Merge #350

350: Super simple macro support r=matklad a=matklad

Super simple support for macros, mostly for figuring out how to fit them into the current architecture. Expansion is hard-coded and string based (mid-term, we should try to copy-paste macro-by-example expander from rustc). 

Ideally, we should handle

* highlighting inside the macro (done)
* extend selection inside the macro 
* completion inside the macro
* indexing structs, produced by the macro

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

1 files changed, 63 insertions, 0 deletions

diff --git a/crates/ra_analysis/src/syntax_highlighting.rs b/crates/ra_analysis/src/syntax_highlighting.rs
new file mode 100644
index 000000000..38219da71
--- /dev/null
+++ b/crates/ra_analysis/src/syntax_highlighting.rs
@@ -0,0 +1,63 @@
+use ra_syntax::{ast, AstNode,};
+use ra_editor::HighlightedRange;
+use ra_db::SyntaxDatabase;
+
+use crate::{
+    db::RootDatabase,
+    FileId, Cancelable,
+};
+
+pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Cancelable<Vec<HighlightedRange>> {
+    let source_file = db.source_file(file_id);
+    let mut res = ra_editor::highlight(&source_file);
+    for macro_call in source_file
+        .syntax()
+        .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())
+                .into_iter()
+                .filter_map(|r| {
+                    let mapped_range = exp.map_range_back(r.range)?;
+                    let res = HighlightedRange {
+                        range: mapped_range,
+                        tag: r.tag,
+                    };
+                    Some(res)
+                });
+            res.extend(mapped_ranges);
+        }
+    }
+    Ok(res)
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::mock_analysis::single_file;
+    use test_utils::assert_eq_dbg;
+
+    #[test]
+    fn highlights_code_inside_macros() {
+        let (analysis, file_id) = single_file(
+            "
+            fn main() {
+                ctry!({ let x = 92; x});
+            }
+        ",
+        );
+        let highlights = analysis.highlight(file_id).unwrap();
+        assert_eq_dbg(
+            r#"[HighlightedRange { range: [13; 15), tag: "keyword" },
+                HighlightedRange { range: [16; 20), tag: "function" },
+                HighlightedRange { range: [41; 46), tag: "macro" },
+                HighlightedRange { range: [49; 52), tag: "keyword" },
+                HighlightedRange { range: [57; 59), tag: "literal" },
+                HighlightedRange { range: [49; 52), tag: "keyword" },
+                HighlightedRange { range: [53; 54), tag: "function" },
+                HighlightedRange { range: [57; 59), tag: "literal" },
+                HighlightedRange { range: [61; 62), tag: "text" }]"#,
+            &highlights,
+        )
+    }
+}