9474: fix: Inline parameters in `inline_call` if possible r=Veykril a=Veykril

Fixes #9491

Co-authored-by: Lukas Wirth <lukastw97@gmail.com>
This commit is contained in:
bors[bot] 2021-07-05 11:50:18 +00:00 committed by GitHub
commit 2bc4f9e371
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GPG Key ID: 4AEE18F83AFDEB23
5 changed files with 267 additions and 78 deletions

View File

@ -1,5 +1,7 @@
use ast::make;
use hir::{HasSource, PathResolution};
use ide_db::{defs::Definition, search::FileReference};
use itertools::izip;
use syntax::{
ast::{self, edit::AstNodeEdit, ArgListOwner},
ted, AstNode,
@ -15,19 +17,22 @@ use crate::{
// Inlines a function or method body.
//
// ```
// fn add(a: u32, b: u32) -> u32 { a + b }
// fn align(a: u32, b: u32) -> u32 {
// (a + b - 1) & !(b - 1)
// }
// fn main() {
// let x = add$0(1, 2);
// let x = align$0(1, 2);
// }
// ```
// ->
// ```
// fn add(a: u32, b: u32) -> u32 { a + b }
// fn align(a: u32, b: u32) -> u32 {
// (a + b - 1) & !(b - 1)
// }
// fn main() {
// let x = {
// let a = 1;
// let b = 2;
// a + b
// (1 + b - 1) & !(b - 1)
// };
// }
// ```
@ -69,23 +74,25 @@ pub(crate) fn inline_(
arg_list: Vec<ast::Expr>,
expr: ast::Expr,
) -> Option<()> {
let hir::InFile { value: function_source, .. } = function.source(ctx.db())?;
let hir::InFile { value: function_source, file_id } = function.source(ctx.db())?;
let param_list = function_source.param_list()?;
let mut assoc_fn_params = function.assoc_fn_params(ctx.sema.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(
params.push((
make::ident_pat(
self_param.amp_token().is_some(),
self_param.mut_token().is_some(),
make::name("this"),
)
.into(),
);
assoc_fn_params.next()?,
));
}
for param in param_list.params() {
params.push(param.pat()?);
params.push((param.pat()?, assoc_fn_params.next()?));
}
if arg_list.len() != params.len() {
@ -95,8 +102,6 @@ pub(crate) fn inline_(
return None;
}
let new_bindings = params.into_iter().zip(arg_list);
let body = function_source.body()?;
acc.add(
@ -104,32 +109,87 @@ pub(crate) fn inline_(
label,
expr.syntax().text_range(),
|builder| {
let body = body.clone_for_update();
let file_id = file_id.original_file(ctx.sema.db);
let usages_for_locals = |local| {
Definition::Local(local)
.usages(&ctx.sema)
.all()
.references
.remove(&file_id)
.unwrap_or_default()
.into_iter()
};
// Contains the nodes of usages of parameters.
// If the inner Vec for a parameter is empty it either means there are no usages or that the parameter
// has a pattern that does not allow inlining
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(ctx.sema.db))
.map(|FileReference { name, range, .. }| match name {
ast::NameLike::NameRef(_) => body
.syntax()
.covering_element(range)
.ancestors()
.nth(3)
.filter(|it| ast::PathExpr::can_cast(it.kind())),
_ => None,
})
.collect::<Option<Vec<_>>>()
.unwrap_or_default()
})
.collect();
// Rewrite `self` to `this`
if param_list.self_param().is_some() {
let this = || make::name_ref("this").syntax().clone_for_update();
usages_for_locals(params[0].1.as_local(ctx.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, _), usages, expr) in izip!(params, param_use_nodes, arg_list).rev() {
match &*usages {
// inline single use parameters
[usage] => {
ted::replace(usage, expr.syntax().clone_for_update());
}
// inline parameters whose expression is a simple local reference
[_, ..]
if matches!(&expr,
ast::Expr::PathExpr(expr)
if expr.path().and_then(|path| path.as_single_name_ref()).is_some()
) =>
{
usages.into_iter().for_each(|usage| {
ted::replace(usage, &expr.syntax().clone_for_update());
});
}
// cant inline, emit a let statement
// FIXME: emit type ascriptions when a coercion happens?
// FIXME: dont create locals when its not required
let statements = new_bindings
.map(|(pattern, value)| make::let_stmt(pattern, Some(value)).into())
.chain(body.statements());
_ => body.push_front(make::let_stmt(pat, Some(expr)).clone_for_update().into()),
}
}
let original_indentation = expr.indent_level();
let mut replacement = make::block_expr(statements, body.tail_expr())
.reset_indent()
.indent(original_indentation);
let replacement = body.reset_indent().indent(original_indentation);
if param_list.self_param().is_some() {
replacement = replacement.clone_for_update();
let this = make::name_ref("this").syntax().clone_for_update();
// FIXME dont look into descendant methods
replacement
.syntax()
.descendants()
.filter_map(ast::NameRef::cast)
.filter(|n| n.self_token().is_some())
.collect::<Vec<_>>()
.into_iter()
.rev()
.for_each(|self_ref| ted::replace(self_ref.syntax(), &this));
}
builder.replace_ast(expr, ast::Expr::BlockExpr(replacement));
let replacement = match replacement.tail_expr() {
Some(expr) if replacement.statements().next().is_none() => expr,
_ => ast::Expr::BlockExpr(replacement),
};
builder.replace_ast(expr, replacement);
},
)
}
@ -153,31 +213,7 @@ fn main() {
r#"
fn foo() { println!("Hello, World!"); }
fn main() {
{
println!("Hello, World!");
};
}
"#,
);
}
#[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);
};
{ println!("Hello, World!"); };
}
"#,
);
@ -195,6 +231,32 @@ 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(
@ -219,9 +281,8 @@ fn foo(a: u32, b: u32) -> u32 {
fn main() {
let x = {
let a = 1;
let b = 2;
let x = a + b;
let x = 1 + b;
let y = x - b;
x * y
};
@ -257,11 +318,7 @@ impl Foo {
}
fn main() {
let x = {
let this = Foo(3);
let a = 2;
Foo(this.0 + a)
};
let x = Foo(Foo(3).0 + 2);
}
"#,
);
@ -294,11 +351,7 @@ impl Foo {
}
fn main() {
let x = {
let this = Foo(3);
let a = 2;
Foo(this.0 + a)
};
let x = Foo(Foo(3).0 + 2);
}
"#,
);
@ -333,8 +386,7 @@ impl Foo {
fn main() {
let x = {
let ref this = Foo(3);
let a = 2;
Foo(this.0 + a)
Foo(this.0 + 2)
};
}
"#,
@ -375,6 +427,119 @@ fn main() {
this.0 = 0;
};
}
"#,
);
}
#[test]
fn function_single_use_expr_in_param() {
check_assist(
inline_call,
r#"
fn double(x: u32) -> u32 {
2 * x
}
fn main() {
let x = 51;
let x = double$0(10 + x);
}
"#,
r#"
fn double(x: u32) -> u32 {
2 * x
}
fn main() {
let x = 51;
let x = 2 * 10 + x;
}
"#,
);
}
#[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_multi_use_local_in_param() {
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;
};
}
}
"#,
);
}

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@ -923,18 +923,21 @@ fn doctest_inline_call() {
check_doc_test(
"inline_call",
r#####"
fn add(a: u32, b: u32) -> u32 { a + b }
fn align(a: u32, b: u32) -> u32 {
(a + b - 1) & !(b - 1)
}
fn main() {
let x = add$0(1, 2);
let x = align$0(1, 2);
}
"#####,
r#####"
fn add(a: u32, b: u32) -> u32 { a + b }
fn align(a: u32, b: u32) -> u32 {
(a + b - 1) & !(b - 1)
}
fn main() {
let x = {
let a = 1;
let b = 2;
a + b
(1 + b - 1) & !(b - 1)
};
}
"#####,

View File

@ -431,6 +431,12 @@ impl ast::RecordExprFieldList {
}
}
impl ast::BlockExpr {
pub fn push_front(&self, statement: ast::Stmt) {
ted::insert(Position::after(self.l_curly_token().unwrap()), statement.syntax());
}
}
fn normalize_ws_between_braces(node: &SyntaxNode) -> Option<()> {
let l = node
.children_with_tokens()

View File

@ -641,6 +641,15 @@ impl ast::SlicePat {
}
}
impl ast::IdentPat {
pub fn is_simple_ident(&self) -> bool {
self.at_token().is_none()
&& self.mut_token().is_none()
&& self.ref_token().is_none()
&& self.pat().is_none()
}
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub enum SelfParamKind {
/// self

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@ -187,6 +187,12 @@ fn ws_between(left: &SyntaxElement, right: &SyntaxElement) -> Option<SyntaxToken
return None;
}
if left.kind() == T!['{'] && right.kind() == SyntaxKind::LET_STMT {
let mut indent = IndentLevel::from_element(left);
indent.0 += 1;
return Some(make::tokens::whitespace(&format!("\n{}", indent)));
}
if right.kind() == SyntaxKind::USE {
let mut indent = IndentLevel::from_element(left);
if left.kind() == SyntaxKind::USE {