1 files changed, 75 insertions, 0 deletions

diff --git a/crates/ra_hir_def/src/test_db.rs b/crates/ra_hir_def/src/test_db.rs
new file mode 100644
index 000000000..8ee8e40d0
--- /dev/null
+++ b/crates/ra_hir_def/src/test_db.rs
@@ -0,0 +1,75 @@
+//! Database used for testing `hir_def`.
+
+use std::{
+    panic,
+    sync::{Arc, Mutex},
+};
+
+use ra_db::{salsa, CrateId, FileId, FileLoader, FileLoaderDelegate, RelativePath};
+
+#[salsa::database(
+    ra_db::SourceDatabaseExtStorage,
+    ra_db::SourceDatabaseStorage,
+    hir_expand::db::AstDatabaseStorage,
+    crate::db::InternDatabaseStorage,
+    crate::db::DefDatabase2Storage
+)]
+#[derive(Debug, Default)]
+pub struct TestDB {
+    runtime: salsa::Runtime<TestDB>,
+    events: Mutex<Option<Vec<salsa::Event<TestDB>>>>,
+}
+
+impl salsa::Database for TestDB {
+    fn salsa_runtime(&self) -> &salsa::Runtime<Self> {
+        &self.runtime
+    }
+
+    fn salsa_event(&self, event: impl Fn() -> salsa::Event<TestDB>) {
+        let mut events = self.events.lock().unwrap();
+        if let Some(events) = &mut *events {
+            events.push(event());
+        }
+    }
+}
+
+impl panic::RefUnwindSafe for TestDB {}
+
+impl FileLoader for TestDB {
+    fn file_text(&self, file_id: FileId) -> Arc<String> {
+        FileLoaderDelegate(self).file_text(file_id)
+    }
+    fn resolve_relative_path(
+        &self,
+        anchor: FileId,
+        relative_path: &RelativePath,
+    ) -> Option<FileId> {
+        FileLoaderDelegate(self).resolve_relative_path(anchor, relative_path)
+    }
+    fn relevant_crates(&self, file_id: FileId) -> Arc<Vec<CrateId>> {
+        FileLoaderDelegate(self).relevant_crates(file_id)
+    }
+}
+
+impl TestDB {
+    pub fn log(&self, f: impl FnOnce()) -> Vec<salsa::Event<TestDB>> {
+        *self.events.lock().unwrap() = Some(Vec::new());
+        f();
+        self.events.lock().unwrap().take().unwrap()
+    }
+
+    pub fn log_executed(&self, f: impl FnOnce()) -> Vec<String> {
+        let events = self.log(f);
+        events
+            .into_iter()
+            .filter_map(|e| match e.kind {
+                // This pretty horrible, but `Debug` is the only way to inspect
+                // QueryDescriptor at the moment.
+                salsa::EventKind::WillExecute { database_key } => {
+                    Some(format!("{:?}", database_key))
+                }
+                _ => None,
+            })
+            .collect()
+    }
+}