1 files changed, 90 insertions, 0 deletions

diff --git a/crates/hir_def/src/nameres/diagnostics.rs b/crates/hir_def/src/nameres/diagnostics.rs
new file mode 100644
index 000000000..8f2f0ff9f
--- /dev/null
+++ b/crates/hir_def/src/nameres/diagnostics.rs
@@ -0,0 +1,90 @@
+//! Diagnostics emitted during DefMap construction.
+
+use cfg::{CfgExpr, CfgOptions};
+use hir_expand::MacroCallKind;
+use syntax::ast;
+
+use crate::{nameres::LocalModuleId, path::ModPath, AstId};
+
+#[derive(Debug, PartialEq, Eq)]
+pub enum DefDiagnosticKind {
+    UnresolvedModule { ast: AstId<ast::Module>, candidate: String },
+
+    UnresolvedExternCrate { ast: AstId<ast::ExternCrate> },
+
+    UnresolvedImport { ast: AstId<ast::Use>, index: usize },
+
+    UnconfiguredCode { ast: AstId<ast::Item>, cfg: CfgExpr, opts: CfgOptions },
+
+    UnresolvedProcMacro { ast: MacroCallKind },
+
+    UnresolvedMacroCall { ast: AstId<ast::MacroCall>, path: ModPath },
+
+    MacroError { ast: MacroCallKind, message: String },
+}
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct DefDiagnostic {
+    pub in_module: LocalModuleId,
+    pub kind: DefDiagnosticKind,
+}
+
+impl DefDiagnostic {
+    pub(super) fn unresolved_module(
+        container: LocalModuleId,
+        declaration: AstId<ast::Module>,
+        candidate: String,
+    ) -> Self {
+        Self {
+            in_module: container,
+            kind: DefDiagnosticKind::UnresolvedModule { ast: declaration, candidate },
+        }
+    }
+
+    pub(super) fn unresolved_extern_crate(
+        container: LocalModuleId,
+        declaration: AstId<ast::ExternCrate>,
+    ) -> Self {
+        Self {
+            in_module: container,
+            kind: DefDiagnosticKind::UnresolvedExternCrate { ast: declaration },
+        }
+    }
+
+    pub(super) fn unresolved_import(
+        container: LocalModuleId,
+        ast: AstId<ast::Use>,
+        index: usize,
+    ) -> Self {
+        Self { in_module: container, kind: DefDiagnosticKind::UnresolvedImport { ast, index } }
+    }
+
+    pub(super) fn unconfigured_code(
+        container: LocalModuleId,
+        ast: AstId<ast::Item>,
+        cfg: CfgExpr,
+        opts: CfgOptions,
+    ) -> Self {
+        Self { in_module: container, kind: DefDiagnosticKind::UnconfiguredCode { ast, cfg, opts } }
+    }
+
+    pub(super) fn unresolved_proc_macro(container: LocalModuleId, ast: MacroCallKind) -> Self {
+        Self { in_module: container, kind: DefDiagnosticKind::UnresolvedProcMacro { ast } }
+    }
+
+    pub(super) fn macro_error(
+        container: LocalModuleId,
+        ast: MacroCallKind,
+        message: String,
+    ) -> Self {
+        Self { in_module: container, kind: DefDiagnosticKind::MacroError { ast, message } }
+    }
+
+    pub(super) fn unresolved_macro_call(
+        container: LocalModuleId,
+        ast: AstId<ast::MacroCall>,
+        path: ModPath,
+    ) -> Self {
+        Self { in_module: container, kind: DefDiagnosticKind::UnresolvedMacroCall { ast, path } }
+    }
+}