src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/unresolved_proc_macro.rs

   1 use hir::db::DefDatabase;
   2
   3 use crate::{Diagnostic, DiagnosticsContext, Severity};
   4
   5 // Diagnostic: unresolved-proc-macro
   6 //
   7 // This diagnostic is shown when a procedural macro can not be found. This usually means that
   8 // procedural macro support is simply disabled (and hence is only a weak hint instead of an error),
   9 // but can also indicate project setup problems.
  10 //
  11 // If you are seeing a lot of "proc macro not expanded" warnings, you can add this option to the
  12 // `rust-analyzer.diagnostics.disabled` list to prevent them from showing. Alternatively you can
  13 // enable support for procedural macros (see `rust-analyzer.procMacro.attributes.enable`).
  14 pub(crate) fn unresolved_proc_macro(
  15     ctx: &DiagnosticsContext<'_>,
  16     d: &hir::UnresolvedProcMacro,
  17     proc_macros_enabled: bool,
  18     proc_attr_macros_enabled: bool,
  19 ) -> Diagnostic {
  20     // Use more accurate position if available.
  21     let display_range = ctx.resolve_precise_location(&d.node, d.precise_location);
  22
  23     let config_enabled = match d.kind {
  24         hir::MacroKind::Attr => proc_macros_enabled && proc_attr_macros_enabled,
  25         _ => proc_macros_enabled,
  26     };
  27
  28     let message = match &d.macro_name {
  29         Some(name) => format!("proc macro `{name}` not expanded"),
  30         None => "proc macro not expanded".to_string(),
  31     };
  32     let severity = if config_enabled { Severity::Error } else { Severity::WeakWarning };
  33     let def_map = ctx.sema.db.crate_def_map(d.krate);
  34     let message = format!(
  35         "{message}: {}",
  36         if config_enabled {
  37             match def_map.proc_macro_loading_error() {
  38                 Some(e) => e,
  39                 None => "proc macro not found in the built dylib",
  40             }
  41         } else {
  42             match d.kind {
  43                 hir::MacroKind::Attr if proc_macros_enabled => {
  44                     "attribute macro expansion is disabled"
  45                 }
  46                 _ => "proc-macro expansion is disabled",
  47             }
  48         },
  49     );
  50
  51     Diagnostic::new("unresolved-proc-macro", message, display_range).severity(severity)
  52 }