ide: basic salsa setup

Cargo.toml

@@ -38,6 +38,7 @@ drop_bomb = "0.1.5"
 camino = "1.1.9"
 pg_query = "6.1.0"
 rowan = "0.15.15"
+salsa = "0.26.0"
 smol_str = "0.3.2"
 enum-iterator = "2.1.0"
 itertools = "0.14.0"

crates/squawk_server/Cargo.toml

@@ -20,6 +20,7 @@ simplelog.workspace = true
 lsp-server.workspace = true
 lsp-types.workspace = true
 rowan.workspace = true
+salsa.workspace = true
 serde.workspace = true
 serde_json.workspace = true
 squawk-ide.workspace = true

crates/squawk_server/src/db.rs

@@ -0,0 +1,29 @@
+use ::line_index::LineIndex;
+use salsa::Database as Db;
+use salsa::Storage;
+use squawk_syntax::{Parse, SourceFile};
+
+#[salsa::input]
+pub struct File {
+    #[returns(ref)]
+    pub content: String,
+    pub version: i32,
+}
+
+#[salsa::tracked]
+pub fn parse(db: &dyn Db, file: File) -> Parse<SourceFile> {
+    SourceFile::parse(file.content(db))
+}
+
+#[salsa::tracked]
+pub fn line_index(db: &dyn Db, file: File) -> LineIndex {
+    LineIndex::new(file.content(db))
+}
+
+#[salsa::db]
+#[derive(Default)]
+pub struct Database {
+    storage: Storage<Self>,
+}
+
+impl salsa::Database for Database {}