fix(debugger): debug uv / poetry run configurations in the project's environment

A Python run configuration such as `uv run python main.py` or `poetry run pytest` was debugged as `python3 -m uv run python main.py`: debugpy treated the manager as a console script and ran it as a module, so the session failed or ran outside the project's environment.

Configurations that run through uv, poetry, pdm, pipenv, hatch or rye now pass the manager to debugpy as the debuggee's interpreter (`["uv", "run", "python"]`) and keep the script, `-m` module or tool (`uv run pytest` → module `pytest`) as the target. The adapter and its launcher run on a plain interpreter (`debugLauncherPython`), which the backend now prefers when choosing the adapter's command.

crates/ide-dap/src/lib.rs

@@ -589,11 +589,12 @@ impl DebugManager {
         if let Some(command) = custom_command(&spec.command) {
             spec.command = command;
         }
-        // debugpy: run the adapter with the debuggee's interpreter (venvs carry their own debugpy).
+        // debugpy: run the adapter with the debuggee's interpreter (venvs carry their own debugpy),
+        // or with the launcher's when the debuggee runs through a manager (`uv run python`).
         if config.adapter == "debugpy" {
-            let python = match arguments.get("python") {
-                Some(Value::String(p)) => Some(p.clone()),
-                Some(Value::Array(a)) => a.first().and_then(Value::as_str).map(str::to_owned),
+            let python = match (arguments.get("debugLauncherPython"), arguments.get("python")) {
+                (Some(Value::String(p)), _) | (_, Some(Value::String(p))) => Some(p.clone()),
+                (_, Some(Value::Array(a))) => a.first().and_then(Value::as_str).map(str::to_owned),
                 _ => None,
             };
             if let Some(python) = python {

src/features/debugger/__tests__/launch.test.ts

@@ -79,6 +79,27 @@ describe("run config → launch config", () => {
     expect(extra(globalPytest).python).toBe("python3");
   });
 
+  it("debugpy: uv / poetry run the debuggee in the project's environment", () => {
+    const debug = (command: string, args: string[]) =>
+      launchConfigFor(rc({ kind: "python", command, args, debugAdapter: "debugpy" }), "/p")!;
+
+    const script = debug("uv", ["run", "python", "main.py", "-v"]);
+    expect(script.program).toBe("/p/main.py");
+    expect(script.args).toEqual(["-v"]);
+    expect(extra(script)).toMatchObject({ python: ["uv", "run", "python"], debugLauncherPython: "python3" });
+    expect(extra(script).module).toBeUndefined();
+
+    const mod = debug("poetry", ["run", "python3", "-m", "app"]);
+    expect(extra(mod)).toMatchObject({ module: "app", python: ["poetry", "run", "python3"] });
+
+    const tool = debug("uv", ["run", "pytest", "-x"]);
+    expect(extra(tool)).toMatchObject({ module: "pytest", python: ["uv", "run", "python"] });
+    expect(tool.args).toEqual(["-x"]);
+
+    const django = debug("pdm", ["run", "python", "manage.py", "runserver"]);
+    expect(extra(django)).toMatchObject({ django: true, python: ["pdm", "run", "python"] });
+  });
+
   it("js-debug: npm scripts run through the package manager, node scripts directly", () => {
     const npm = launchConfigFor(
       rc({ kind: "npm", command: "pnpm", args: ["run", "dev"], cwd: "web", debugAdapter: "js-debug" }),

src/features/debugger/launch.ts

@@ -58,15 +58,20 @@ function cargoLaunch(rc: RunConfig, cwd: string, adapter: string): LaunchConfig
   };
 }
 
+const PYTHON_NAME = /^python[\d.]*(\.exe)?$/;
+
 function pythonFor(rc: RunConfig, cwd: string): string {
   const cmd = rc.command;
   const name = cmd.split("/").pop() ?? cmd;
-  if (/^python[\d.]*(\.exe)?$/.test(name)) return resolveCommand(cmd, cwd);
+  if (PYTHON_NAME.test(name)) return resolveCommand(cmd, cwd);
   // A venv tool such as `.venv/bin/pytest`: use the interpreter next to it.
   if (cmd.includes("/")) return resolveCommand(cmd.slice(0, cmd.lastIndexOf("/") + 1) + "python", cwd);
   return "python3";
 }
 
+/** Project managers whose `run` executes in the project's environment (`uv run python …`). */
+const PYTHON_RUNNERS = new Set(["uv", "poetry", "pdm", "pipenv", "hatch", "rye"]);
+
 function debugpyLaunch(rc: RunConfig, cwd: string): LaunchConfig {
   const out = base(rc, "debugpy", cwd);
   const dbg = workflowSettings().debugger;
@@ -78,19 +83,29 @@ function debugpyLaunch(rc: RunConfig, cwd: string): LaunchConfig {
     redirectOutput: true,
   };
   if (dbg.python.gevent) extra.gevent = true;
-  const name = rc.command.split("/").pop() ?? rc.command;
-  const isPython = /^python[\d.]*(\.exe)?$/.test(name);
-  if (!isPython) {
+  const name = (rc.command.split("/").pop() ?? rc.command).replace(/\.exe$/, "");
+  let args = rc.args;
+  let tool: string | null = PYTHON_NAME.test(name) ? null : name;
+  if (PYTHON_RUNNERS.has(name) && args[0] === "run" && args[1]) {
+    // The debuggee runs through the manager (`uv run python <debugpy> …`) to get the project's
+    // environment; the adapter and its launcher need a plain interpreter.
+    const python = PYTHON_NAME.test(args[1]) ? args[1] : "python";
+    extra.python = [resolveCommand(rc.command, cwd), "run", python];
+    extra.debugLauncherPython = "python3";
+    tool = PYTHON_NAME.test(args[1]) ? null : args[1];
+    args = args.slice(2);
+  }
+  if (tool) {
     // A console script (`pytest`, `uvicorn`, …): run it as a module.
-    extra.module = name.replace(/\.exe$/, "");
-    out.args = [...rc.args];
-  } else if (rc.args[0] === "-m" && rc.args[1]) {
-    extra.module = rc.args[1];
-    out.args = rc.args.slice(2);
-  } else if (rc.args[0]) {
-    out.program = join(cwd, rc.args[0]);
-    out.args = rc.args.slice(1);
-    if (rc.args[0].endsWith("manage.py")) extra.django = true;
+    extra.module = tool;
+    out.args = [...args];
+  } else if (args[0] === "-m" && args[1]) {
+    extra.module = args[1];
+    out.args = args.slice(2);
+  } else if (args[0]) {
+    out.program = join(cwd, args[0]);
+    out.args = args.slice(1);
+    if (args[0].endsWith("manage.py")) extra.django = true;
   }
   out.extraJson = JSON.stringify(extra);
   return out;