[Lldb-commits] [lldb] [lldb-dap] Add process picker command to VS Code extension (PR #197513)

[Sergei Druzhkov via lldb-commits]

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@@ -0,0 +1,132 @@
+import { execFile } from "node:child_process";
+import * as path from "node:path";
+import { promisify } from "node:util";
+import * as vscode from "vscode";
+
+import { createDebugAdapterExecutable } from "../debug-adapter-factory";
+import { LogFilePathProvider } from "../logging";
+import { LldbDapProcessTree, Process } from "../process-tree";
+
+const exec = promisify(execFile);
+
+/**
+ * Cache of which lldb-dap binaries have been observed to support the
+ * `--list-processes` flag, keyed by executable path. We probe once per path,
+ * but only remember successful probes — a transient failure (binary still
+ * building, EBUSY, etc.) should not poison the cache for the rest of the
+ * session.
+ */
+const listProcessesSupportCache = new Map<string, Promise<boolean>>();
+
+/** Probes `<exe> --help` to see whether `--list-processes` is advertised. */
+function isListProcessesSupported(exe: string): Promise<boolean> {
+  const cached = listProcessesSupportCache.get(exe);
+  if (cached) {
+    return cached;
+  }
+  const probe = exec(exe, ["--help"]).then(({ stdout }) =>
+    /--list-processes/.test(stdout),
+  );
+  listProcessesSupportCache.set(exe, probe);
+  // Drop failed probes so the next attempt can retry.
+  probe.catch(() => {
+    if (listProcessesSupportCache.get(exe) === probe) {
+      listProcessesSupportCache.delete(exe);
+    }
+  });
+  return probe.catch(() => false);
+}
+
+interface ProcessQuickPick extends vscode.QuickPickItem {
+  processId: number;
+}
+
+/**
+ * Prompts the user to select a running process, enumerated by `lldb-dap
+ * --list-processes`. When invoked from `resolveDebugConfiguration` the caller
+ * forwards the in-flight configuration so we can target the right lldb-dap
+ * binary and platform (for remote attach).
+ *
+ * @returns the pid of the selected process, or `undefined` if the user
+ *   cancelled or the picker failed (in which case an error has already been
+ *   shown).
+ */
+export async function pickProcess(
+  logger: vscode.LogOutputChannel,
+  logFilePath: LogFilePathProvider,
+  folder?: vscode.WorkspaceFolder,
+  debugConfiguration?: vscode.DebugConfiguration,
+): Promise<number | undefined> {
+  const executable = await createDebugAdapterExecutable(
+    logger,
+    logFilePath,
+    folder,
+    debugConfiguration ?? {
+      type: "lldb-dap",
+      request: "attach",
+      name: "Attach",
+    },
+  );
+
+  if (!(await isListProcessesSupported(executable.command))) {
+    await vscode.window.showErrorMessage(
+      "The lldb-dap binary does not support the --list-processes flag " +
+        "required by the process picker. Please update to a newer version.",
+      { modal: true, detail: executable.command },
+    );
+    return undefined;
+  }
+
+  const tree = new LldbDapProcessTree(executable.command, {
+    platformName: debugConfiguration?.platformName,
+    platformUrl: debugConfiguration?.platformUrl,
----------------
DrSergei wrote:

I think we should add mention of `platformUrl` into package.json

https://github.com/llvm/llvm-project/pull/197513