Fix tests on windows

Author: MichaReiser

Cargo.lock

@@ -69,7 +69,6 @@ impl TestCase {
         Some(all_events)
     }
 
-    #[cfg(unix)]
     fn take_watch_changes(&self) -> Vec<watch::ChangeEvent> {
         self.try_take_watch_changes(Duration::from_secs(10))
             .expect("Expected watch changes but observed none")
@@ -1349,3 +1348,98 @@ fn nested_packages_delete_root() -> anyhow::Result<()> {
 
     Ok(())
 }
+
+#[test]
+fn added_package() -> anyhow::Result<()> {
+    let mut case = setup([
+        (
+            "pyproject.toml",
+            r#"
+            [project]
+            name = "inner"
+
+            [tool.knot.workspace]
+            members = ["packages/*"]
+            "#,
+        ),
+        (
+            "packages/a/pyproject.toml",
+            r#"
+            [project]
+            name = "a"
+            "#,
+        ),
+    ])?;
+
+    assert_eq!(case.db().workspace().packages(case.db()).len(), 2);
+
+    std::fs::create_dir(case.workspace_path("packages/b").as_std_path())
+        .context("failed to create folder for package 'b'")?;
+
+    // It seems that the file watcher won't pick up on file changes shortly after the folder
+    // was created... I suspect this is because most file watchers don't support recursive
+    // file watching. Instead, file-watching libraries manually implement recursive file watching
+    // by setting a watcher for each directory. But doing this obviously "lags" behind.
+    case.take_watch_changes();
+
+    std::fs::write(
+        case.workspace_path("packages/b/pyproject.toml")
+            .as_std_path(),
+        r#"
+            [project]
+            name = "b"
+            "#,
+    )
+    .context("failed to write pyproject.toml for package b")?;
+
+    let changes = case.stop_watch();
+
+    case.apply_changes(changes);
+
+    assert_eq!(case.db().workspace().packages(case.db()).len(), 3);
+
+    Ok(())
+}
+
+#[test]
+fn removed_package() -> anyhow::Result<()> {
+    let mut case = setup([
+        (
+            "pyproject.toml",
+            r#"
+            [project]
+            name = "inner"
+
+            [tool.knot.workspace]
+            members = ["packages/*"]
+            "#,
+        ),
+        (
+            "packages/a/pyproject.toml",
+            r#"
+            [project]
+            name = "a"
+            "#,
+        ),
+        (
+            "packages/b/pyproject.toml",
+            r#"
+            [project]
+            name = "b"
+            "#,
+        ),
+    ])?;
+
+    assert_eq!(case.db().workspace().packages(case.db()).len(), 3);
+
+    std::fs::remove_dir_all(case.workspace_path("packages/b").as_std_path())
+        .context("failed to remove package 'b'")?;
+
+    let changes = case.stop_watch();
+
+    case.apply_changes(changes);
+
+    assert_eq!(case.db().workspace().packages(case.db()).len(), 2);
+
+    Ok(())
+}

crates/red_knot/tests/file_watching.rs

@@ -35,7 +35,8 @@ tracing = { workspace = true }
 
 [dev-dependencies]
 ruff_db = { workspace = true, features = ["testing"] }
-insta = { workspace = true }
+insta = { workspace = true, features = ["filters"] }
+regex = { workspace = true }
 tempfile = { workspace = true }
 
 [features]

crates/red_knot_workspace/Cargo.toml

@@ -1,6 +1,6 @@
 use crate::db::{Db, RootDatabase};
 use crate::watch;
-use crate::watch::{CreatedKind, DeletedKind};
+use crate::watch::{ChangeEvent, CreatedKind, DeletedKind};
 use crate::workspace::settings::Configuration;
 use crate::workspace::{Workspace, WorkspaceMetadata};
 use red_knot_python_semantic::Program;
@@ -57,7 +57,9 @@ impl RootDatabase {
                     // Changes to ignore files or settings can change the workspace structure or add/remove files
                     // from packages.
                     if let Some(package) = workspace.package(self, path) {
-                        if package.root(self) == workspace.root(self) {
+                        if package.root(self) == workspace.root(self)
+                            || matches!(change, ChangeEvent::Deleted { .. })
+                        {
                             workspace_change = true;
                         }
 

crates/red_knot_workspace/src/db/changes.rs

@@ -566,6 +566,12 @@ impl PackageTree {
         }
     }
 
+    // The package table should never be empty, that's why `is_empty` makes little sense
+    #[allow(clippy::len_without_is_empty)]
+    pub fn len(&self) -> usize {
+        self.0.len()
+    }
+
     pub fn iter(&self) -> PackageTreeIter {
         PackageTreeIter(self.0.values())
     }