rust/crates/ide_diagnostics/src/lib.rs
2022-03-21 19:16:58 +01:00

243 lines
8.6 KiB
Rust

//! Diagnostics rendering and fixits.
//!
//! Most of the diagnostics originate from the dark depth of the compiler, and
//! are originally expressed in term of IR. When we emit the diagnostic, we are
//! usually not in the position to decide how to best "render" it in terms of
//! user-authored source code. We are especially not in the position to offer
//! fixits, as the compiler completely lacks the infrastructure to edit the
//! source code.
//!
//! Instead, we "bubble up" raw, structured diagnostics until the `hir` crate,
//! where we "cook" them so that each diagnostic is formulated in terms of `hir`
//! types. Well, at least that's the aspiration, the "cooking" is somewhat
//! ad-hoc at the moment. Anyways, we get a bunch of ide-friendly diagnostic
//! structs from hir, and we want to render them to unified serializable
//! representation (span, level, message) here. If we can, we also provide
//! fixits. By the way, that's why we want to keep diagnostics structured
//! internally -- so that we have all the info to make fixes.
//!
//! We have one "handler" module per diagnostic code. Such a module contains
//! rendering, optional fixes and tests. It's OK if some low-level compiler
//! functionality ends up being tested via a diagnostic.
//!
//! There are also a couple of ad-hoc diagnostics implemented directly here, we
//! don't yet have a great pattern for how to do them properly.
mod handlers {
pub(crate) mod break_outside_of_loop;
pub(crate) mod inactive_code;
pub(crate) mod incorrect_case;
pub(crate) mod invalid_derive_target;
pub(crate) mod macro_error;
pub(crate) mod malformed_derive;
pub(crate) mod mismatched_arg_count;
pub(crate) mod missing_fields;
pub(crate) mod missing_match_arms;
pub(crate) mod missing_unsafe;
pub(crate) mod no_such_field;
pub(crate) mod replace_filter_map_next_with_find_map;
pub(crate) mod type_mismatch;
pub(crate) mod unimplemented_builtin_macro;
pub(crate) mod unresolved_extern_crate;
pub(crate) mod unresolved_import;
pub(crate) mod unresolved_macro_call;
pub(crate) mod unresolved_module;
pub(crate) mod unresolved_proc_macro;
// The handlers below are unusual, the implement the diagnostics as well.
pub(crate) mod field_shorthand;
pub(crate) mod useless_braces;
pub(crate) mod unlinked_file;
}
#[cfg(test)]
mod tests;
use hir::{diagnostics::AnyDiagnostic, Semantics};
use ide_db::{
assists::{Assist, AssistId, AssistKind, AssistResolveStrategy},
base_db::{FileId, SourceDatabase},
label::Label,
source_change::SourceChange,
RootDatabase,
};
use rustc_hash::FxHashSet;
use syntax::{ast::AstNode, TextRange};
#[derive(Copy, Clone, Debug, PartialEq)]
pub struct DiagnosticCode(pub &'static str);
impl DiagnosticCode {
pub fn as_str(&self) -> &str {
self.0
}
}
#[derive(Debug)]
pub struct Diagnostic {
pub code: DiagnosticCode,
pub message: String,
pub range: TextRange,
pub severity: Severity,
pub unused: bool,
pub experimental: bool,
pub fixes: Option<Vec<Assist>>,
}
impl Diagnostic {
fn new(code: &'static str, message: impl Into<String>, range: TextRange) -> Diagnostic {
let message = message.into();
Diagnostic {
code: DiagnosticCode(code),
message,
range,
severity: Severity::Error,
unused: false,
experimental: false,
fixes: None,
}
}
fn experimental(mut self) -> Diagnostic {
self.experimental = true;
self
}
fn severity(mut self, severity: Severity) -> Diagnostic {
self.severity = severity;
self
}
fn with_fixes(mut self, fixes: Option<Vec<Assist>>) -> Diagnostic {
self.fixes = fixes;
self
}
fn with_unused(mut self, unused: bool) -> Diagnostic {
self.unused = unused;
self
}
}
#[derive(Debug, Copy, Clone)]
pub enum Severity {
Error,
// We don't actually emit this one yet, but we should at some point.
// Warning,
WeakWarning,
}
#[derive(Clone, Debug, PartialEq, Eq)]
pub enum ExprFillDefaultMode {
Todo,
Default,
}
impl Default for ExprFillDefaultMode {
fn default() -> Self {
Self::Todo
}
}
#[derive(Default, Debug, Clone)]
pub struct DiagnosticsConfig {
pub disable_experimental: bool,
pub disabled: FxHashSet<String>,
pub expr_fill_default: ExprFillDefaultMode,
}
struct DiagnosticsContext<'a> {
config: &'a DiagnosticsConfig,
sema: Semantics<'a, RootDatabase>,
resolve: &'a AssistResolveStrategy,
}
pub fn diagnostics(
db: &RootDatabase,
config: &DiagnosticsConfig,
resolve: &AssistResolveStrategy,
file_id: FileId,
) -> 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::new("syntax-error", format!("Syntax Error: {}", err), err.range())
}),
);
for node in parse.tree().syntax().descendants() {
handlers::useless_braces::useless_braces(&mut res, file_id, &node);
handlers::field_shorthand::field_shorthand(&mut res, file_id, &node);
}
let module = sema.to_module_def(file_id);
let ctx = DiagnosticsContext { config, sema, resolve };
if module.is_none() {
handlers::unlinked_file::unlinked_file(&ctx, &mut res, file_id);
}
let mut diags = Vec::new();
if let Some(m) = module {
m.diagnostics(db, &mut diags)
}
for diag in diags {
#[rustfmt::skip]
let d = match diag {
AnyDiagnostic::BreakOutsideOfLoop(d) => handlers::break_outside_of_loop::break_outside_of_loop(&ctx, &d),
AnyDiagnostic::IncorrectCase(d) => handlers::incorrect_case::incorrect_case(&ctx, &d),
AnyDiagnostic::MacroError(d) => handlers::macro_error::macro_error(&ctx, &d),
AnyDiagnostic::MalformedDerive(d) => handlers::malformed_derive::malformed_derive(&ctx, &d),
AnyDiagnostic::MismatchedArgCount(d) => handlers::mismatched_arg_count::mismatched_arg_count(&ctx, &d),
AnyDiagnostic::MissingFields(d) => handlers::missing_fields::missing_fields(&ctx, &d),
AnyDiagnostic::MissingMatchArms(d) => handlers::missing_match_arms::missing_match_arms(&ctx, &d),
AnyDiagnostic::MissingUnsafe(d) => handlers::missing_unsafe::missing_unsafe(&ctx, &d),
AnyDiagnostic::NoSuchField(d) => handlers::no_such_field::no_such_field(&ctx, &d),
AnyDiagnostic::ReplaceFilterMapNextWithFindMap(d) => handlers::replace_filter_map_next_with_find_map::replace_filter_map_next_with_find_map(&ctx, &d),
AnyDiagnostic::TypeMismatch(d) => handlers::type_mismatch::type_mismatch(&ctx, &d),
AnyDiagnostic::UnimplementedBuiltinMacro(d) => handlers::unimplemented_builtin_macro::unimplemented_builtin_macro(&ctx, &d),
AnyDiagnostic::UnresolvedExternCrate(d) => handlers::unresolved_extern_crate::unresolved_extern_crate(&ctx, &d),
AnyDiagnostic::UnresolvedImport(d) => handlers::unresolved_import::unresolved_import(&ctx, &d),
AnyDiagnostic::UnresolvedMacroCall(d) => handlers::unresolved_macro_call::unresolved_macro_call(&ctx, &d),
AnyDiagnostic::UnresolvedModule(d) => handlers::unresolved_module::unresolved_module(&ctx, &d),
AnyDiagnostic::UnresolvedProcMacro(d) => handlers::unresolved_proc_macro::unresolved_proc_macro(&ctx, &d),
AnyDiagnostic::InvalidDeriveTarget(d) => handlers::invalid_derive_target::invalid_derive_target(&ctx, &d),
AnyDiagnostic::InactiveCode(d) => match handlers::inactive_code::inactive_code(&ctx, &d) {
Some(it) => it,
None => continue,
}
};
res.push(d)
}
res.retain(|d| {
!ctx.config.disabled.contains(d.code.as_str())
&& !(ctx.config.disable_experimental && d.experimental)
});
res
}
fn fix(id: &'static str, label: &str, source_change: SourceChange, target: TextRange) -> Assist {
let mut res = unresolved_fix(id, label, target);
res.source_change = Some(source_change);
res
}
fn unresolved_fix(id: &'static str, label: &str, target: TextRange) -> Assist {
assert!(!id.contains(' '));
Assist {
id: AssistId(id, AssistKind::QuickFix),
label: Label::new(label.to_string()),
group: None,
target,
source_change: None,
}
}