diff --git a/crates/rust-analyzer/src/handlers/request.rs b/crates/rust-analyzer/src/handlers/request.rs
index 2ee563eefc7b..4a6a546848bd 100644
--- a/crates/rust-analyzer/src/handlers/request.rs
+++ b/crates/rust-analyzer/src/handlers/request.rs
@@ -826,8 +826,11 @@ pub(crate) fn handle_runnables(
         }
         let mut runnable = to_proto::runnable(&snap, runnable)?;
         if expect_test {
-            runnable.label = format!("{} + expect", runnable.label);
-            runnable.args.expect_test = Some(true);
+            #[allow(irrefutable_let_patterns)]
+            if let lsp_ext::RunnableArgs::Cargo(r) = &mut runnable.args {
+                runnable.label = format!("{} + expect", runnable.label);
+                r.expect_test = Some(true);
+            }
         }
         res.push(runnable);
     }
@@ -851,14 +854,14 @@ pub(crate) fn handle_runnables(
                     ),
                     location: None,
                     kind: lsp_ext::RunnableKind::Cargo,
-                    args: lsp_ext::CargoRunnableArgs {
+                    args: lsp_ext::RunnableArgs::Cargo(lsp_ext::CargoRunnableArgs {
                         workspace_root: Some(spec.workspace_root.clone().into()),
                         override_cargo: config.override_cargo.clone(),
                         cargo_args,
                         cargo_extra_args: config.cargo_extra_args.clone(),
                         executable_args: Vec::new(),
                         expect_test: None,
-                    },
+                    }),
                 })
             }
         }
@@ -868,14 +871,14 @@ pub(crate) fn handle_runnables(
                     label: "cargo check --workspace".to_owned(),
                     location: None,
                     kind: lsp_ext::RunnableKind::Cargo,
-                    args: lsp_ext::CargoRunnableArgs {
+                    args: lsp_ext::RunnableArgs::Cargo(lsp_ext::CargoRunnableArgs {
                         workspace_root: None,
                         override_cargo: config.override_cargo,
                         cargo_args: vec!["check".to_owned(), "--workspace".to_owned()],
                         cargo_extra_args: config.cargo_extra_args,
                         executable_args: Vec::new(),
                         expect_test: None,
-                    },
+                    }),
                 });
             }
         }
diff --git a/crates/rust-analyzer/src/lsp/ext.rs b/crates/rust-analyzer/src/lsp/ext.rs
index c7bb6fbb7e12..41814190ba29 100644
--- a/crates/rust-analyzer/src/lsp/ext.rs
+++ b/crates/rust-analyzer/src/lsp/ext.rs
@@ -423,7 +423,14 @@ pub struct Runnable {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub location: Option<lsp_types::LocationLink>,
     pub kind: RunnableKind,
-    pub args: CargoRunnableArgs,
+    pub args: RunnableArgs,
+}
+
+#[derive(Deserialize, Serialize, Debug)]
+#[serde(rename_all = "camelCase")]
+#[serde(untagged)]
+pub enum RunnableArgs {
+    Cargo(CargoRunnableArgs),
 }
 
 #[derive(Serialize, Deserialize, Debug)]
diff --git a/crates/rust-analyzer/src/lsp/to_proto.rs b/crates/rust-analyzer/src/lsp/to_proto.rs
index 9c5c716bcf5e..8dc2744a6327 100644
--- a/crates/rust-analyzer/src/lsp/to_proto.rs
+++ b/crates/rust-analyzer/src/lsp/to_proto.rs
@@ -1364,14 +1364,14 @@ pub(crate) fn runnable(
                 label,
                 location: Some(location),
                 kind: lsp_ext::RunnableKind::Cargo,
-                args: lsp_ext::CargoRunnableArgs {
+                args: lsp_ext::RunnableArgs::Cargo(lsp_ext::CargoRunnableArgs {
                     workspace_root: Some(workspace_root.into()),
                     override_cargo: config.override_cargo,
                     cargo_args,
                     cargo_extra_args: config.cargo_extra_args,
                     executable_args,
                     expect_test: None,
-                },
+                }),
             })
         }
         None => {
@@ -1384,14 +1384,14 @@ pub(crate) fn runnable(
                 label,
                 location: Some(location),
                 kind: lsp_ext::RunnableKind::Cargo,
-                args: lsp_ext::CargoRunnableArgs {
+                args: lsp_ext::RunnableArgs::Cargo(lsp_ext::CargoRunnableArgs {
                     workspace_root: None,
                     override_cargo: config.override_cargo,
                     cargo_args,
                     cargo_extra_args: config.cargo_extra_args,
                     executable_args,
                     expect_test: None,
-                },
+                }),
             })
         }
     }
@@ -1418,11 +1418,12 @@ pub(crate) fn code_lens(
             };
             let r = runnable(snap, run)?;
 
+            let has_root = match &r.args {
+                lsp_ext::RunnableArgs::Cargo(c) => c.workspace_root.is_some(),
+            };
+
             let lens_config = snap.config.lens();
-            if lens_config.run
-                && client_commands_config.run_single
-                && r.args.workspace_root.is_some()
-            {
+            if lens_config.run && client_commands_config.run_single && has_root {
                 let command = command::run_single(&r, &title);
                 acc.push(lsp_types::CodeLens {
                     range: annotation_range,