[vscode-lldb] Add VS Code commands for high level debug workflow (#151827)

This allows other debugger extensions to leverage the `lldb-dap`
extension's settings and logic (e.g. "Server Mode").

Other debugger extensions can invoke these commands to resolve
configuration, create adapter descriptor, and get the `lldb-dap` process
for state tracking, additional interaction, and telemetry.

VS Code commands added:
* `lldb-dap.resolveDebugConfiguration`
* `lldb-dap.resolveDebugConfigurationWithSubstitutedVariables`
* `lldb-dap.createDebugAdapterDescriptor`
* `lldb-dap.getServerProcess`

lldb/docs/resources/lldbdap.md

@@ -170,3 +170,26 @@ This is also very simple, just run:
 ```bash
 npm run format
 ```
+
+## Working with the VS Code extension from another extension
+
+The VS Code extension exposes the following [VS Code
+commands](https://code.visualstudio.com/api/extension-guides/command),
+which can be invoked by other debugger extensions to leverage this extension's
+settings and logic. The commands help resolve configuration, create adapter
+descriptor, and get the lldb-dap process for state tracking, additional
+interaction, and telemetry.
+
+```
+// Resolve debug configuration
+const resolvedConfiguration = await vscode.commands.executeCommand("lldb-dap.resolveDebugConfiguration", folder, configuration, token);
+
+// Resolve debug configuration with substituted variables
+const resolvedConfigurationWithSubstitutedVariables = await vscode.commands.executeCommand("lldb-dap.resolveDebugConfigurationWithSubstitutedVariables", folder, configuration, token);
+
+// Create debug adapter descriptor
+const adapterDescriptor = await vscode.commands.executeCommand("lldb-dap.createDebugAdapterDescriptor", session, executable);
+
+// Get DAP server process
+const process = await vscode.commands.executeCommand("lldb-dap.getServerProcess");
+```

lldb/tools/lldb-dap/src-ts/debug-adapter-factory.ts

@@ -217,7 +217,15 @@ export class LLDBDapDescriptorFactory
   constructor(
     private readonly logger: vscode.LogOutputChannel,
     private logFilePath: LogFilePathProvider,
-  ) {}
+  ) {
+    vscode.commands.registerCommand(
+      "lldb-dap.createDebugAdapterDescriptor",
+      (
+        session: vscode.DebugSession,
+        executable: vscode.DebugAdapterExecutable | undefined,
+      ) => this.createDebugAdapterDescriptor(session, executable),
+    );
+  }
 
   async createDebugAdapterDescriptor(
     session: vscode.DebugSession,

lldb/tools/lldb-dap/src-ts/debug-configuration-provider.ts

@@ -76,7 +76,29 @@ export class LLDBDapConfigurationProvider
     private readonly server: LLDBDapServer,
     private readonly logger: vscode.LogOutputChannel,
     private readonly logFilePath: LogFilePathProvider,
-  ) {}
+  ) {
+    vscode.commands.registerCommand(
+      "lldb-dap.resolveDebugConfiguration",
+      (
+        folder: vscode.WorkspaceFolder | undefined,
+        debugConfiguration: vscode.DebugConfiguration,
+        token?: vscode.CancellationToken,
+      ) => this.resolveDebugConfiguration(folder, debugConfiguration, token),
+    );
+    vscode.commands.registerCommand(
+      "lldb-dap.resolveDebugConfigurationWithSubstitutedVariables",
+      (
+        folder: vscode.WorkspaceFolder | undefined,
+        debugConfiguration: vscode.DebugConfiguration,
+        token?: vscode.CancellationToken,
+      ) =>
+        this.resolveDebugConfigurationWithSubstitutedVariables(
+          folder,
+          debugConfiguration,
+          token,
+        ),
+    );
+  }
 
   async resolveDebugConfiguration(
     folder: vscode.WorkspaceFolder | undefined,

lldb/tools/lldb-dap/src-ts/lldb-dap-server.ts

@@ -12,6 +12,13 @@ export class LLDBDapServer implements vscode.Disposable {
   private serverProcess?: child_process.ChildProcessWithoutNullStreams;
   private serverInfo?: Promise<{ host: string; port: number }>;
 
+  constructor() {
+    vscode.commands.registerCommand(
+      "lldb-dap.getServerProcess",
+      () => this.serverProcess,
+    );
+  }
+
   /**
    * Starts the server with the provided options. The server will be restarted or reused as
    * necessary.