Merge #403

403: initial support for macros r=matklad a=matklad

I'll write a more comprehensive description when this is closer to being done. Basically this investigates one question: "how do we represent code which is a result of a macro call". This is an interesting question: currently everything is `FileId` based, but macro expansion does not have a file!

Co-authored-by: Aleksey Kladov <[email protected]>

1 files changed, 30 insertions, 0 deletions

diff --git a/crates/ra_syntax/src/ast.rs b/crates/ra_syntax/src/ast.rs
index 8fb6b6408..3e948800e 100644
--- a/crates/ra_syntax/src/ast.rs
+++ b/crates/ra_syntax/src/ast.rs
@@ -48,10 +48,40 @@ pub trait FnDefOwner<'a>: AstNode<'a> {
     }
 }
 
+// ModuleItem
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ItemOrMacro<'a> {
+    Item(ModuleItem<'a>),
+    Macro(MacroCall<'a>),
+}
+
+impl<'a> AstNode<'a> for ItemOrMacro<'a> {
+    fn cast(syntax: SyntaxNodeRef<'a>) -> Option<Self> {
+        let res = if let Some(item) = ModuleItem::cast(syntax) {
+            ItemOrMacro::Item(item)
+        } else if let Some(macro_call) = MacroCall::cast(syntax) {
+            ItemOrMacro::Macro(macro_call)
+        } else {
+            return None;
+        };
+        Some(res)
+    }
+    fn syntax(self) -> SyntaxNodeRef<'a> {
+        match self {
+            ItemOrMacro::Item(it) => it.syntax(),
+            ItemOrMacro::Macro(it) => it.syntax(),
+        }
+    }
+}
+
 pub trait ModuleItemOwner<'a>: AstNode<'a> {
     fn items(self) -> AstChildren<'a, ModuleItem<'a>> {
         children(self)
     }
+
+    fn items_with_macros(self) -> AstChildren<'a, ItemOrMacro<'a>> {
+        children(self)
+    }
 }
 
 pub trait TypeParamsOwner<'a>: AstNode<'a> {