Improve filtering of file roots

`ProjectWorkspace::to_roots` now returns a new `ProjectRoot` which contains
information regarding whether or not the given path is part of the current
workspace or an external dependency. This information can then be used in
`ra_batch` and `ra_lsp_server` to implement more advanced filtering. This allows
us to filter some unnecessary folders from external dependencies such as tests,
examples and benches.

3 files changed, 65 insertions, 29 deletions

diff --git a/crates/ra_lsp_server/src/lib.rs b/crates/ra_lsp_server/src/lib.rs
index 59e16a47c..113883bdd 100644
--- a/crates/ra_lsp_server/src/lib.rs
+++ b/crates/ra_lsp_server/src/lib.rs
@@ -4,6 +4,7 @@ mod conv;
 mod main_loop;
 mod markdown;
 mod project_model;
+mod vfs_filter;
 pub mod req;
 pub mod init;
 mod server_world;
diff --git a/crates/ra_lsp_server/src/server_world.rs b/crates/ra_lsp_server/src/server_world.rs
index cf7c17c5c..af4798494 100644
--- a/crates/ra_lsp_server/src/server_world.rs
+++ b/crates/ra_lsp_server/src/server_world.rs
@@ -8,13 +8,14 @@ use ra_ide_api::{
     Analysis, AnalysisChange, AnalysisHost, CrateGraph, FileId, LibraryData,
     SourceRootId
 };
-use ra_vfs::{Vfs, VfsChange, VfsFile, VfsRoot, RootEntry, Filter};
-use relative_path::{RelativePath, RelativePathBuf};
+use ra_vfs::{Vfs, VfsChange, VfsFile, VfsRoot};
+use relative_path::RelativePathBuf;
 use parking_lot::RwLock;
 use failure::format_err;
 
 use crate::{
     project_model::ProjectWorkspace,
+    vfs_filter::IncludeRustFiles,
     Result,
 };
 
@@ -33,40 +34,15 @@ pub struct ServerWorld {
     pub vfs: Arc<RwLock<Vfs>>,
 }
 
-struct IncludeRustFiles;
-
-impl IncludeRustFiles {
-    fn to_entry(path: PathBuf) -> RootEntry {
-        RootEntry::new(path, Box::new(Self {}))
-    }
-}
-
-impl Filter for IncludeRustFiles {
-    fn include_dir(&self, dir_path: &RelativePath) -> bool {
-        const IGNORED_FOLDERS: &[&str] = &["node_modules", "target", ".git"];
-
-        let is_ignored = dir_path.components().any(|c| IGNORED_FOLDERS.contains(&c.as_str()));
-
-        let hidden = dir_path.components().any(|c| c.as_str().starts_with("."));
-
-        !is_ignored && !hidden
-    }
-
-    fn include_file(&self, file_path: &RelativePath) -> bool {
-        file_path.extension() == Some("rs")
-    }
-}
-
 impl ServerWorldState {
     pub fn new(root: PathBuf, workspaces: Vec<ProjectWorkspace>) -> ServerWorldState {
         let mut change = AnalysisChange::new();
 
         let mut roots = Vec::new();
-        roots.push(root.clone());
+        roots.push(IncludeRustFiles::member(root.clone()));
         for ws in workspaces.iter() {
-            roots.extend(ws.to_roots());
+            roots.extend(IncludeRustFiles::from_roots(ws.to_roots()));
         }
-        let roots = roots.into_iter().map(IncludeRustFiles::to_entry).collect::<Vec<_>>();
 
         let (mut vfs, roots) = Vfs::new(roots);
         let roots_to_scan = roots.len();
diff --git a/crates/ra_lsp_server/src/vfs_filter.rs b/crates/ra_lsp_server/src/vfs_filter.rs
new file mode 100644
index 000000000..290aec172
--- /dev/null
+++ b/crates/ra_lsp_server/src/vfs_filter.rs
@@ -0,0 +1,59 @@
+use std::path::PathBuf;

+use ra_project_model::ProjectRoot;

+use ra_vfs::{RootEntry, Filter, RelativePath};

+

+pub struct IncludeRustFiles {

+    /// Is a member of the current workspace

+    is_member: bool,

+}

+

+impl IncludeRustFiles {

+    pub fn from_roots<R>(roots: R) -> impl Iterator<Item = RootEntry>

+    where

+        R: IntoIterator<Item = ProjectRoot>,

+    {

+        roots.into_iter().map(IncludeRustFiles::from_root)

+    }

+

+    pub fn from_root(root: ProjectRoot) -> RootEntry {

+        let is_member = root.is_member();

+        IncludeRustFiles::into_entry(root.into_path(), is_member)

+    }

+

+    #[allow(unused)]

+    pub fn external(path: PathBuf) -> RootEntry {

+        IncludeRustFiles::into_entry(path, false)

+    }

+

+    pub fn member(path: PathBuf) -> RootEntry {

+        IncludeRustFiles::into_entry(path, true)

+    }

+

+    fn into_entry(path: PathBuf, is_member: bool) -> RootEntry {

+        RootEntry::new(path, Box::new(Self { is_member }))

+    }

+}

+

+impl Filter for IncludeRustFiles {

+    fn include_dir(&self, dir_path: &RelativePath) -> bool {

+        const COMMON_IGNORED_DIRS: &[&str] = &["node_modules", "target", ".git"];

+        const EXTERNAL_IGNORED_DIRS: &[&str] = &["examples", "tests", "benches"];

+

+        let is_ignored = if self.is_member {

+            dir_path.components().any(|c| COMMON_IGNORED_DIRS.contains(&c.as_str()))

+        } else {

+            dir_path.components().any(|c| {

+                let path = c.as_str();

+                COMMON_IGNORED_DIRS.contains(&path) || EXTERNAL_IGNORED_DIRS.contains(&path)

+            })

+        };

+

+        let hidden = dir_path.components().any(|c| c.as_str().starts_with("."));

+

+        !is_ignored && !hidden

+    }

+

+    fn include_file(&self, file_path: &RelativePath) -> bool {

+        file_path.extension() == Some("rs")

+    }

+}