Add buffer integration test

Rearrange channel crate structure
Get channel buffer from database

co-authored-by: Max <max@zed.dev>

crates/collab/src/db/tests.rs

@@ -0,0 +1,143 @@
+mod buffer_tests;
+mod db_tests;
+
+use super::*;
+use gpui::executor::Background;
+use parking_lot::Mutex;
+use sea_orm::ConnectionTrait;
+use sqlx::migrate::MigrateDatabase;
+use std::sync::Arc;
+
+pub struct TestDb {
+    pub db: Option<Arc<Database>>,
+    pub connection: Option<sqlx::AnyConnection>,
+}
+
+impl TestDb {
+    pub fn sqlite(background: Arc<Background>) -> Self {
+        let url = format!("sqlite::memory:");
+        let runtime = tokio::runtime::Builder::new_current_thread()
+            .enable_io()
+            .enable_time()
+            .build()
+            .unwrap();
+
+        let mut db = runtime.block_on(async {
+            let mut options = ConnectOptions::new(url);
+            options.max_connections(5);
+            let db = Database::new(options, Executor::Deterministic(background))
+                .await
+                .unwrap();
+            let sql = include_str!(concat!(
+                env!("CARGO_MANIFEST_DIR"),
+                "/migrations.sqlite/20221109000000_test_schema.sql"
+            ));
+            db.pool
+                .execute(sea_orm::Statement::from_string(
+                    db.pool.get_database_backend(),
+                    sql.into(),
+                ))
+                .await
+                .unwrap();
+            db
+        });
+
+        db.runtime = Some(runtime);
+
+        Self {
+            db: Some(Arc::new(db)),
+            connection: None,
+        }
+    }
+
+    pub fn postgres(background: Arc<Background>) -> Self {
+        static LOCK: Mutex<()> = Mutex::new(());
+
+        let _guard = LOCK.lock();
+        let mut rng = StdRng::from_entropy();
+        let url = format!(
+            "postgres://postgres@localhost/zed-test-{}",
+            rng.gen::<u128>()
+        );
+        let runtime = tokio::runtime::Builder::new_current_thread()
+            .enable_io()
+            .enable_time()
+            .build()
+            .unwrap();
+
+        let mut db = runtime.block_on(async {
+            sqlx::Postgres::create_database(&url)
+                .await
+                .expect("failed to create test db");
+            let mut options = ConnectOptions::new(url);
+            options
+                .max_connections(5)
+                .idle_timeout(Duration::from_secs(0));
+            let db = Database::new(options, Executor::Deterministic(background))
+                .await
+                .unwrap();
+            let migrations_path = concat!(env!("CARGO_MANIFEST_DIR"), "/migrations");
+            db.migrate(Path::new(migrations_path), false).await.unwrap();
+            db
+        });
+
+        db.runtime = Some(runtime);
+
+        Self {
+            db: Some(Arc::new(db)),
+            connection: None,
+        }
+    }
+
+    pub fn db(&self) -> &Arc<Database> {
+        self.db.as_ref().unwrap()
+    }
+}
+
+#[macro_export]
+macro_rules! test_both_dbs {
+    ($test_name:ident, $postgres_test_name:ident, $sqlite_test_name:ident) => {
+        #[gpui::test]
+        async fn $postgres_test_name() {
+            let test_db = crate::db::TestDb::postgres(
+                gpui::executor::Deterministic::new(0).build_background(),
+            );
+            $test_name(test_db.db()).await;
+        }
+
+        #[gpui::test]
+        async fn $sqlite_test_name() {
+            let test_db =
+                crate::db::TestDb::sqlite(gpui::executor::Deterministic::new(0).build_background());
+            $test_name(test_db.db()).await;
+        }
+    };
+}
+
+impl Drop for TestDb {
+    fn drop(&mut self) {
+        let db = self.db.take().unwrap();
+        if let sea_orm::DatabaseBackend::Postgres = db.pool.get_database_backend() {
+            db.runtime.as_ref().unwrap().block_on(async {
+                use util::ResultExt;
+                let query = "
+                        SELECT pg_terminate_backend(pg_stat_activity.pid)
+                        FROM pg_stat_activity
+                        WHERE
+                            pg_stat_activity.datname = current_database() AND
+                            pid <> pg_backend_pid();
+                    ";
+                db.pool
+                    .execute(sea_orm::Statement::from_string(
+                        db.pool.get_database_backend(),
+                        query.into(),
+                    ))
+                    .await
+                    .log_err();
+                sqlx::Postgres::drop_database(db.options.get_url())
+                    .await
+                    .log_err();
+            })
+        }
+    }
+}