2 files changed, 190 insertions, 0 deletions

diff --git a/crates/ra_analysis/src/db/input.rs b/crates/ra_analysis/src/db/input.rs
new file mode 100644
index 000000000..957d082f9
--- /dev/null
+++ b/crates/ra_analysis/src/db/input.rs
@@ -0,0 +1,83 @@
+use std::{
+    sync::Arc,
+    hash::{Hasher, Hash},
+};
+
+use salsa;
+use rustc_hash::FxHashSet;
+
+use crate::{FileId, FileResolverImp, CrateGraph, symbol_index::SymbolIndex};
+
+salsa::query_group! {
+    pub(crate) trait FilesDatabase: salsa::Database {
+        fn file_text(file_id: FileId) -> Arc<String> {
+            type FileTextQuery;
+            storage input;
+        }
+        fn file_source_root(file_id: FileId) -> SourceRootId {
+            type FileSourceRootQuery;
+            storage input;
+        }
+        fn source_root(id: SourceRootId) -> Arc<SourceRoot> {
+            type SourceRootQuery;
+            storage input;
+        }
+        fn libraries() -> Arc<Vec<SourceRootId>> {
+            type LibrarieseQuery;
+            storage input;
+        }
+        fn library_symbols(id: SourceRootId) -> Arc<SymbolIndex> {
+            type LibrarySymbolsQuery;
+            storage input;
+        }
+        fn crate_graph() -> Arc<CrateGraph> {
+            type CrateGraphQuery;
+            storage input;
+        }
+    }
+}
+
+#[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
+pub(crate) struct SourceRootId(pub(crate) u32);
+
+#[derive(Clone, Default, Debug, Eq)]
+pub(crate) struct SourceRoot {
+    pub(crate) file_resolver: FileResolverImp,
+    pub(crate) files: FxHashSet<FileId>,
+}
+
+impl PartialEq for SourceRoot {
+    fn eq(&self, other: &SourceRoot) -> bool {
+        self.file_resolver == other.file_resolver
+    }
+}
+
+impl Hash for SourceRoot {
+    fn hash<H: Hasher>(&self, hasher: &mut H) {
+        self.file_resolver.hash(hasher);
+    }
+}
+
+pub(crate) const WORKSPACE: SourceRootId = SourceRootId(0);
+
+
+#[derive(Default, Debug, Eq)]
+pub(crate) struct FileSet {
+    pub(crate) files: FxHashSet<FileId>,
+    pub(crate) resolver: FileResolverImp,
+}
+
+impl PartialEq for FileSet {
+    fn eq(&self, other: &FileSet) -> bool {
+        self.files == other.files && self.resolver == other.resolver
+    }
+}
+
+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);
+    }
+}
+
diff --git a/crates/ra_analysis/src/db/mod.rs b/crates/ra_analysis/src/db/mod.rs
new file mode 100644
index 000000000..8387118ad
--- /dev/null
+++ b/crates/ra_analysis/src/db/mod.rs
@@ -0,0 +1,107 @@
+pub(crate) mod input;
+
+use std::{
+    fmt,
+    sync::Arc,
+};
+
+use ra_editor::LineIndex;
+use ra_syntax::File;
+use salsa;
+
+use crate::{
+    db,
+    Cancelable, Canceled,
+    descriptors::module::{SubmodulesQuery, ModuleTreeQuery, ModulesDatabase},
+    symbol_index::SymbolIndex,
+    FileId,
+};
+
+#[derive(Default)]
+pub(crate) struct RootDatabase {
+    runtime: salsa::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<RootDatabase> {
+        &self.runtime
+    }
+}
+
+pub(crate) fn check_canceled(db: &impl salsa::Database) -> Cancelable<()> {
+    if db.salsa_runtime().is_current_revision_canceled() {
+        Err(Canceled)
+    } else {
+        Ok(())
+    }
+}
+
+impl salsa::ParallelDatabase for RootDatabase {
+    fn fork(&self) -> Self {
+        RootDatabase {
+            runtime: self.runtime.fork(),
+        }
+    }
+}
+
+impl Clone for RootDatabase {
+    fn clone(&self) -> RootDatabase {
+        salsa::ParallelDatabase::fork(self)
+    }
+}
+
+salsa::database_storage! {
+    pub(crate) struct RootDatabaseStorage for RootDatabase {
+        impl input::FilesDatabase {
+            fn file_text() for input::FileTextQuery;
+            fn file_source_root() for input::FileSourceRootQuery;
+            fn source_root() for input::SourceRootQuery;
+            fn libraries() for input::LibrarieseQuery;
+            fn library_symbols() for input::LibrarySymbolsQuery;
+            fn crate_graph() for input::CrateGraphQuery;
+        }
+        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 SubmodulesQuery;
+        }
+    }
+}
+
+salsa::query_group! {
+    pub(crate) trait SyntaxDatabase: input::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) -> Cancelable<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) -> Cancelable<Arc<SymbolIndex>> {
+    db::check_canceled(db)?;
+    let syntax = db.file_syntax(file_id);
+    Ok(Arc::new(SymbolIndex::for_file(file_id, syntax)))
+}