Auto merge of rust-lang#14342 - davidbarsky:davidbarsky/add-workspace-source-to-status, r=lnicola

Add path of workspace root folders to status output

Hi folks! Just a quick addition to the status output. There are some colleagues of mine who use a mix of Buck and Cargo. A person spent a bit of time this past week trying to figure out there the `rust-project.json` was coming from and pointed out that `rust-analyzer: Status` could be a good place to put this information. rust-analyzer doesn't seem to record the full path of the `Cargo.toml` or the `rust-project.json`, just the root directory. While not perfect, this should be enough for people to unblock themselves on. Here's an example of `rust-analyzer: Status` on the rust-analyzer repo:

```
Workspaces:
Loaded 192 packages across 1 workspace.
Workspace roots: [AbsPath("/Users/dbarsky/Developer/rust-analyzer")]
Analysis:
57mb of files
0b of index symbols (0)
2514 trees, 128 preserved
29535 trees, 128 preserved (Macros)
0b in total

File info:
Crate: rust_analyzer(CrateId(131))
Dependencies: proc_macro=CrateId(5), core=CrateId(2), alloc=CrateId(0), std=CrateId(7), test=CrateId(9), always_assert=CrateId(12), anyhow=CrateId(13), cfg=CrateId(25), crossbeam_channel=CrateId(35), dissimilar=CrateId(41), expect_test=CrateId(46), flycheck=CrateId(50), hir=CrateId(56), hir_def=CrateId(57), hir_ty=CrateId(59), ide=CrateId(63), ide_db=CrateId(66), ide_ssr=CrateId(68), itertools=CrateId(73), jod_thread=CrateId(75), lsp_server=CrateId(83), lsp_types=CrateId(85), mbe=CrateId(87), num_cpus=CrateId(96), oorandom=CrateId(99), parking_lot=CrateId(102), proc_macro_api=CrateId(110), proc_macro_srv=CrateId(111), profile=CrateId(118), project_model=CrateId(119), rayon=CrateId(125), rustc_hash=CrateId(136), scip=CrateId(141), serde=CrateId(145), serde_json=CrateId(147), sourcegen=CrateId(153), stdx=CrateId(155), syntax=CrateId(158), test_utils=CrateId(159), threadpool=CrateId(165), toolchain=CrateId(170), tracing=CrateId(171), tracing_log=CrateId(174), tracing_subscriber=CrateId(175), tracing_tree=CrateId(176), tt=CrateId(177), vfs=CrateId(188), vfs_notify=CrateId(189), xflags=CrateId(192), xshell=CrateId(194)
```

Author: bors

crates/project-model/src/workspace.rs

@@ -450,6 +450,14 @@ impl ProjectWorkspace {
         }
     }
 
+    pub fn workspace_definition_path(&self) -> Option<&AbsPath> {
+        match self {
+            ProjectWorkspace::Cargo { cargo, .. } => Some(cargo.workspace_root()),
+            ProjectWorkspace::Json { project, .. } => Some(project.path()),
+            ProjectWorkspace::DetachedFiles { .. } => None,
+        }
+    }
+
     pub fn find_sysroot_proc_macro_srv(&self) -> Option<AbsPathBuf> {
         match self {
             ProjectWorkspace::Cargo { sysroot: Some(sysroot), .. }

crates/rust-analyzer/src/handlers.rs

@@ -29,7 +29,7 @@ use project_model::{ManifestPath, ProjectWorkspace, TargetKind};
 use serde_json::json;
 use stdx::{format_to, never};
 use syntax::{algo, ast, AstNode, TextRange, TextSize};
-use vfs::AbsPathBuf;
+use vfs::{AbsPath, AbsPathBuf};
 
 use crate::{
     cargo_target_spec::CargoTargetSpec,
@@ -84,6 +84,15 @@ pub(crate) fn handle_analyzer_status(
             snap.workspaces.len(),
             if snap.workspaces.len() == 1 { "" } else { "s" }
         );
+
+        format_to!(
+            buf,
+            "Workspace root folders: {:?}",
+            snap.workspaces
+                .iter()
+                .flat_map(|ws| ws.workspace_definition_path())
+                .collect::<Vec<&AbsPath>>()
+        );
     }
     buf.push_str("\nAnalysis:\n");
     buf.push_str(