rust-analyzer

diff --git a/crates/hir/src/diagnostics.rs b/crates/hir/src/diagnostics.rs
index 0f1963e831..5c4104baae 100644
--- a/crates/hir/src/diagnostics.rs
+++ b/crates/hir/src/diagnostics.rs

@@ -32,6 +32,7 @@ diagnostics![

BreakOutsideOfLoop,

InactiveCode,

IncorrectCase,

+ InvalidDeriveTarget,

MacroError,

MismatchedArgCount,

MissingFields,

@@ -99,6 +100,11 @@ pub struct UnimplementedBuiltinMacro {

}

#[derive(Debug)]

+pub struct InvalidDeriveTarget {

+ pub node: InFile<SyntaxNodePtr>,

+#[derive(Debug)]

pub struct NoSuchField {

pub field: InFile<AstPtr<ast::RecordExprField>>,

}

diff --git a/crates/hir/src/lib.rs b/crates/hir/src/lib.rs
index 4fdcb88bbf..cca9b08f5b 100644
--- a/crates/hir/src/lib.rs
+++ b/crates/hir/src/lib.rs

@@ -83,10 +83,10 @@ pub use crate::{

attrs::{HasAttrs, Namespace},

diagnostics::{

AddReferenceHere, AnyDiagnostic, BreakOutsideOfLoop, InactiveCode, IncorrectCase,

- MacroError, MismatchedArgCount, MissingFields, MissingMatchArms, MissingOkOrSomeInTailExpr,

- MissingUnsafe, NoSuchField, RemoveThisSemicolon, ReplaceFilterMapNextWithFindMap,

- UnimplementedBuiltinMacro, UnresolvedExternCrate, UnresolvedImport, UnresolvedMacroCall,

- UnresolvedModule, UnresolvedProcMacro,

+ InvalidDeriveTarget, MacroError, MismatchedArgCount, MissingFields, MissingMatchArms,

+ MissingOkOrSomeInTailExpr, MissingUnsafe, NoSuchField, RemoveThisSemicolon,

+ ReplaceFilterMapNextWithFindMap, UnimplementedBuiltinMacro, UnresolvedExternCrate,

+ UnresolvedImport, UnresolvedMacroCall, UnresolvedModule, UnresolvedProcMacro,

has_source::HasSource,

semantics::{PathResolution, Semantics, SemanticsScope, TypeInfo},

@@ -654,6 +654,21 @@ impl Module {

.into(),

);

}

+ DefDiagnosticKind::InvalidDeriveTarget { ast, id } => {

+ let node = ast.to_node(db.upcast());

+ let derive = node.attrs().nth(*id as usize);

+ match derive {

+ Some(derive) => {

+ acc.push(

+ InvalidDeriveTarget {

+ node: ast.with_value(SyntaxNodePtr::from(AstPtr::new(&derive))),

+ }

+ .into(),

+ );

+ }

+ None => stdx::never!("derive diagnostic on item without derive attribute"),

+ }

}

for decl in self.declarations(db) {

diff --git a/crates/hir_def/src/nameres/collector.rs b/crates/hir_def/src/nameres/collector.rs
index 964af8a8a4..343e189046 100644
--- a/crates/hir_def/src/nameres/collector.rs
+++ b/crates/hir_def/src/nameres/collector.rs

@@ -1055,13 +1055,10 @@ impl DefCollector<'_> {

&resolver,

&mut |_err| (),

);

- match call_id {

- Ok(Ok(call_id)) => {

- resolved.push((directive.module_id, call_id, directive.depth));

- res = ReachedFixedPoint::No;

- return false;

- }

- Err(UnresolvedMacro { .. }) | Ok(Err(_)) => {}

+ if let Ok(Ok(call_id)) = call_id {

+ resolved.push((directive.module_id, call_id, directive.depth));

+ res = ReachedFixedPoint::No;

+ return false;

}

MacroDirectiveKind::Derive { ast_id, derive_attr } => {

@@ -1072,19 +1069,16 @@ impl DefCollector<'_> {

self.def_map.krate,

&resolver,

);

- match call_id {

- Ok(call_id) => {

- self.def_map.modules[directive.module_id].scope.add_derive_macro_invoc(

- ast_id.ast_id,

- call_id,

- *derive_attr,

- );

+ if let Ok(call_id) = call_id {

+ self.def_map.modules[directive.module_id].scope.add_derive_macro_invoc(

+ ast_id.ast_id,

+ call_id,

+ *derive_attr,

+ );

- resolved.push((directive.module_id, call_id, directive.depth));

- res = ReachedFixedPoint::No;

- return false;

- }

- Err(UnresolvedMacro { .. }) => {}

+ resolved.push((directive.module_id, call_id, directive.depth));

+ res = ReachedFixedPoint::No;

+ return false;

}

MacroDirectiveKind::Attr { ast_id, mod_item, attr } => {

@@ -1125,7 +1119,6 @@ impl DefCollector<'_> {

if expander.is_derive()

) {

// Resolved to `#[derive]`

- let file_id = ast_id.ast_id.file_id;

let item_tree = self.db.file_item_tree(file_id);

let ast_id: FileAstId<ast::Item> = match *mod_item {

@@ -1133,8 +1126,12 @@ impl DefCollector<'_> {

ModItem::Union(it) => item_tree[it].ast_id.upcast(),

ModItem::Enum(it) => item_tree[it].ast_id.upcast(),

_ => {

- // Cannot use derive on this item.

- // FIXME: diagnose

+ let diag = DefDiagnostic::invalid_derive_target(

+ directive.module_id,

+ ast_id.ast_id,

+ attr.id,

+ );

+ self.def_map.diagnostics.push(diag);

res = ReachedFixedPoint::No;

return false;

}

@@ -1194,7 +1191,6 @@ impl DefCollector<'_> {

);

- let file_id = ast_id.ast_id.file_id;

let item_tree = self.db.file_item_tree(file_id);

return recollect_without(self, &item_tree);

}

diff --git a/crates/hir_def/src/nameres/diagnostics.rs b/crates/hir_def/src/nameres/diagnostics.rs
index 95061f6015..1eb3844731 100644
--- a/crates/hir_def/src/nameres/diagnostics.rs
+++ b/crates/hir_def/src/nameres/diagnostics.rs

@@ -6,6 +6,7 @@ use la_arena::Idx;

use syntax::ast;

use crate::{

+ attr::AttrId,

item_tree::{self, ItemTreeId},

nameres::LocalModuleId,

path::ModPath,

@@ -29,6 +30,8 @@ pub enum DefDiagnosticKind {

MacroError { ast: MacroCallKind, message: String },

UnimplementedBuiltinMacro { ast: AstId<ast::Macro> },

+ InvalidDeriveTarget { ast: AstId<ast::Item>, id: u32 },

}

#[derive(Debug, PartialEq, Eq)]

@@ -102,4 +105,15 @@ impl DefDiagnostic {

) -> Self {

Self { in_module: container, kind: DefDiagnosticKind::UnimplementedBuiltinMacro { ast } }

}

+ pub(super) fn invalid_derive_target(

+ container: LocalModuleId,

+ ast: AstId<ast::Item>,

+ id: AttrId,

+ ) -> Self {

+ Self {

+ in_module: container,

+ kind: DefDiagnosticKind::InvalidDeriveTarget { ast, id: id.ast_index },

+ }

}

diff --git a/crates/ide_diagnostics/src/handlers/invalid_derive_target.rs b/crates/ide_diagnostics/src/handlers/invalid_derive_target.rs
new file mode 100644
index 0000000000..556d2dc0cb
--- /dev/null
+++ b/crates/ide_diagnostics/src/handlers/invalid_derive_target.rs

@@ -0,0 +1,39 @@

+use crate::{Diagnostic, DiagnosticsContext, Severity};

+// Diagnostic: invalid-derive-target

+//

+// This diagnostic is shown when the derive attribute is used on an item other than a `struct`,

+// `enum` or `union`.

+pub(crate) fn invalid_derive_target(

+ ctx: &DiagnosticsContext<'_>,

+ d: &hir::InvalidDeriveTarget,

+) -> Diagnostic {

+ // Use more accurate position if available.

+ let display_range = ctx.sema.diagnostics_display_range(d.node.clone()).range;

+ Diagnostic::new(

+ "invalid-derive-target",

+ "`derive` may only be applied to `struct`s, `enum`s and `union`s",

+ display_range,

+ )

+ .severity(Severity::Error)

+#[cfg(test)]

+mod tests {

+ use crate::tests::check_diagnostics;

+ #[test]

+ fn fails_on_function() {

+ check_diagnostics(

+ r#"

+//- minicore:derive

+mod __ {

+ #[derive()]

+ //^^^^^^^^^^^ error: `derive` may only be applied to `struct`s, `enum`s and `union`s

+ fn main() {}

+ "#,

+ );

+ }

diff --git a/crates/ide_diagnostics/src/lib.rs b/crates/ide_diagnostics/src/lib.rs
index 2f53b647b1..5070f24003 100644
--- a/crates/ide_diagnostics/src/lib.rs
+++ b/crates/ide_diagnostics/src/lib.rs

@@ -28,6 +28,7 @@ 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 mismatched_arg_count;

pub(crate) mod missing_fields;

@@ -195,6 +196,7 @@ pub fn diagnostics(

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,