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]>

7 files changed, 46 insertions, 92 deletions

diff --git a/crates/ra_analysis/src/completion/complete_scope.rs b/crates/ra_analysis/src/completion/complete_scope.rs
index daf666505..4dead3689 100644
--- a/crates/ra_analysis/src/completion/complete_scope.rs
+++ b/crates/ra_analysis/src/completion/complete_scope.rs
@@ -27,7 +27,7 @@ pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) ->
             match res.import {
                 None => true,
                 Some(import) => {
-                    let range = import.range(ctx.db, module.source().file_id());
+                    let range = import.range(ctx.db, module.file_id());
                     !range.is_subrange(&ctx.leaf.range())
                 }
             }
diff --git a/crates/ra_analysis/src/db.rs b/crates/ra_analysis/src/db.rs
index b072a5eba..d7740f0c4 100644
--- a/crates/ra_analysis/src/db.rs
+++ b/crates/ra_analysis/src/db.rs
@@ -1,7 +1,6 @@
 use std::{fmt, sync::Arc};
 use salsa::{self, Database};
 use ra_db::{LocationIntener, BaseDatabase};
-use hir::{self, DefId, DefLoc};
 
 use crate::{
     symbol_index,
@@ -15,7 +14,8 @@ pub(crate) struct RootDatabase {
 
 #[derive(Default)]
 struct IdMaps {
-    defs: LocationIntener<DefLoc, DefId>,
+    defs: LocationIntener<hir::DefLoc, hir::DefId>,
+    macros: LocationIntener<hir::MacroCallLoc, hir::MacroCallId>,
 }
 
 impl fmt::Debug for IdMaps {
@@ -59,12 +59,18 @@ impl salsa::ParallelDatabase for RootDatabase {
 
 impl BaseDatabase for RootDatabase {}
 
-impl AsRef<LocationIntener<DefLoc, DefId>> for RootDatabase {
-    fn as_ref(&self) -> &LocationIntener<DefLoc, DefId> {
+impl AsRef<LocationIntener<hir::DefLoc, hir::DefId>> for RootDatabase {
+    fn as_ref(&self) -> &LocationIntener<hir::DefLoc, hir::DefId> {
         &self.id_maps.defs
     }
 }
 
+impl AsRef<LocationIntener<hir::MacroCallLoc, hir::MacroCallId>> for RootDatabase {
+    fn as_ref(&self) -> &LocationIntener<hir::MacroCallLoc, hir::MacroCallId> {
+        &self.id_maps.macros
+    }
+}
+
 salsa::database_storage! {
     pub(crate) struct RootDatabaseStorage for RootDatabase {
         impl ra_db::FilesDatabase {
@@ -85,6 +91,8 @@ salsa::database_storage! {
             fn library_symbols() for symbol_index::LibrarySymbolsQuery;
         }
         impl hir::db::HirDatabase {
+            fn hir_source_file() for hir::db::HirSourceFileQuery;
+            fn expand_macro_invocation() for hir::db::ExpandMacroCallQuery;
             fn module_tree() for hir::db::ModuleTreeQuery;
             fn fn_scopes() for hir::db::FnScopesQuery;
             fn file_items() for hir::db::SourceFileItemsQuery;
diff --git a/crates/ra_analysis/src/extend_selection.rs b/crates/ra_analysis/src/extend_selection.rs
index 805e9059e..f1b77f981 100644
--- a/crates/ra_analysis/src/extend_selection.rs
+++ b/crates/ra_analysis/src/extend_selection.rs
@@ -18,15 +18,15 @@ pub(crate) fn extend_selection(db: &RootDatabase, frange: FileRange) -> TextRang
 }
 
 fn extend_selection_in_macro(
-    db: &RootDatabase,
+    _db: &RootDatabase,
     source_file: &SourceFileNode,
     frange: FileRange,
 ) -> Option<TextRange> {
     let macro_call = find_macro_call(source_file.syntax(), frange.range)?;
-    let exp = crate::macros::expand(db, frange.file_id, macro_call)?;
-    let dst_range = exp.map_range_forward(frange.range)?;
-    let dst_range = ra_editor::extend_selection(exp.source_file().syntax(), dst_range)?;
-    let src_range = exp.map_range_back(dst_range)?;
+    let (off, exp) = hir::MacroDef::ast_expand(macro_call)?;
+    let dst_range = exp.map_range_forward(frange.range - off)?;
+    let dst_range = ra_editor::extend_selection(exp.syntax().borrowed(), dst_range)?;
+    let src_range = exp.map_range_back(dst_range)? + off;
     Some(src_range)
 }
 
diff --git a/crates/ra_analysis/src/imp.rs b/crates/ra_analysis/src/imp.rs
index 5669aa94d..ec7da437a 100644
--- a/crates/ra_analysis/src/imp.rs
+++ b/crates/ra_analysis/src/imp.rs
@@ -230,7 +230,7 @@ impl AnalysisImpl {
             Some(it) => it,
         };
         let root = descr.crate_root();
-        let file_id = root.source().file_id();
+        let file_id = root.file_id();
 
         let crate_graph = self.db.crate_graph();
         let crate_id = crate_graph.crate_id_for_crate_root(file_id);
@@ -283,7 +283,7 @@ impl AnalysisImpl {
                     if let Some(child_module) =
                         source_binder::module_from_declaration(&*self.db, position.file_id, module)?
                     {
-                        let file_id = child_module.source().file_id();
+                        let file_id = child_module.file_id();
                         let name = match child_module.name() {
                             Some(name) => name.to_string().into(),
                             None => "".into(),
diff --git a/crates/ra_analysis/src/lib.rs b/crates/ra_analysis/src/lib.rs
index e6cfaecc3..08ecb125a 100644
--- a/crates/ra_analysis/src/lib.rs
+++ b/crates/ra_analysis/src/lib.rs
@@ -19,7 +19,6 @@ mod runnables;
 
 mod extend_selection;
 mod syntax_highlighting;
-mod macros;
 
 use std::{fmt, sync::Arc};
 
diff --git a/crates/ra_analysis/src/macros.rs b/crates/ra_analysis/src/macros.rs
deleted file mode 100644
index b9feb7fad..000000000
--- a/crates/ra_analysis/src/macros.rs
+++ /dev/null
@@ -1,75 +0,0 @@
-/// Begining of macro expansion.
-///
-/// This code should be moved out of ra_analysis into hir (?) ideally.
-use ra_syntax::{ast, AstNode, SourceFileNode, TextRange};
-
-use crate::{db::RootDatabase, FileId};
-
-pub(crate) fn expand(
-    _db: &RootDatabase,
-    _file_id: FileId,
-    macro_call: ast::MacroCall,
-) -> Option<MacroExpansion> {
-    let path = macro_call.path()?;
-    if path.qualifier().is_some() {
-        return None;
-    }
-    let name_ref = path.segment()?.name_ref()?;
-    if name_ref.text() != "ctry" {
-        return None;
-    }
-
-    let arg = macro_call.token_tree()?;
-    let text = format!(
-        r"
-        fn dummy() {{
-            match {} {{
-                None => return Ok(None),
-                Some(it) => it,
-            }}
-        }}",
-        arg.syntax().text()
-    );
-    let file = SourceFileNode::parse(&text);
-    let match_expr = file.syntax().descendants().find_map(ast::MatchExpr::cast)?;
-    let match_arg = match_expr.expr()?;
-    let ranges_map = vec![(arg.syntax().range(), match_arg.syntax().range())];
-    let res = MacroExpansion {
-        source_file: file,
-        ranges_map,
-    };
-    Some(res)
-}
-
-pub(crate) struct MacroExpansion {
-    pub(crate) source_file: SourceFileNode,
-    pub(crate) ranges_map: Vec<(TextRange, TextRange)>,
-}
-
-impl MacroExpansion {
-    pub(crate) fn source_file(&self) -> &SourceFileNode {
-        &self.source_file
-    }
-    pub(crate) fn map_range_back(&self, tgt_range: TextRange) -> Option<TextRange> {
-        for (s_range, t_range) in self.ranges_map.iter() {
-            if tgt_range.is_subrange(&t_range) {
-                let tgt_at_zero_range = tgt_range - tgt_range.start();
-                let tgt_range_offset = tgt_range.start() - t_range.start();
-                let src_range = tgt_at_zero_range + tgt_range_offset + s_range.start();
-                return Some(src_range);
-            }
-        }
-        None
-    }
-    pub(crate) fn map_range_forward(&self, src_range: TextRange) -> Option<TextRange> {
-        for (s_range, t_range) in self.ranges_map.iter() {
-            if src_range.is_subrange(&s_range) {
-                let src_at_zero_range = src_range - src_range.start();
-                let src_range_offset = src_range.start() - s_range.start();
-                let src_range = src_at_zero_range + src_range_offset + t_range.start();
-                return Some(src_range);
-            }
-        }
-        None
-    }
-}
diff --git a/crates/ra_analysis/src/syntax_highlighting.rs b/crates/ra_analysis/src/syntax_highlighting.rs
index 7e9139a74..ccea4aee3 100644
--- a/crates/ra_analysis/src/syntax_highlighting.rs
+++ b/crates/ra_analysis/src/syntax_highlighting.rs
@@ -15,13 +15,13 @@ pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Cancelable<Vec<Hi
         .descendants()
         .filter_map(ast::MacroCall::cast)
     {
-        if let Some(exp) = crate::macros::expand(db, file_id, macro_call) {
-            let mapped_ranges = ra_editor::highlight(exp.source_file().syntax())
+        if let Some((off, exp)) = hir::MacroDef::ast_expand(macro_call) {
+            let mapped_ranges = ra_editor::highlight(exp.syntax().borrowed())
                 .into_iter()
                 .filter_map(|r| {
                     let mapped_range = exp.map_range_back(r.range)?;
                     let res = HighlightedRange {
-                        range: mapped_range,
+                        range: mapped_range + off,
                         tag: r.tag,
                     };
                     Some(res)
@@ -44,7 +44,7 @@ mod tests {
             fn main() {
                 ctry!({ let x = 92; x});
             }
-        ",
+            ",
         );
         let highlights = analysis.highlight(file_id).unwrap();
         assert_eq_dbg(
@@ -60,4 +60,26 @@ mod tests {
             &highlights,
         )
     }
+
+    // FIXME: this test is not really necessary: artifact of the inital hacky
+    // macros implementation.
+    #[test]
+    fn highlight_query_group_macro() {
+        let (analysis, file_id) = single_file(
+            "
+            salsa::query_group! {
+                pub trait HirDatabase: SyntaxDatabase {}
+            }
+            ",
+        );
+        let highlights = analysis.highlight(file_id).unwrap();
+        assert_eq_dbg(
+            r#"[HighlightedRange { range: [20; 32), tag: "macro" },
+                HighlightedRange { range: [13; 18), tag: "text" },
+                HighlightedRange { range: [51; 54), tag: "keyword" },
+                HighlightedRange { range: [55; 60), tag: "keyword" },
+                HighlightedRange { range: [61; 72), tag: "function" }]"#,
+            &highlights,
+        )
+    }
 }