use literals
[usage] if matches!(expr, ast::Expr::Literal(_)) => {
cov_mark::hit!(inline_call_inline_literal);
inline_direct(usage, &expr);
}
// inline direct local arguments
[_, ..] if expr_as_name_ref(&expr).is_some() => {
cov_mark::hit!(inline_call_inline_locals);
usages.into_iter().for_each(|usage| inline_direct(usage, &expr));
}
// can't inline, emit a let statement
_ => {
let ty =
sema.type_of_expr(expr).filter(TypeInfo::has_adjustment).and(param_ty.clone());
if let Some(stmt_list) = body.stmt_list() {
stmt_list.push_front(
make::let_stmt(pat.clone(), ty, Some(expr.clone()))
.clone_for_update()
.into(),
)
}
}
}
}
if let Some(generic_arg_list) = generic_arg_list.clone() {
PathTransform::function_call(
&sema.scope(node.syntax()),
&sema.scope(fn_body.syntax()),
function,
generic_arg_list,
)
.apply(body.syntax());
}
let original_indentation = match node {
ast::CallableExpr::Call(it) => it.indent_level(),
ast::CallableExpr::MethodCall(it) => it.indent_level(),
};
body.reindent_to(original_indentation);
match body.tail_expr() {
Some(expr) if body.statements().next().is_none() => expr,
_ => ast::Expr::BlockExpr(body),
}
}
fn path_expr_as_record_field(usage: &PathExpr) -> Option<ast::RecordExprField> {
let path = usage.path()?;
let name_ref = path.as_single_name_ref()?;
ast::RecordExprField::for_name_ref(&name_ref)
}
#[cfg(test)]
mod tests {
use crate::tests::{check_assist, check_assist_not_applicable};
use super::*;
#[test]
fn no_args_or_return_value_gets_inlined_without_block() {
check_assist(
inline_call,
r#"
fn foo() { println!("Hello, World!"); }
fn main() {
fo$0o();
}
"#,
r#"
fn foo() { println!("Hello, World!"); }
fn main() {
{ println!("Hello, World!"); };
}
"#,
);
}
#[test]
fn not_applicable_when_incorrect_number_of_parameters_are_provided() {
cov_mark::check!(inline_call_incorrect_number_of_arguments);
check_assist_not_applicable(
inline_call,
r#"
fn add(a: u32, b: u32) -> u32 { a + b }
fn main() { let x = add$0(42); }
"#,
);
}
#[test]
fn args_with_side_effects() {
check_assist(
inline_call,
r#"
fn foo(name: String) {
println!("Hello, {}!", name);
}
fn main() {
foo$0(String::from("Michael"));
}
"#,
r#"
fn foo(name: String) {
println!("Hello, {}!", name);
}
fn main() {
{
let name = String::from("Michael");
println!("Hello, {}!", name);
};
}
"#,
);
}
#[test]
fn function_with_multiple_statements() {
check_assist(
inline_call,
r#"
fn foo(a: u32, b: u32) -> u32 {
let x = a + b;
let y = x - b;
x * y
}
fn main() {
let x = foo$0(1, 2);
}
"#,
r#"
fn foo(a: u32, b: u32) -> u32 {
let x = a + b;
let y = x - b;
x * y
}
fn main() {
let x = {
let b = 2;
let x = 1 + b;
let y = x - b;
x * y
};
}
"#,
);
}
#[test]
fn function_with_self_param() {
check_assist(
inline_call,
r#"
struct Foo(u32);
impl Foo {
fn add(self, a: u32) -> Self {
Foo(self.0 + a)
}
}
fn main() {
let x = Foo::add$0(Foo(3), 2);
}
"#,
r#"
struct Foo(u32);
impl Foo {
fn add(self, a: u32) -> Self {
Foo(self.0 + a)
}
}
fn main() {
let x = {
let this = Foo(3);
Foo(this.0 + 2)
};
}
"#,
);
}
#[test]
fn method_by_val() {
check_assist(
inline_call,
r#"
struct Foo(u32);
impl Foo {
fn add(self, a: u32) -> Self {
Foo(self.0 + a)
}
}
fn main() {
let x = Foo(3).add$0(2);
}
"#,
r#"
struct Foo(u32);
impl Foo {
fn add(self, a: u32) -> Self {
Foo(self.0 + a)
}
}
fn main() {
let x = {
let this = Foo(3);
Foo(this.0 + 2)
};
}
"#,
);
}
#[test]
fn method_by_ref() {
check_assist(
inline_call,
r#"
struct Foo(u32);
impl Foo {
fn add(&self, a: u32) -> Self {
Foo(self.0 + a)
}
}
fn main() {
let x = Foo(3).add$0(2);
}
"#,
r#"
struct Foo(u32);
impl Foo {
fn add(&self, a: u32) -> Self {
Foo(self.0 + a)
}
}
fn main() {
let x = {
let ref this = Foo(3);
Foo(this.0 + 2)
};
}
"#,
);
}
#[test]
fn method_by_ref_mut() {
check_assist(
inline_call,
r#"
struct Foo(u32);
impl Foo {
fn clear(&mut self) {
self.0 = 0;
}
}
fn main() {
let mut foo = Foo(3);
foo.clear$0();
}
"#,
r#"
struct Foo(u32);
impl Foo {
fn clear(&mut self) {
self.0 = 0;
}
}
fn main() {
let mut foo = Foo(3);
{
let ref mut this = foo;
this.0 = 0;
};
}
"#,
);
}
#[test]
fn function_multi_use_expr_in_param() {
check_assist(
inline_call,
r#"
fn square(x: u32) -> u32 {
x * x
}
fn main() {
let x = 51;
let y = square$0(10 + x);
}
"#,
r#"
fn square(x: u32) -> u32 {
x * x
}
fn main() {
let x = 51;
let y = {
let x = 10 + x;
x * x
};
}
"#,
);
}
#[test]
fn function_use_local_in_param() {
cov_mark::check!(inline_call_inline_locals);
check_assist(
inline_call,
r#"
fn square(x: u32) -> u32 {
x * x
}
fn main() {
let local = 51;
let y = square$0(local);
}
"#,
r#"
fn square(x: u32) -> u32 {
x * x
}
fn main() {
let local = 51;
let y = local * local;
}
"#,
);
}
#[test]
fn method_in_impl() {
check_assist(
inline_call,
r#"
struct Foo;
impl Foo {
fn foo(&self) {
self;
self;
}
fn bar(&self) {
self.foo$0();
}
}
"#,
r#"
struct Foo;
impl Foo {
fn foo(&self) {
self;
self;
}
fn bar(&self) {
{
let ref this = self;
this;
this;
};
}
}
"#,
);
}
#[test]
fn wraps_closure_in_paren() {
cov_mark::check!(inline_call_inline_closure);
check_assist(
inline_call,
r#"
fn foo(x: fn()) {
x();
}
fn main() {
foo$0(|| {})
}
"#,
r#"
fn foo(x: fn()) {
x();
}
fn main() {
{
(|| {})();
}
}
"#,
);
check_assist(
inline_call,
r#"
fn foo(x: fn()) {
x();
}
fn main() {
foo$0(main)
}
"#,
r#"
fn foo(x: fn()) {
x();
}
fn main() {
{
main();
}
}
"#,
);
}
#[test]
fn inline_single_literal_expr() {
cov_mark::check!(inline_call_inline_literal);
check_assist(
inline_call,
r#"
fn foo(x: u32) -> u32{
x
}
fn main() {
foo$0(222);
}
"#,
r#"
fn foo(x: u32) -> u32{
x
}
fn main() {
222;
}
"#,
);
}
#[test]
fn inline_emits_type_for_coercion() {
check_assist(
inline_call,
r#"
fn foo(x: *const u32) -> u32 {
x as u32
}
fn main() {
foo$0(&222);
}
"#,
r#"
fn foo(x: *const u32) -> u32 {
x as u32
}
fn main() {
{
let x: *const u32 = &222;
x as u32
};
}
"#,
);
}
// FIXME: const generics aren't being substituted, this is blocked on better support for them
#[test]
fn inline_substitutes_generics() {
check_assist(
inline_call,
r#"
fn foo<T, const N: usize>() {
bar::<T, N>()
}
fn bar<U, const M: usize>() {}
fn main() {
foo$0::<usize, {0}>();
}
"#,
r#"
fn foo<T, const N: usize>() {
bar::<T, N>()
}
fn bar<U, const M: usize>() {}
fn main() {
bar::<usize, N>();
}
"#,
);
}
#[test]
fn inline_callers() {
check_assist(
inline_into_callers,
r#"
fn do_the_math$0(b: u32) -> u32 {
let foo = 10;
foo * b + foo
}
fn foo() {
do_the_math(0);
let bar = 10;
do_the_math(bar);
}
"#,
r#"
fn foo() {
{
let foo = 10;
foo * 0 + foo
};
let bar = 10;
{
let foo = 10;
foo * bar + foo
};
}
"#,
);
}
#[test]
fn inline_callers_across_files() {
check_assist(
inline_into_callers,
r#"
//- /lib.rs
mod foo;
fn do_the_math$0(b: u32) -> u32 {
let foo = 10;
foo * b + foo
}
//- /foo.rs
use super::do_the_math;
fn foo() {
do_the_math(0);
let bar = 10;
do_the_math(bar);
}
"#,
r#"
//- /lib.rs
mod foo;
//- /foo.rs
fn foo() {
{
let foo = 10;
foo * 0 + foo
};
let bar = 10;
{
let foo = 10;
foo * bar + foo
};
}
"#,
);
}
#[test]
fn inline_callers_across_files_with_def_file() {
check_assist(
inline_into_callers,
r#"
//- /lib.rs
mod foo;
fn do_the_math$0(b: u32) -> u32 {
let foo = 10;
foo * b + foo
}
fn bar(a: u32, b: u32) -> u32 {
do_the_math(0);
}
//- /foo.rs
use super::do_the_math;
fn foo() {
do_the_math(0);
}
"#,
r#"
//- /lib.rs
mod foo;
fn bar(a: u32, b: u32) -> u32 {
{
let foo = 10;
foo * 0 + foo
};
}
//- /foo.rs
fn foo() {
{
let foo = 10;
foo * 0 + foo
};
}
"#,
);
}
#[test]
fn inline_callers_recursive() {
cov_mark::check!(inline_into_callers_recursive);
check_assist_not_applicable(
inline_into_callers,
r#"
fn foo$0() {
foo();
}
"#,
);
}
#[test]
fn inline_call_recursive() {
cov_mark::check!(inline_call_recursive);
check_assist_not_applicable(
inline_call,
r#"
fn foo() {
foo$0();
}
"#,
);
}
#[test]
fn inline_call_field_shorthand() {
cov_mark::check!(inline_call_inline_direct_field);
check_assist(
inline_call,
r#"
struct Foo {
field: u32,
field1: u32,
field2: u32,
field3: u32,
}
fn foo(field: u32, field1: u32, val2: u32, val3: u32) -> Foo {
Foo {
field,
field1,
field2: val2,
field3: val3,
}
}
fn main() {
let bar = 0;
let baz = 0;
foo$0(bar, 0, baz, 0);
}
"#,
r#"
struct Foo {
field: u32,
field1: u32,
field2: u32,
field3: u32,
}
fn foo(field: u32, field1: u32, val2: u32, val3: u32) -> Foo {
Foo {
field,
field1,
field2: val2,
field3: val3,
}
}
fn main() {
let bar = 0;
let baz = 0;
Foo {
field: bar,
field1: 0,
field2: baz,
field3: 0,
};
}
"#,
);
}
}