rust-analyzer/crates/ide/src/diagnostics.rs
2020-08-13 17:58:27 +02:00

678 lines
18 KiB
Rust

//! Collects diagnostics & fixits for a single file.
//!
//! The tricky bit here is that diagnostics are produced by hir in terms of
//! macro-expanded files, but we need to present them to the users in terms of
//! original files. So we need to map the ranges.
use std::cell::RefCell;
use base_db::SourceDatabase;
use hir::{diagnostics::DiagnosticSinkBuilder, Semantics};
use ide_db::RootDatabase;
use itertools::Itertools;
use syntax::{
ast::{self, AstNode},
SyntaxNode, TextRange, T,
};
use text_edit::TextEdit;
use crate::{Diagnostic, FileId, Fix, SourceFileEdit};
mod diagnostics_with_fix;
use diagnostics_with_fix::DiagnosticWithFix;
#[derive(Debug, Copy, Clone)]
pub enum Severity {
Error,
WeakWarning,
}
pub(crate) fn diagnostics(
db: &RootDatabase,
file_id: FileId,
enable_experimental: bool,
) -> Vec<Diagnostic> {
let _p = profile::span("diagnostics");
let sema = Semantics::new(db);
let parse = db.parse(file_id);
let mut res = Vec::new();
// [#34344] Only take first 128 errors to prevent slowing down editor/ide, the number 128 is chosen arbitrarily.
res.extend(parse.errors().iter().take(128).map(|err| Diagnostic {
range: err.range(),
message: format!("Syntax Error: {}", err),
severity: Severity::Error,
fix: None,
}));
for node in parse.tree().syntax().descendants() {
check_unnecessary_braces_in_use_statement(&mut res, file_id, &node);
check_struct_shorthand_initialization(&mut res, file_id, &node);
}
let res = RefCell::new(res);
let mut sink = DiagnosticSinkBuilder::new()
.on::<hir::diagnostics::UnresolvedModule, _>(|d| {
res.borrow_mut().push(diagnostic_with_fix(d, &sema));
})
.on::<hir::diagnostics::MissingFields, _>(|d| {
res.borrow_mut().push(diagnostic_with_fix(d, &sema));
})
.on::<hir::diagnostics::MissingOkInTailExpr, _>(|d| {
res.borrow_mut().push(diagnostic_with_fix(d, &sema));
})
.on::<hir::diagnostics::NoSuchField, _>(|d| {
res.borrow_mut().push(diagnostic_with_fix(d, &sema));
})
// Only collect experimental diagnostics when they're enabled.
.filter(|diag| !diag.is_experimental() || enable_experimental)
// Diagnostics not handled above get no fix and default treatment.
.build(|d| {
res.borrow_mut().push(Diagnostic {
message: d.message(),
range: sema.diagnostics_display_range(d).range,
severity: Severity::Error,
fix: None,
})
});
if let Some(m) = sema.to_module_def(file_id) {
m.diagnostics(db, &mut sink);
};
drop(sink);
res.into_inner()
}
fn diagnostic_with_fix<D: DiagnosticWithFix>(d: &D, sema: &Semantics<RootDatabase>) -> Diagnostic {
Diagnostic {
range: sema.diagnostics_display_range(d).range,
message: d.message(),
severity: Severity::Error,
fix: d.fix(&sema),
}
}
fn check_unnecessary_braces_in_use_statement(
acc: &mut Vec<Diagnostic>,
file_id: FileId,
node: &SyntaxNode,
) -> Option<()> {
let use_tree_list = ast::UseTreeList::cast(node.clone())?;
if let Some((single_use_tree,)) = use_tree_list.use_trees().collect_tuple() {
let use_range = use_tree_list.syntax().text_range();
let edit =
text_edit_for_remove_unnecessary_braces_with_self_in_use_statement(&single_use_tree)
.unwrap_or_else(|| {
let to_replace = single_use_tree.syntax().text().to_string();
let mut edit_builder = TextEdit::builder();
edit_builder.delete(use_range);
edit_builder.insert(use_range.start(), to_replace);
edit_builder.finish()
});
acc.push(Diagnostic {
range: use_range,
message: "Unnecessary braces in use statement".to_string(),
severity: Severity::WeakWarning,
fix: Some(Fix::new(
"Remove unnecessary braces",
SourceFileEdit { file_id, edit }.into(),
use_range,
)),
});
}
Some(())
}
fn text_edit_for_remove_unnecessary_braces_with_self_in_use_statement(
single_use_tree: &ast::UseTree,
) -> Option<TextEdit> {
let use_tree_list_node = single_use_tree.syntax().parent()?;
if single_use_tree.path()?.segment()?.syntax().first_child_or_token()?.kind() == T![self] {
let start = use_tree_list_node.prev_sibling_or_token()?.text_range().start();
let end = use_tree_list_node.text_range().end();
return Some(TextEdit::delete(TextRange::new(start, end)));
}
None
}
fn check_struct_shorthand_initialization(
acc: &mut Vec<Diagnostic>,
file_id: FileId,
node: &SyntaxNode,
) -> Option<()> {
let record_lit = ast::RecordExpr::cast(node.clone())?;
let record_field_list = record_lit.record_expr_field_list()?;
for record_field in record_field_list.fields() {
if let (Some(name_ref), Some(expr)) = (record_field.name_ref(), record_field.expr()) {
let field_name = name_ref.syntax().text().to_string();
let field_expr = expr.syntax().text().to_string();
let field_name_is_tup_index = name_ref.as_tuple_field().is_some();
if field_name == field_expr && !field_name_is_tup_index {
let mut edit_builder = TextEdit::builder();
edit_builder.delete(record_field.syntax().text_range());
edit_builder.insert(record_field.syntax().text_range().start(), field_name);
let edit = edit_builder.finish();
let field_range = record_field.syntax().text_range();
acc.push(Diagnostic {
range: field_range,
message: "Shorthand struct initialization".to_string(),
severity: Severity::WeakWarning,
fix: Some(Fix::new(
"Use struct shorthand initialization",
SourceFileEdit { file_id, edit }.into(),
field_range,
)),
});
}
}
}
Some(())
}
#[cfg(test)]
mod tests {
use stdx::trim_indent;
use test_utils::assert_eq_text;
use crate::mock_analysis::{analysis_and_position, single_file, MockAnalysis};
use expect::{expect, Expect};
/// Takes a multi-file input fixture with annotated cursor positions,
/// and checks that:
/// * a diagnostic is produced
/// * this diagnostic fix trigger range touches the input cursor position
/// * that the contents of the file containing the cursor match `after` after the diagnostic fix is applied
fn check_fix(ra_fixture_before: &str, ra_fixture_after: &str) {
let after = trim_indent(ra_fixture_after);
let (analysis, file_position) = analysis_and_position(ra_fixture_before);
let diagnostic = analysis.diagnostics(file_position.file_id, true).unwrap().pop().unwrap();
let mut fix = diagnostic.fix.unwrap();
let edit = fix.source_change.source_file_edits.pop().unwrap().edit;
let target_file_contents = analysis.file_text(file_position.file_id).unwrap();
let actual = {
let mut actual = target_file_contents.to_string();
edit.apply(&mut actual);
actual
};
assert_eq_text!(&after, &actual);
assert!(
fix.fix_trigger_range.start() <= file_position.offset
&& fix.fix_trigger_range.end() >= file_position.offset,
"diagnostic fix range {:?} does not touch cursor position {:?}",
fix.fix_trigger_range,
file_position.offset
);
}
/// Checks that a diagnostic applies to the file containing the `<|>` cursor marker
/// which has a fix that can apply to other files.
fn check_apply_diagnostic_fix_in_other_file(ra_fixture_before: &str, ra_fixture_after: &str) {
let ra_fixture_after = &trim_indent(ra_fixture_after);
let (analysis, file_pos) = analysis_and_position(ra_fixture_before);
let current_file_id = file_pos.file_id;
let diagnostic = analysis.diagnostics(current_file_id, true).unwrap().pop().unwrap();
let mut fix = diagnostic.fix.unwrap();
let edit = fix.source_change.source_file_edits.pop().unwrap();
let changed_file_id = edit.file_id;
let before = analysis.file_text(changed_file_id).unwrap();
let actual = {
let mut actual = before.to_string();
edit.edit.apply(&mut actual);
actual
};
assert_eq_text!(ra_fixture_after, &actual);
}
/// Takes a multi-file input fixture with annotated cursor position and checks that no diagnostics
/// apply to the file containing the cursor.
fn check_no_diagnostics(ra_fixture: &str) {
let mock = MockAnalysis::with_files(ra_fixture);
let files = mock.files().map(|(it, _)| it).collect::<Vec<_>>();
let analysis = mock.analysis();
let diagnostics = files
.into_iter()
.flat_map(|file_id| analysis.diagnostics(file_id, true).unwrap())
.collect::<Vec<_>>();
assert_eq!(diagnostics.len(), 0, "unexpected diagnostics:\n{:#?}", diagnostics);
}
fn check_expect(ra_fixture: &str, expect: Expect) {
let (analysis, file_id) = single_file(ra_fixture);
let diagnostics = analysis.diagnostics(file_id, true).unwrap();
expect.assert_debug_eq(&diagnostics)
}
#[test]
fn test_wrap_return_type() {
check_fix(
r#"
//- /main.rs
use core::result::Result::{self, Ok, Err};
fn div(x: i32, y: i32) -> Result<i32, ()> {
if y == 0 {
return Err(());
}
x / y<|>
}
//- /core/lib.rs
pub mod result {
pub enum Result<T, E> { Ok(T), Err(E) }
}
"#,
r#"
use core::result::Result::{self, Ok, Err};
fn div(x: i32, y: i32) -> Result<i32, ()> {
if y == 0 {
return Err(());
}
Ok(x / y)
}
"#,
);
}
#[test]
fn test_wrap_return_type_handles_generic_functions() {
check_fix(
r#"
//- /main.rs
use core::result::Result::{self, Ok, Err};
fn div<T>(x: T) -> Result<T, i32> {
if x == 0 {
return Err(7);
}
<|>x
}
//- /core/lib.rs
pub mod result {
pub enum Result<T, E> { Ok(T), Err(E) }
}
"#,
r#"
use core::result::Result::{self, Ok, Err};
fn div<T>(x: T) -> Result<T, i32> {
if x == 0 {
return Err(7);
}
Ok(x)
}
"#,
);
}
#[test]
fn test_wrap_return_type_handles_type_aliases() {
check_fix(
r#"
//- /main.rs
use core::result::Result::{self, Ok, Err};
type MyResult<T> = Result<T, ()>;
fn div(x: i32, y: i32) -> MyResult<i32> {
if y == 0 {
return Err(());
}
x <|>/ y
}
//- /core/lib.rs
pub mod result {
pub enum Result<T, E> { Ok(T), Err(E) }
}
"#,
r#"
use core::result::Result::{self, Ok, Err};
type MyResult<T> = Result<T, ()>;
fn div(x: i32, y: i32) -> MyResult<i32> {
if y == 0 {
return Err(());
}
Ok(x / y)
}
"#,
);
}
#[test]
fn test_wrap_return_type_not_applicable_when_expr_type_does_not_match_ok_type() {
check_no_diagnostics(
r#"
//- /main.rs
use core::result::Result::{self, Ok, Err};
fn foo() -> Result<(), i32> { 0 }
//- /core/lib.rs
pub mod result {
pub enum Result<T, E> { Ok(T), Err(E) }
}
"#,
);
}
#[test]
fn test_wrap_return_type_not_applicable_when_return_type_is_not_result() {
check_no_diagnostics(
r#"
//- /main.rs
use core::result::Result::{self, Ok, Err};
enum SomeOtherEnum { Ok(i32), Err(String) }
fn foo() -> SomeOtherEnum { 0 }
//- /core/lib.rs
pub mod result {
pub enum Result<T, E> { Ok(T), Err(E) }
}
"#,
);
}
#[test]
fn test_fill_struct_fields_empty() {
check_fix(
r#"
struct TestStruct { one: i32, two: i64 }
fn test_fn() {
let s = TestStruct {<|>};
}
"#,
r#"
struct TestStruct { one: i32, two: i64 }
fn test_fn() {
let s = TestStruct { one: (), two: ()};
}
"#,
);
}
#[test]
fn test_fill_struct_fields_self() {
check_fix(
r#"
struct TestStruct { one: i32 }
impl TestStruct {
fn test_fn() { let s = Self {<|>}; }
}
"#,
r#"
struct TestStruct { one: i32 }
impl TestStruct {
fn test_fn() { let s = Self { one: ()}; }
}
"#,
);
}
#[test]
fn test_fill_struct_fields_enum() {
check_fix(
r#"
enum Expr {
Bin { lhs: Box<Expr>, rhs: Box<Expr> }
}
impl Expr {
fn new_bin(lhs: Box<Expr>, rhs: Box<Expr>) -> Expr {
Expr::Bin {<|> }
}
}
"#,
r#"
enum Expr {
Bin { lhs: Box<Expr>, rhs: Box<Expr> }
}
impl Expr {
fn new_bin(lhs: Box<Expr>, rhs: Box<Expr>) -> Expr {
Expr::Bin { lhs: (), rhs: () }
}
}
"#,
);
}
#[test]
fn test_fill_struct_fields_partial() {
check_fix(
r#"
struct TestStruct { one: i32, two: i64 }
fn test_fn() {
let s = TestStruct{ two: 2<|> };
}
"#,
r"
struct TestStruct { one: i32, two: i64 }
fn test_fn() {
let s = TestStruct{ two: 2, one: () };
}
",
);
}
#[test]
fn test_fill_struct_fields_no_diagnostic() {
check_no_diagnostics(
r"
struct TestStruct { one: i32, two: i64 }
fn test_fn() {
let one = 1;
let s = TestStruct{ one, two: 2 };
}
",
);
}
#[test]
fn test_fill_struct_fields_no_diagnostic_on_spread() {
check_no_diagnostics(
r"
struct TestStruct { one: i32, two: i64 }
fn test_fn() {
let one = 1;
let s = TestStruct{ ..a };
}
",
);
}
#[test]
fn test_unresolved_module_diagnostic() {
check_expect(
r#"mod foo;"#,
expect![[r#"
[
Diagnostic {
message: "unresolved module",
range: 0..8,
severity: Error,
fix: Some(
Fix {
label: "Create module",
source_change: SourceChange {
source_file_edits: [],
file_system_edits: [
CreateFile {
anchor: FileId(
1,
),
dst: "foo.rs",
},
],
is_snippet: false,
},
fix_trigger_range: 0..8,
},
),
},
]
"#]],
);
}
#[test]
fn range_mapping_out_of_macros() {
// FIXME: this is very wrong, but somewhat tricky to fix.
check_fix(
r#"
fn some() {}
fn items() {}
fn here() {}
macro_rules! id { ($($tt:tt)*) => { $($tt)*}; }
fn main() {
let _x = id![Foo { a: <|>42 }];
}
pub struct Foo { pub a: i32, pub b: i32 }
"#,
r#"
fn {a:42, b: ()} {}
fn items() {}
fn here() {}
macro_rules! id { ($($tt:tt)*) => { $($tt)*}; }
fn main() {
let _x = id![Foo { a: 42 }];
}
pub struct Foo { pub a: i32, pub b: i32 }
"#,
);
}
#[test]
fn test_check_unnecessary_braces_in_use_statement() {
check_no_diagnostics(
r#"
use a;
use a::{c, d::e};
"#,
);
check_fix(r#"use {<|>b};"#, r#"use b;"#);
check_fix(r#"use {b<|>};"#, r#"use b;"#);
check_fix(r#"use a::{c<|>};"#, r#"use a::c;"#);
check_fix(r#"use a::{self<|>};"#, r#"use a;"#);
check_fix(r#"use a::{c, d::{e<|>}};"#, r#"use a::{c, d::e};"#);
}
#[test]
fn test_check_struct_shorthand_initialization() {
check_no_diagnostics(
r#"
struct A { a: &'static str }
fn main() { A { a: "hello" } }
"#,
);
check_no_diagnostics(
r#"
struct A(usize);
fn main() { A { 0: 0 } }
"#,
);
check_fix(
r#"
struct A { a: &'static str }
fn main() {
let a = "haha";
A { a<|>: a }
}
"#,
r#"
struct A { a: &'static str }
fn main() {
let a = "haha";
A { a }
}
"#,
);
check_fix(
r#"
struct A { a: &'static str, b: &'static str }
fn main() {
let a = "haha";
let b = "bb";
A { a<|>: a, b }
}
"#,
r#"
struct A { a: &'static str, b: &'static str }
fn main() {
let a = "haha";
let b = "bb";
A { a, b }
}
"#,
);
}
#[test]
fn test_add_field_from_usage() {
check_fix(
r"
fn main() {
Foo { bar: 3, baz<|>: false};
}
struct Foo {
bar: i32
}
",
r"
fn main() {
Foo { bar: 3, baz: false};
}
struct Foo {
bar: i32,
baz: bool
}
",
)
}
#[test]
fn test_add_field_in_other_file_from_usage() {
check_apply_diagnostic_fix_in_other_file(
r"
//- /main.rs
mod foo;
fn main() {
<|>foo::Foo { bar: 3, baz: false};
}
//- /foo.rs
struct Foo {
bar: i32
}
",
r"
struct Foo {
bar: i32,
pub(crate) baz: bool
}
",
)
}
}