extend selection works with macros

crates/ra_analysis/src/extend_selection.rs

@@ -1,4 +1,8 @@
 use ra_db::SyntaxDatabase;
+use ra_syntax::{
+    SyntaxNodeRef, AstNode,
+    ast, algo::find_covering_node,
+};
 
 use crate::{
     TextRange, FileRange,
@@ -6,6 +10,42 @@ use crate::{
 };
 
 pub(crate) fn extend_selection(db: &RootDatabase, frange: FileRange) -> TextRange {
-    let file = db.source_file(frange.file_id);
-    ra_editor::extend_selection(&file, frange.range).unwrap_or(frange.range)
+    let source_file = db.source_file(frange.file_id);
+    if let Some(macro_call) = find_macro_call(source_file.syntax(), frange.range) {
+        if let Some(exp) = crate::macros::expand(db, frange.file_id, macro_call) {
+            if let Some(dst_range) = exp.map_range_forward(frange.range) {
+                if let Some(dst_range) = ra_editor::extend_selection(exp.source_file(), dst_range) {
+                    if let Some(src_range) = exp.map_range_back(dst_range) {
+                        return src_range;
+                    }
+                }
+            }
+        }
+    }
+    ra_editor::extend_selection(&source_file, frange.range).unwrap_or(frange.range)
+}
+
+fn find_macro_call(node: SyntaxNodeRef, range: TextRange) -> Option<ast::MacroCall> {
+    find_covering_node(node, range)
+        .ancestors()
+        .find_map(ast::MacroCall::cast)
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::mock_analysis::single_file_with_range;
+    use test_utils::assert_eq_dbg;
+
+    #[test]
+    fn extend_selection_inside_macros() {
+        let (analysis, frange) = single_file_with_range(
+            "
+            fn main() {
+                ctry!(foo(|x| <|>x<|>));
+            }
+        ",
+        );
+        let r = analysis.extend_selection(frange);
+        assert_eq_dbg("[51; 56)", &r);
+    }
 }

crates/ra_analysis/src/macros.rs

@@ -61,4 +61,15 @@ impl MacroExpansion {
         }
         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
+    }
 }

crates/ra_analysis/src/mock_analysis.rs

@@ -1,10 +1,10 @@
 use std::sync::Arc;
 
 use relative_path::RelativePathBuf;
-use test_utils::{extract_offset, parse_fixture, CURSOR_MARKER};
+use test_utils::{extract_offset, extract_range, parse_fixture, CURSOR_MARKER};
 use ra_db::mock::FileMap;
 
-use crate::{Analysis, AnalysisChange, AnalysisHost, FileId, FilePosition, SourceRootId};
+use crate::{Analysis, AnalysisChange, AnalysisHost, FileId, FilePosition, FileRange, SourceRootId};
 
 /// Mock analysis is used in test to bootstrap an AnalysisHost/Analysis
 /// from a set of in-memory files.
@@ -66,6 +66,12 @@ impl MockAnalysis {
         self.files.push((path.to_string(), text.to_string()));
         FilePosition { file_id, offset }
     }
+    pub fn add_file_with_range(&mut self, path: &str, text: &str) -> FileRange {
+        let (range, text) = extract_range(text);
+        let file_id = FileId((self.files.len() + 1) as u32);
+        self.files.push((path.to_string(), text.to_string()));
+        FileRange { file_id, range }
+    }
     pub fn id_of(&self, path: &str) -> FileId {
         let (idx, _) = self
             .files
@@ -115,3 +121,10 @@ pub fn single_file_with_position(code: &str) -> (Analysis, FilePosition) {
     let pos = mock.add_file_with_position("/main.rs", code);
     (mock.analysis(), pos)
 }
+
+/// Creates analysis for a single file, returns range marked with a pair of <|>.
+pub fn single_file_with_range(code: &str) -> (Analysis, FileRange) {
+    let mut mock = MockAnalysis::new();
+    let pos = mock.add_file_with_range("/main.rs", code);
+    (mock.analysis(), pos)
+}