1 files changed, 180 insertions, 0 deletions

diff --git a/crates/libanalysis/src/module_map_db/mod.rs b/crates/libanalysis/src/module_map_db/mod.rs
new file mode 100644
index 000000000..777f7a38a
--- /dev/null
+++ b/crates/libanalysis/src/module_map_db/mod.rs
@@ -0,0 +1,180 @@
+mod descr;
+
+use std::sync::Arc;
+use {
+    FileId,
+    db::{
+        BoxedQuery, Query, QueryCtx
+    },
+    module_map::resolve_submodule,
+};
+
+pub(crate) fn queries(acc: &mut Vec<BoxedQuery>) {
+    acc.push(MODULE_DESCR.into());
+    acc.push(RESOLVE_SUBMODULE.into());
+    acc.push(PARENT_MODULE.into());
+}
+
+impl<'a> QueryCtx<'a> {
+    fn module_descr(&self, file_id: FileId) -> Arc<descr::ModuleDescr> {
+        self.get(MODULE_DESCR, file_id)
+    }
+    fn resolve_submodule(&self, file_id: FileId, submod: descr::Submodule) -> Arc<Vec<FileId>> {
+        self.get(RESOLVE_SUBMODULE, (file_id, submod))
+    }
+}
+
+pub(crate) const MODULE_DESCR: Query<FileId, descr::ModuleDescr> = Query {
+    id: 30,
+    f: |ctx, &file_id| {
+        let file = ctx.file_syntax(file_id);
+        descr::ModuleDescr::new(file.ast())
+    }
+};
+
+pub(crate) const RESOLVE_SUBMODULE: Query<(FileId, descr::Submodule), Vec<FileId>> = Query {
+    id: 31,
+    f: |ctx, params| {
+        let files = ctx.file_set();
+        resolve_submodule(params.0, &params.1.name, &files.1).0
+    }
+};
+
+pub(crate) const PARENT_MODULE: Query<FileId, Vec<FileId>> = Query {
+    id: 40,
+    f: |ctx, file_id| {
+        let files = ctx.file_set();
+        let res = files.0.iter()
+            .map(|&parent_id| (parent_id, ctx.module_descr(parent_id)))
+            .filter(|(parent_id, descr)| {
+                descr.submodules.iter()
+                    .any(|subm| {
+                        ctx.resolve_submodule(*parent_id, subm.clone())
+                            .iter()
+                            .any(|it| it == file_id)
+                    })
+            })
+            .map(|(id, _)| id)
+            .collect();
+        res
+    }
+};
+
+#[cfg(test)]
+mod tests {
+    use std::collections::HashMap;
+    use im;
+    use relative_path::{RelativePath, RelativePathBuf};
+    use {
+        db::{Query, Db, State},
+        imp::FileResolverImp,
+        FileId, FileResolver,
+    };
+    use super::*;
+
+    #[derive(Debug)]
+    struct FileMap(im::HashMap<FileId, RelativePathBuf>);
+
+    impl FileResolver for FileMap {
+        fn file_stem(&self, file_id: FileId) -> String {
+            self.0[&file_id].file_stem().unwrap().to_string()
+        }
+        fn resolve(&self, file_id: FileId, rel: &RelativePath) -> Option<FileId> {
+            let path = self.0[&file_id].join(rel).normalize();
+            self.0.iter()
+                .filter_map(|&(id, ref p)| Some(id).filter(|_| p == &path))
+                .next()
+        }
+    }
+
+    struct Fixture {
+        next_file_id: u32,
+        fm: im::HashMap<FileId, RelativePathBuf>,
+        db: Db,
+    }
+
+    impl Fixture {
+        fn new() -> Fixture {
+            Fixture {
+                next_file_id: 1,
+                fm: im::HashMap::new(),
+                db: Db::new(State::default()),
+            }
+        }
+        fn add_file(&mut self, path: &str, text: &str) -> FileId {
+            assert!(path.starts_with("/"));
+            let file_id = FileId(self.next_file_id);
+            self.next_file_id += 1;
+            self.fm.insert(file_id, RelativePathBuf::from(&path[1..]));
+            let mut new_state = self.db.state().clone();
+            new_state.file_map.insert(file_id, text.to_string().into_boxed_str().into());
+            new_state.resolver = FileResolverImp::new(
+                Arc::new(FileMap(self.fm.clone()))
+            );
+            self.db = self.db.with_state(new_state, &[file_id], true);
+            file_id
+        }
+        fn remove_file(&mut self, file_id: FileId) {
+            self.fm.remove(&file_id);
+            let mut new_state = self.db.state().clone();
+            new_state.file_map.remove(&file_id);
+            new_state.resolver = FileResolverImp::new(
+                Arc::new(FileMap(self.fm.clone()))
+            );
+            self.db = self.db.with_state(new_state, &[file_id], true);
+        }
+        fn change_file(&mut self, file_id: FileId, new_text: &str) {
+            let mut new_state = self.db.state().clone();
+            new_state.file_map.insert(file_id, new_text.to_string().into_boxed_str().into());
+            self.db = self.db.with_state(new_state, &[file_id], false);
+        }
+        fn check_parent_modules(
+            &self,
+            file_id: FileId,
+            expected: &[FileId],
+            queries: &[(u16, u64)]
+        ) {
+            let (actual, events) = self.db.get(PARENT_MODULE, file_id);
+            assert_eq!(actual.as_slice(), expected);
+            let mut counts = HashMap::new();
+            events.into_iter()
+               .for_each(|event| *counts.entry(event).or_insert(0) += 1);
+            for &(query_id, expected_count) in queries.iter() {
+                let actual_count = *counts.get(&query_id).unwrap_or(&0);
+                assert_eq!(
+                    actual_count,
+                    expected_count,
+                    "counts for {} differ",
+                    query_id,
+                )
+            }
+
+        }
+    }
+
+    #[test]
+    fn test_parent_module() {
+        let mut f = Fixture::new();
+        let foo = f.add_file("/foo.rs", "");
+        f.check_parent_modules(foo, &[], &[(MODULE_DESCR.id, 1)]);
+
+        let lib = f.add_file("/lib.rs", "mod foo;");
+        f.check_parent_modules(foo, &[lib], &[(MODULE_DESCR.id, 1)]);
+        f.check_parent_modules(foo, &[lib], &[(MODULE_DESCR.id, 0)]);
+
+        f.change_file(lib, "");
+        f.check_parent_modules(foo, &[], &[(MODULE_DESCR.id, 1)]);
+
+        f.change_file(lib, "mod foo;");
+        f.check_parent_modules(foo, &[lib], &[(MODULE_DESCR.id, 1)]);
+
+        f.change_file(lib, "mod bar;");
+        f.check_parent_modules(foo, &[], &[(MODULE_DESCR.id, 1)]);
+
+        f.change_file(lib, "mod foo;");
+        f.check_parent_modules(foo, &[lib], &[(MODULE_DESCR.id, 1)]);
+
+        f.remove_file(lib);
+        f.check_parent_modules(foo, &[], &[(MODULE_DESCR.id, 0)]);
+    }
+}