Fix: Typo tolerance and clean attach configurations

CHANGELOG.md

@@ -27,6 +27,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **`packageManager` pinned to pnpm@10.33.0** — a different pnpm major regenerated `pnpm-lock.yaml` incompatibly (one contributor diff silently dropped the entire security `overrides` block); the pin plus a CONTRIBUTING note make the wrong-pnpm case fail fast, and the workflows read the pin instead of duplicating a version (#478)
 
 ### Fixed
+- **A typo'd attach `adapterConfig` key now gets a did-you-mean warning instead of silence** — every attach-capable adapter declares the attach keys its debugger actually consumes (`supportedAttachKeys`), and `attach_to_process` warns about keys outside that set with an edit-distance suggestion (`pathMapping (did you mean pathMappings?)`) while still **forwarding** them to the debug adapter untouched, so upstream debugger options the list doesn't model keep working with no mcp-debugger release; keys an adapter's transform genuinely drops keep warning as ignored (#450's contract). The javascript, ruby, java, and dotnet attach transforms also move from closed allowlists to the python/cpp deny-list pattern, so advanced attach options (js-debug's `localRoot`/`remoteRoot`/`sourceMaps`/`skipFiles`/`continueOnAttach`, rdbg's `localfsMap`, netcoredbg's `sourceFileMap`/`symbolOptions`) now genuinely reach the debugger. Thanks @abhijeetnardele24-hash for the `supportedAttachKeys` + did-you-mean design (#466)
 - **Java attach is inspectable on the first try** — the JDI bridge never suspends the VM on attach and java's policy lacked the post-attach pause every other attach adapter has, so the session reported `paused` while the JVM kept running: empty stack, "the debugger may not be paused", and no discoverable recovery. Java now pauses the whole VM after attach (the bridge anchors its stopped event to a thread that can actually report frames), the frameless-thread notes name a real recovery (`threadId` targeting or continue+pause), and `get_local_variables` no longer contradicts the session state (#465)
 - **`get_local_variables` walks down past an empty runtime top frame** — a pause inside a blocking syscall/sleep put a stdlib frame with no locals at `stackFrames[0]` and the tool returned an empty array even though the user frame's locals were one frame down and *already fetched*; extraction now re-anchors to the first frame that yields locals (zero extra DAP round-trips), reports that frame in `frame`, and a `note` discloses the walk-down. Skipped under an explicit `names:` filter (#468)
 - **Statement-anchored breakpoints survive `redefine_classes`** — the hot-swap replant was purely by line, so a line-shifting swap silently rebound a `statement:`-anchored breakpoint to whatever now lives at the old line, reporting `verified: true`; anchors are now re-resolved against the new source (the `restart_debugging` machinery) and re-sent after the redefine so the JDI replant binds the moved lines. The bridge's `replantedBreakpoints` count also no longer drops re-planted function breakpoints (#464)

packages/adapter-cpp/src/cpp-debug-adapter.ts

@@ -103,6 +103,29 @@ export class CppDebugAdapter extends EventEmitter implements IDebugAdapter {
   readonly language = DebugLanguage.CPP;
   readonly name = 'C/C++ Debug Adapter';
 
+  // CodeLLDB attach options (https://github.com/vadimcn/codelldb/blob/master/MANUAL.md)
+  // plus our processId sugar (normalized to pid). Unlisted keys still reach
+  // CodeLLDB (forwarded with a warning) — this list only powers recognition +
+  // typo suggestions (#466).
+  readonly supportedAttachKeys = [
+    'processId',
+    'pid',
+    'program',
+    'stopOnEntry',
+    'waitFor',
+    'initCommands',
+    'preRunCommands',
+    'postRunCommands',
+    'exitCommands',
+    'targetCreateCommands',
+    'processCreateCommands',
+    'expressions',
+    'sourceMap',
+    'sourceLanguages',
+    'relativePathBase',
+    'breakpointMode'
+  ] as const;
+
   private state: AdapterState = AdapterState.UNINITIALIZED;
   private dependencies: AdapterDependencies;
   private lastToolchainValidation: ToolchainValidationResult | undefined;

packages/adapter-dotnet/src/DotnetDebugAdapter.ts

@@ -106,6 +106,19 @@ export class DotnetDebugAdapter extends EventEmitter implements IDebugAdapter {
   readonly language = DebugLanguage.DOTNET;
   readonly name = '.NET Debug Adapter (netcoredbg)';
 
+  // netcoredbg attach options plus the generic keys transformAttachConfig
+  // special-cases (sourcePaths feeds PDB discovery). Unlisted keys still reach
+  // netcoredbg (forwarded with a warning) — this list only powers recognition
+  // + typo suggestions (#466).
+  readonly supportedAttachKeys = [
+    'processId',
+    'justMyCode',
+    'stopOnEntry',
+    'sourcePaths',
+    'sourceFileMap',
+    'symbolOptions'
+  ] as const;
+
   private state: AdapterState = AdapterState.UNINITIALIZED;
   private dependencies: AdapterDependencies;
 
@@ -405,23 +418,42 @@ export class DotnetDebugAdapter extends EventEmitter implements IDebugAdapter {
       }
     }
 
-    const attachConfig = {
+    const {
+      request: _request,
+      __attachMode: _attachMode,
+      host: _host,
+      port: _port,
+      processName: _processName,
+      identifierType: _identifierType,
+      ...rest
+    } = config as Record<string, unknown>;
+    void _request; void _attachMode; void _host; void _port;
+    void _processName; void _identifierType;
+
+    // Advanced passthrough with the normalized netcoredbg attach shape on top
+    // (issues #450/#466). The computed keys stay authoritative — in particular
+    // terminateDebuggee: false (never kill the debuggee on detach) must not be
+    // caller-overridable.
+    const attachConfig: Record<string, unknown> = {
+      ...rest,
       type: 'coreclr',
       request: 'attach',
       name: '.NET: Attach',
       processId: config.processId ? Number(config.processId) : undefined,
       justMyCode: config.justMyCode ?? true,
       // CRITICAL: Never terminate the debuggee on detach
-      terminateDebuggee: false,
-      sourceFileMap: pdbScanDirs ? Object.fromEntries(
-        pdbScanDirs.map(p => [p, p])
-      ) : undefined,
-      symbolOptions: symbolSearchPaths.length > 0
-        ? { searchPaths: symbolSearchPaths, searchMicrosoftSymbolServer: false }
-        : undefined
+      terminateDebuggee: false
     };
+    // Computed values win; a caller-provided sourceFileMap/symbolOptions from
+    // the spread survives when there is nothing computed to replace it.
+    if (pdbScanDirs) {
+      attachConfig.sourceFileMap = Object.fromEntries(pdbScanDirs.map(p => [p, p]));
+    }
+    if (symbolSearchPaths.length > 0) {
+      attachConfig.symbolOptions = { searchPaths: symbolSearchPaths, searchMicrosoftSymbolServer: false };
+    }
 
-    return attachConfig;
+    return attachConfig as LanguageSpecificAttachConfig;
   }
 
   getDefaultAttachConfig(): Partial<GenericAttachConfig> {

packages/adapter-dotnet/tests/unit/dotnet-debug-adapter.test.ts

@@ -465,6 +465,32 @@ describe('DotnetDebugAdapter', () => {
       expect(defaults).toBeDefined();
       expect(defaults!.justMyCode).toBe(true);
     });
+
+    it('forwards unknown attach keys but keeps terminateDebuggee non-overridable (issues #450/#466)', () => {
+      const result = adapter.transformAttachConfig({
+        request: 'attach',
+        __attachMode: true,
+        processId: 1234,
+        terminateDebuggee: true, // must lose to the computed false
+        futureNetcoredbgOption: 'on'
+      } as never) as Record<string, unknown>;
+
+      expect(result.request).toBe('attach');
+      expect(result.__attachMode).toBeUndefined();
+      expect(result.futureNetcoredbgOption).toBe('on');
+      expect(result.terminateDebuggee).toBe(false);
+    });
+
+    it('keeps a caller-provided sourceFileMap when nothing is computed', () => {
+      getProcessExecutableDirMock.mockReturnValue(null);
+      const result = adapter.transformAttachConfig({
+        request: 'attach',
+        processId: 1234,
+        sourceFileMap: { '/remote': '/local' }
+      } as never) as Record<string, unknown>;
+
+      expect(result.sourceFileMap).toEqual({ '/remote': '/local' });
+    });
   });
 
   // ===== Connection Management =====

packages/adapter-java/src/java-debug-adapter.ts

@@ -51,6 +51,21 @@ export class JavaDebugAdapter extends EventEmitter implements IDebugAdapter {
   readonly language = DebugLanguage.JAVA;
   readonly name = 'Java Debug Adapter (JDI)';
 
+  // Keys the JDI bridge's attach handler reads (JdiDapServer.handleAttach)
+  // plus the generic keys transformAttachConfig special-cases. Unlisted keys
+  // still reach the bridge (forwarded with a warning) — this list only powers
+  // recognition + typo suggestions (#466).
+  readonly supportedAttachKeys = [
+    'host',
+    'hostName',
+    'port',
+    'stopOnEntry',
+    'timeout',
+    'sourcePaths',
+    'cwd',
+    'env'
+  ] as const;
+
   private state: AdapterState = AdapterState.UNINITIALIZED;
   private dependencies: AdapterDependencies;
 
@@ -319,30 +334,28 @@ export class JavaDebugAdapter extends EventEmitter implements IDebugAdapter {
   }
 
   transformAttachConfig(config: GenericAttachConfig): LanguageSpecificAttachConfig {
-    const attachConfig: LanguageSpecificAttachConfig = {
+    const {
+      request: _request,
+      __attachMode: _attachMode,
+      processId: _processId,
+      processName: _processName,
+      identifierType: _identifierType,
+      host,
+      port,
+      ...rest
+    } = config as Record<string, unknown>;
+    void _request; void _attachMode; void _processId; void _processName;
+    void _identifierType;
+
+    // Advanced passthrough (the JDI bridge ignores keys it doesn't read) with
+    // the normalized attach shape on top (issues #450/#466).
+    return {
+      ...rest,
       type: 'java',
       request: 'attach',
-      host: config.host || 'localhost',
-      port: config.port,
-    };
-
-    if (config.sourcePaths) {
-      attachConfig.sourcePaths = config.sourcePaths;
-    }
-    if (config.stopOnEntry !== undefined) {
-      attachConfig.stopOnEntry = config.stopOnEntry;
-    }
-    if (config.cwd) {
-      attachConfig.cwd = config.cwd;
-    }
-    if (config.env) {
-      attachConfig.env = config.env;
-    }
-    if (config.timeout !== undefined) {
-      attachConfig.timeout = config.timeout;
-    }
-
-    return attachConfig;
+      host: (host as string | undefined) || 'localhost',
+      port: port as number | undefined,
+    } as LanguageSpecificAttachConfig;
   }
 
   getDefaultAttachConfig(): Partial<GenericAttachConfig> {

packages/adapter-javascript/src/javascript-debug-adapter.ts

@@ -41,6 +41,36 @@ export class JavascriptDebugAdapter extends EventEmitter implements IDebugAdapte
   readonly language = 'javascript' as unknown as DebugLanguage;
   readonly name = 'JavaScript/TypeScript Debug Adapter';
 
+  // js-debug pwa-node attach options https://github.com/microsoft/vscode-js-debug/blob/main/package.json
+  // plus the generic keys transformAttachConfig special-cases. Unlisted keys
+  // still reach js-debug (forwarded with a warning) — this list only powers
+  // recognition + typo suggestions (#466).
+  readonly supportedAttachKeys = [
+    'host',
+    'port',
+    'address',
+    'timeout',
+    'localRoot',
+    'remoteRoot',
+    'smartStep',
+    'skipFiles',
+    'sourceMaps',
+    'sourceMapPathOverrides',
+    'outFiles',
+    'outputCapture',
+    'resolveSourceMapLocations',
+    'pauseForSourceMap',
+    'stopOnEntry',
+    'justMyCode',
+    'cwd',
+    'env',
+    'restart',
+    'continueOnAttach',
+    'trace',
+    'websocketAddress',
+    'attachExistingChildren'
+  ] as const;
+
   private state: AdapterState = AdapterState.UNINITIALIZED;
   private readonly dependencies: AdapterDependencies;
 
@@ -628,25 +658,29 @@ export class JavascriptDebugAdapter extends EventEmitter implements IDebugAdapte
    * mode and JsDebugAdapterPolicy.performHandshake sends a real DAP 'attach'.
    */
   transformAttachConfig(config: GenericAttachConfig): LanguageSpecificAttachConfig {
-    const attachConfig: LanguageSpecificAttachConfig = {
+    const {
+      request: _request,
+      __attachMode: _attachMode,
+      processId: _processId,
+      processName: _processName,
+      identifierType: _identifierType,
+      host,
+      port,
+      ...rest
+    } = config as Record<string, unknown>;
+    void _request; void _attachMode; void _processId; void _processName;
+    void _identifierType;
+
+    // Advanced passthrough (localRoot/remoteRoot, sourceMaps, skipFiles, …)
+    // with the normalized pwa-node attach shape on top (issues #450/#466).
+    return {
+      ...rest,
       type: 'pwa-node',
       request: 'attach',
       name: 'Attach to Node.js process',
-      host: config.host || '127.0.0.1',
-      port: config.port,
-    };
-
-    if (config.stopOnEntry !== undefined) {
-      attachConfig.stopOnEntry = config.stopOnEntry;
-    }
-    if (config.justMyCode !== undefined) {
-      attachConfig.justMyCode = config.justMyCode;
-    }
-    if (config.timeout !== undefined) {
-      attachConfig.timeout = config.timeout;
-    }
-
-    return attachConfig;
+      host: (host as string | undefined) || '127.0.0.1',
+      port: port as number | undefined,
+    } as LanguageSpecificAttachConfig;
   }
 
   getDefaultAttachConfig(): Partial<GenericAttachConfig> {

packages/adapter-javascript/tests/unit/javascript-debug-adapter.transform.test.ts

@@ -330,4 +330,51 @@ describe('JavascriptDebugAdapter.transformLaunchConfig', () => {
       expect(env.NODE_OPTIONS ?? '').not.toContain('exitcode-shim');
     });
   });
+
+  describe('transformAttachConfig passthrough (issues #450/#466)', () => {
+    it('normalizes the pwa-node attach shape and defaults the host', () => {
+      const adapter = new JavascriptDebugAdapter(deps);
+      const cfg = adapter.transformAttachConfig({
+        request: 'attach',
+        port: 9229,
+        stopOnEntry: true,
+        justMyCode: false,
+        timeout: 15000
+      } as any) as Record<string, unknown>;
+
+      expect(cfg.type).toBe('pwa-node');
+      expect(cfg.request).toBe('attach');
+      expect(cfg.host).toBe('127.0.0.1');
+      expect(cfg.port).toBe(9229);
+      expect(cfg.stopOnEntry).toBe(true);
+      expect(cfg.justMyCode).toBe(false);
+      expect(cfg.timeout).toBe(15000);
+    });
+
+    it('forwards advanced js-debug options and strips reserved keys', () => {
+      const adapter = new JavascriptDebugAdapter(deps);
+      const cfg = adapter.transformAttachConfig({
+        request: 'launch', // must not survive: attach transforms pin the request
+        __attachMode: true,
+        processId: 4242,
+        host: '10.0.0.5',
+        port: 9229,
+        localRoot: '/local/src',
+        remoteRoot: '/app',
+        sourceMaps: false,
+        skipFiles: ['<node_internals>/**'],
+        continueOnAttach: true
+      } as any) as Record<string, unknown>;
+
+      expect(cfg.request).toBe('attach');
+      expect(cfg.__attachMode).toBeUndefined();
+      expect(cfg.processId).toBeUndefined();
+      expect(cfg.host).toBe('10.0.0.5');
+      expect(cfg.localRoot).toBe('/local/src');
+      expect(cfg.remoteRoot).toBe('/app');
+      expect(cfg.sourceMaps).toBe(false);
+      expect(cfg.skipFiles).toEqual(['<node_internals>/**']);
+      expect(cfg.continueOnAttach).toBe(true);
+    });
+  });
 });

packages/adapter-python/src/python-debug-adapter.ts

@@ -84,6 +84,29 @@ export class PythonDebugAdapter extends EventEmitter implements IDebugAdapter {
   readonly language = DebugLanguage.PYTHON;
   readonly name = 'Python Debug Adapter';
 
+  // debugpy attach schema https://github.com/microsoft/debugpy/wiki/Debug-configuration-settings
+  // plus the generic keys transformAttachConfig special-cases. Unlisted keys
+  // still reach debugpy (forwarded with a warning) — this list only powers
+  // recognition + typo suggestions (#466).
+  readonly supportedAttachKeys = [
+    'host',
+    'port',
+    'justMyCode',
+    'pathMappings',
+    'redirectOutput',
+    'showReturnValue',
+    'subProcess',
+    'clientOS',
+    'django',
+    'jinja',
+    'stopOnEntry',
+    'cwd',
+    'env',
+    'logToFile',
+    'steppingResumesAllThreads',
+    'rules'
+  ] as const;
+
   private state: AdapterState = AdapterState.UNINITIALIZED;
   private dependencies: AdapterDependencies;