1 files changed, 103 insertions, 0 deletions

diff --git a/crates/ra_analysis/src/db.rs b/crates/ra_analysis/src/db.rs
new file mode 100644
index 000000000..0773edcc1
--- /dev/null
+++ b/crates/ra_analysis/src/db.rs
@@ -0,0 +1,103 @@
+use std::{
+    fmt,
+    sync::Arc,
+    hash::{Hash, Hasher},
+};
+use salsa;
+use rustc_hash::FxHashSet;
+use ra_syntax::File;
+use ra_editor::{LineIndex};
+use crate::{
+    symbol_index::SymbolIndex,
+    module_map::{ModulesDatabase, ModuleTreeQuery, ModuleDescriptorQuery},
+    FileId, FileResolverImp,
+};
+
+#[derive(Default)]
+pub(crate) struct RootDatabase {
+    runtime: salsa::runtime::Runtime<RootDatabase>,
+}
+
+impl fmt::Debug for RootDatabase {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.write_str("RootDatabase { ... }")
+    }
+}
+
+impl salsa::Database for RootDatabase {
+    fn salsa_runtime(&self) -> &salsa::runtime::Runtime<RootDatabase> {
+        &self.runtime
+    }
+}
+
+salsa::database_storage! {
+    pub(crate) struct RootDatabaseStorage for RootDatabase {
+        impl FilesDatabase {
+            fn file_text() for FileTextQuery;
+            fn file_set() for FileSetQuery;
+        }
+        impl SyntaxDatabase {
+            fn file_syntax() for FileSyntaxQuery;
+            fn file_lines() for FileLinesQuery;
+            fn file_symbols() for FileSymbolsQuery;
+        }
+        impl ModulesDatabase {
+            fn module_tree() for ModuleTreeQuery;
+            fn module_descriptor() for ModuleDescriptorQuery;
+        }
+    }
+}
+
+salsa::query_group! {
+    pub(crate) trait FilesDatabase: salsa::Database {
+        fn file_text(file_id: FileId) -> Arc<String> {
+            type FileTextQuery;
+            storage input;
+        }
+        fn file_set(key: ()) -> Arc<FileSet> {
+            type FileSetQuery;
+            storage input;
+        }
+    }
+}
+
+#[derive(Default, Debug, PartialEq, Eq)]
+pub(crate) struct FileSet {
+    pub(crate) files: FxHashSet<FileId>,
+    pub(crate) resolver: FileResolverImp,
+}
+
+impl Hash for FileSet {
+    fn hash<H: Hasher>(&self, hasher: &mut H) {
+        let mut files = self.files.iter().cloned().collect::<Vec<_>>();
+        files.sort();
+        files.hash(hasher);
+    }
+}
+
+salsa::query_group! {
+    pub(crate) trait SyntaxDatabase: FilesDatabase {
+        fn file_syntax(file_id: FileId) -> File {
+            type FileSyntaxQuery;
+        }
+        fn file_lines(file_id: FileId) -> Arc<LineIndex> {
+            type FileLinesQuery;
+        }
+        fn file_symbols(file_id: FileId) -> Arc<SymbolIndex> {
+            type FileSymbolsQuery;
+        }
+    }
+}
+
+fn file_syntax(db: &impl SyntaxDatabase, file_id: FileId) -> File {
+    let text = db.file_text(file_id);
+    File::parse(&*text)
+}
+fn file_lines(db: &impl SyntaxDatabase, file_id: FileId) -> Arc<LineIndex> {
+    let text = db.file_text(file_id);
+    Arc::new(LineIndex::new(&*text))
+}
+fn file_symbols(db: &impl SyntaxDatabase, file_id: FileId) -> Arc<SymbolIndex> {
+    let syntax = db.file_syntax(file_id);
+    Arc::new(SymbolIndex::for_file(file_id, syntax))
+}