Pass --all-targets to cargo invocation
```

Which would mean that every time Zed saves, a `cargo check --workspace --all-targets` command is run, checking the entire project (workspace), lib, doc, test, bin, bench and [other targets](https://doc.rust-lang.org/cargo/reference/cargo-targets.html).

While that works fine on small projects, it does not scale well.

The alternatives would be to use [tasks](../tasks.md), as Zed already provides a `cargo check --workspace --all-targets` task and the ability to cmd/ctrl-click on the terminal output to navigate to the error, and limit or turn off the check on save feature entirely.

Check on save feature is responsible for returning part of the diagnostics based on cargo check output, so turning it off will limit rust-analyzer with its own [diagnostics](https://rust-analyzer.github.io/book/diagnostics.html).

Consider more `rust-analyzer.cargo.` and `rust-analyzer.check.` and `rust-analyzer.diagnostics.` settings from the manual for more fine-grained configuration.
Here's a snippet for Zed settings.json (the language server will restart automatically after the `lsp.rust-analyzer` section is edited and saved):

```json
{
  "lsp": {
    "rust-analyzer": {
      "initialization_options": {
        // get more cargo-less diagnostics from rust-analyzer,
        // which might include false-positives (those can be turned off by their names)
        "diagnostics": {
          "experimental": {
            "enable": true
          }
        },
        // To disable the checking entirely
        // (ignores all cargo and check settings below)
        "checkOnSave": false,
        // To check the `lib` target only.
        "cargo": {
          "allTargets": false
        },
        // Use `-p` instead of `--workspace` for cargo check
        "check": {
          "workspace": false
        }
      }
    }
  }
}
```

### Multi-project workspaces

If you want rust-analyzer to analyze multiple Rust projects in the same folder that are not listed in `[members]` in the Cargo workspace,
you can list them in `linkedProjects` in the local project settings:

```json
{
  "lsp": {
    "rust-analyzer": {
      "initialization_options": {
        "linkedProjects": ["./path/to/a/Cargo.toml", "./path/to/b/Cargo.toml"]
      }
    }
  }
}
```

### Snippets

There's a way get custom completion items from rust-analyzer, that will transform the code according to the snippet body:

```json
{
  "lsp": {
    "rust-analyzer": {
      "initialization_options": {
        "completion": {
          "snippets": {
            "custom": {
              "Arc::new": {
                "postfix": "arc",
                "body": ["Arc::new(${receiver})"],
                "requires": "std::sync::Arc",
                "scope": "expr"
              },
              "Some": {
                "postfix": "some",
                "body": ["Some(${receiver})"],
                "scope": "expr"
              },
              "Ok": {
                "postfix": "ok",
                "body": ["Ok(${receiver})"],
                "scope": "expr"
              },
              "Rc::new": {
                "postfix": "rc",
                "body": ["Rc::new(${receiver})"],
                "requires": "std::rc::Rc",
                "scope": "expr"
              },
              "Box::pin": {
                "postfix": "boxpin",
                "body": ["Box::pin(${receiver})"],
                "requires": "std::boxed::Box",
                "scope": "expr"
              },
              "vec!": {
                "postfix": "vec",
                "body": ["vec![${receiver}]"],
                "description": "vec![]",
                "scope": "expr"
              }
            }
          }
        }
      }
    }
  }
}
```