fix: Ignore some warnings if they originate from within macro expansions

crates/ide-diagnostics/src/handlers/mutability_errors.rs

@@ -7,7 +7,11 @@ use crate::{fix, Diagnostic, DiagnosticCode, DiagnosticsContext};
 // Diagnostic: need-mut
 //
 // This diagnostic is triggered on mutating an immutable variable.
-pub(crate) fn need_mut(ctx: &DiagnosticsContext<'_>, d: &hir::NeedMut) -> Diagnostic {
+pub(crate) fn need_mut(ctx: &DiagnosticsContext<'_>, d: &hir::NeedMut) -> Option<Diagnostic> {
+    if d.span.file_id.macro_file().is_some() {
+        // FIXME: Our infra can't handle allow from within macro expansions rn
+        return None;
+    }
     let fixes = (|| {
         if d.local.is_ref(ctx.sema.db) {
             // There is no simple way to add `mut` to `ref x` and `ref mut x`
@@ -29,17 +33,19 @@ pub(crate) fn need_mut(ctx: &DiagnosticsContext<'_>, d: &hir::NeedMut) -> Diagno
             use_range,
         )])
     })();
-    Diagnostic::new_with_syntax_node_ptr(
+    Some(
-        ctx,
+        Diagnostic::new_with_syntax_node_ptr(
-        // FIXME: `E0384` is not the only error that this diagnostic handles
+            ctx,
-        DiagnosticCode::RustcHardError("E0384"),
+            // FIXME: `E0384` is not the only error that this diagnostic handles
-        format!(
+            DiagnosticCode::RustcHardError("E0384"),
-            "cannot mutate immutable variable `{}`",
+            format!(
-            d.local.name(ctx.sema.db).display(ctx.sema.db)
+                "cannot mutate immutable variable `{}`",
-        ),
+                d.local.name(ctx.sema.db).display(ctx.sema.db)
-        d.span,
+            ),
+            d.span,
+        )
+        .with_fixes(fixes),
     )
-    .with_fixes(fixes)
 }
 
 // Diagnostic: unused-mut

crates/ide-diagnostics/src/handlers/remove_trailing_return.rs

@@ -12,7 +12,12 @@ use crate::{adjusted_display_range, fix, Diagnostic, DiagnosticCode, Diagnostics
 pub(crate) fn remove_trailing_return(
     ctx: &DiagnosticsContext<'_>,
     d: &RemoveTrailingReturn,
-) -> Diagnostic {
+) -> Option<Diagnostic> {
+    if d.return_expr.file_id.macro_file().is_some() {
+        // FIXME: Our infra can't handle allow from within macro expansions rn
+        return None;
+    }
+
     let display_range = adjusted_display_range(ctx, d.return_expr, &|return_expr| {
         return_expr
             .syntax()
@@ -20,12 +25,14 @@ pub(crate) fn remove_trailing_return(
             .and_then(ast::ExprStmt::cast)
             .map(|stmt| stmt.syntax().text_range())
     });
-    Diagnostic::new(
+    Some(
-        DiagnosticCode::Clippy("needless_return"),
+        Diagnostic::new(
-        "replace return <expr>; with <expr>",
+            DiagnosticCode::Clippy("needless_return"),
-        display_range,
+            "replace return <expr>; with <expr>",
+            display_range,
+        )
+        .with_fixes(fixes(ctx, d)),
     )
-    .with_fixes(fixes(ctx, d))
 }
 
 fn fixes(ctx: &DiagnosticsContext<'_>, d: &RemoveTrailingReturn) -> Option<Vec<Assist>> {

crates/ide-diagnostics/src/handlers/remove_unnecessary_else.rs

@@ -21,17 +21,24 @@ use crate::{
 pub(crate) fn remove_unnecessary_else(
     ctx: &DiagnosticsContext<'_>,
     d: &RemoveUnnecessaryElse,
-) -> Diagnostic {
+) -> Option<Diagnostic> {
+    if d.if_expr.file_id.macro_file().is_some() {
+        // FIXME: Our infra can't handle allow from within macro expansions rn
+        return None;
+    }
+
     let display_range = adjusted_display_range(ctx, d.if_expr, &|if_expr| {
         if_expr.else_token().as_ref().map(SyntaxToken::text_range)
     });
-    Diagnostic::new(
+    Some(
-        DiagnosticCode::Ra("remove-unnecessary-else", Severity::WeakWarning),
+        Diagnostic::new(
-        "remove unnecessary else block",
+            DiagnosticCode::Ra("remove-unnecessary-else", Severity::WeakWarning),
-        display_range,
+            "remove unnecessary else block",
+            display_range,
+        )
+        .experimental()
+        .with_fixes(fixes(ctx, d)),
     )
-    .experimental()
-    .with_fixes(fixes(ctx, d))
 }
 
 fn fixes(ctx: &DiagnosticsContext<'_>, d: &RemoveUnnecessaryElse) -> Option<Vec<Assist>> {

crates/ide-diagnostics/src/handlers/unused_variables.rs

@@ -14,18 +14,24 @@ use crate::{Diagnostic, DiagnosticCode, DiagnosticsContext};
 pub(crate) fn unused_variables(
     ctx: &DiagnosticsContext<'_>,
     d: &hir::UnusedVariable,
-) -> Diagnostic {
+) -> Option<Diagnostic> {
     let ast = d.local.primary_source(ctx.sema.db).syntax_ptr();
+    if ast.file_id.macro_file().is_some() {
+        // FIXME: Our infra can't handle allow from within macro expansions rn
+        return None;
+    }
     let diagnostic_range = ctx.sema.diagnostics_display_range(ast);
     let var_name = d.local.primary_source(ctx.sema.db).syntax().to_string();
-    Diagnostic::new_with_syntax_node_ptr(
+    Some(
-        ctx,
+        Diagnostic::new_with_syntax_node_ptr(
-        DiagnosticCode::RustcLint("unused_variables"),
+            ctx,
-        "unused variable",
+            DiagnosticCode::RustcLint("unused_variables"),
-        ast,
+            "unused variable",
+            ast,
+        )
+        .with_fixes(fixes(&var_name, diagnostic_range, ast.file_id.is_macro()))
+        .experimental(),
     )
-    .with_fixes(fixes(&var_name, diagnostic_range, ast.file_id.is_macro()))
-    .experimental()
 }
 
 fn fixes(var_name: &String, diagnostic_range: FileRange, is_in_marco: bool) -> Option<Vec<Assist>> {
@@ -47,7 +53,7 @@ fn fixes(var_name: &String, diagnostic_range: FileRange, is_in_marco: bool) -> O
 
 #[cfg(test)]
 mod tests {
-    use crate::tests::{check_diagnostics, check_fix, check_no_fix};
+    use crate::tests::{check_diagnostics, check_fix};
 
     #[test]
     fn unused_variables_simple() {
@@ -193,7 +199,7 @@ fn main() {
 
     #[test]
     fn no_fix_for_marco() {
-        check_no_fix(
+        check_diagnostics(
             r#"
 macro_rules! my_macro {
     () => {
@@ -202,7 +208,7 @@ macro_rules! my_macro {
 }
 
 fn main() {
-    $0my_macro!();
+    my_macro!();
 }
 "#,
         );

crates/ide-diagnostics/src/lib.rs

@@ -330,7 +330,6 @@ pub fn diagnostics(
     }
 
     for diag in diags {
-        #[rustfmt::skip]
         let d = match diag {
             AnyDiagnostic::ExpectedFunction(d) => handlers::expected_function::expected_function(&ctx, &d),
             AnyDiagnostic::InactiveCode(d) => match handlers::inactive_code::inactive_code(&ctx, &d) {
@@ -361,7 +360,10 @@ pub fn diagnostics(
             AnyDiagnostic::MissingMatchArms(d) => handlers::missing_match_arms::missing_match_arms(&ctx, &d),
             AnyDiagnostic::MissingUnsafe(d) => handlers::missing_unsafe::missing_unsafe(&ctx, &d),
             AnyDiagnostic::MovedOutOfRef(d) => handlers::moved_out_of_ref::moved_out_of_ref(&ctx, &d),
-            AnyDiagnostic::NeedMut(d) => handlers::mutability_errors::need_mut(&ctx, &d),
+            AnyDiagnostic::NeedMut(d) => match handlers::mutability_errors::need_mut(&ctx, &d) {
+                Some(it) => it,
+                None => continue,
+            },
             AnyDiagnostic::NonExhaustiveLet(d) => handlers::non_exhaustive_let::non_exhaustive_let(&ctx, &d),
             AnyDiagnostic::NoSuchField(d) => handlers::no_such_field::no_such_field(&ctx, &d),
             AnyDiagnostic::PrivateAssocItem(d) => handlers::private_assoc_item::private_assoc_item(&ctx, &d),
@@ -386,11 +388,20 @@ pub fn diagnostics(
             AnyDiagnostic::UnresolvedModule(d) => handlers::unresolved_module::unresolved_module(&ctx, &d),
             AnyDiagnostic::UnresolvedProcMacro(d) => handlers::unresolved_proc_macro::unresolved_proc_macro(&ctx, &d, config.proc_macros_enabled, config.proc_attr_macros_enabled),
             AnyDiagnostic::UnusedMut(d) => handlers::mutability_errors::unused_mut(&ctx, &d),
-            AnyDiagnostic::UnusedVariable(d) => handlers::unused_variables::unused_variables(&ctx, &d),
+            AnyDiagnostic::UnusedVariable(d) => match handlers::unused_variables::unused_variables(&ctx, &d) {
+                Some(it) => it,
+                None => continue,
+            },
             AnyDiagnostic::BreakOutsideOfLoop(d) => handlers::break_outside_of_loop::break_outside_of_loop(&ctx, &d),
             AnyDiagnostic::MismatchedTupleStructPatArgCount(d) => handlers::mismatched_arg_count::mismatched_tuple_struct_pat_arg_count(&ctx, &d),
-            AnyDiagnostic::RemoveTrailingReturn(d) => handlers::remove_trailing_return::remove_trailing_return(&ctx, &d),
+            AnyDiagnostic::RemoveTrailingReturn(d) => match handlers::remove_trailing_return::remove_trailing_return(&ctx, &d) {
-            AnyDiagnostic::RemoveUnnecessaryElse(d) => handlers::remove_unnecessary_else::remove_unnecessary_else(&ctx, &d),
+                Some(it) => it,
+                None => continue,
+            },
+            AnyDiagnostic::RemoveUnnecessaryElse(d) => match handlers::remove_unnecessary_else::remove_unnecessary_else(&ctx, &d) {
+                Some(it) => it,
+                None => continue,
+            },
         };
         res.push(d)
     }