Merge #774

774: Batch crate & command r=matklad a=flodiebold

This adds a new crate, `ra_batch`, which is intended for scenarios where you're loading a workspace once and then running some analyses using the HIR API. Also, it adds a command to `ra_cli` which uses that to type-check all crates in a workspace and print some statistics:

E.g. in rust-analyzer:
```
> $ time target/release/ra_cli analysis-stats
Database loaded, 21 roots
Crates in this dir: 28
Total modules found: 231
Total declarations: 3694
Total functions: 2408
Total expressions: 47017
Expressions of unknown type: 19826 (42%)
Expressions of partially unknown type: 4482 (9%)
target/release/ra_cli analysis-stats  3,23s user 0,60s system 100% cpu 3,821 total
```

Or in rust-lang/rust:
```
> $ time ../opensource/rust-analyzer/target/release/ra_cli analysis-stats
Database loaded, 77 roots
Crates in this dir: 130
Total modules found: 1820
Total declarations: 35038
Total functions: 25914
Total expressions: 753678
Expressions of unknown type: 337975 (44%)
Expressions of partially unknown type: 92314 (12%)
../opensource/rust-analyzer/target/release/ra_cli analysis-stats  13,45s user 2,08s system 100% cpu 15,477 total
```

~This still needs a test. Type-checking all of rust-analyzer sadly takes almost a minute when compiled in debug mode :sweat_smile: So I'll need to add something simpler (maybe just looking at a few modules).~

Co-authored-by: Florian Diebold <[email protected]>

1 files changed, 1 insertions, 3 deletions

diff --git a/crates/ra_lsp_server/src/server_world.rs b/crates/ra_lsp_server/src/server_world.rs
index f97d240fa..4a68c019f 100644
--- a/crates/ra_lsp_server/src/server_world.rs
+++ b/crates/ra_lsp_server/src/server_world.rs
@@ -47,10 +47,8 @@ impl ServerWorldState {
                 roots.push(krate.root_dir(&ws.sysroot).to_path_buf())
             }
         }
-        roots.sort();
-        roots.dedup();
-        let roots_to_scan = roots.len();
         let (mut vfs, roots) = Vfs::new(roots);
+        let roots_to_scan = roots.len();
         for r in roots {
             let is_local = vfs.root2path(r).starts_with(&root);
             change.add_root(SourceRootId(r.0.into()), is_local);