Fix unsafe assertions in code_assist folder. (#19706)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

packages/core/src/code_assist/converter.ts

@@ -181,6 +181,16 @@ function maybeToContent(content?: ContentUnion): Content | undefined {
   return toContent(content);
 }
 
+function isPart(c: ContentUnion): c is PartUnion {
+  return (
+    typeof c === 'object' &&
+    c !== null &&
+    !Array.isArray(c) &&
+    !('parts' in c) &&
+    !('role' in c)
+  );
+}
+
 function toContent(content: ContentUnion): Content {
   if (Array.isArray(content)) {
     // it's a PartsUnion[]
@@ -196,7 +206,7 @@ function toContent(content: ContentUnion): Content {
       parts: [{ text: content }],
     };
   }
-  if ('parts' in content) {
+  if (!isPart(content)) {
     // it's a Content - process parts to handle thought filtering
     return {
       ...content,
@@ -208,8 +218,7 @@ function toContent(content: ContentUnion): Content {
   // it's a Part
   return {
     role: 'user',
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-    parts: [toPart(content as Part)],
+    parts: [toPart(content)],
   };
 }
 

packages/core/src/code_assist/experiments/experiments.ts

@@ -35,7 +35,7 @@ export async function getExperiments(
         const expPath = process.env['GEMINI_EXP'];
         debugLogger.debug('Reading experiments from', expPath);
         const content = await fs.promises.readFile(expPath, 'utf8');
-        const response = JSON.parse(content);
+        const response: ListExperimentsResponse = JSON.parse(content);
         if (
           (response.flags && !Array.isArray(response.flags)) ||
           (response.experimentIds && !Array.isArray(response.experimentIds))
@@ -44,8 +44,7 @@ export async function getExperiments(
             'Invalid format for experiments file: `flags` and `experimentIds` must be arrays if present.',
           );
         }
-        // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-        return parseExperiments(response as ListExperimentsResponse);
+        return parseExperiments(response);
       } catch (e) {
         debugLogger.debug('Failed to read experiments from GEMINI_EXP', e);
       }

packages/core/src/code_assist/oauth-credential-storage.ts

@@ -125,8 +125,7 @@ export class OAuthCredentialStorage {
       throw error;
     }
 
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-    const credentials = JSON.parse(credsJson) as Credentials;
+    const credentials: Credentials = JSON.parse(credsJson);
 
     // Save to new storage
     await this.saveCredentials(credentials);

packages/core/src/code_assist/oauth2.ts

@@ -115,9 +115,9 @@ async function initOauthClient(
 
   if (
     credentials &&
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-    (credentials as { type?: string }).type ===
-      'external_account_authorized_user'
+    typeof credentials === 'object' &&
+    'type' in credentials &&
+    credentials.type === 'external_account_authorized_user'
   ) {
     const auth = new GoogleAuth({
       scopes: OAUTH_SCOPE,
@@ -603,9 +603,10 @@ export function getAvailablePort(): Promise<number> {
       }
       const server = net.createServer();
       server.listen(0, () => {
-        // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-        const address = server.address()! as net.AddressInfo;
-        port = address.port;
+        const address = server.address();
+        if (address && typeof address === 'object') {
+          port = address.port;
+        }
       });
       server.on('listening', () => {
         server.close();

packages/core/src/code_assist/server.ts

@@ -7,7 +7,6 @@
 import type { AuthClient } from 'google-auth-library';
 import type {
   CodeAssistGlobalUserSettingResponse,
-  GoogleRpcResponse,
   LoadCodeAssistRequest,
   LoadCodeAssistResponse,
   LongRunningOperationResponse,
@@ -296,7 +295,7 @@ export class CodeAssistServer implements ContentGenerator {
     req: object,
     signal?: AbortSignal,
   ): Promise<T> {
-    const res = await this.client.request({
+    const res = await this.client.request<T>({
       url: this.getMethodUrl(method),
       method: 'POST',
       headers: {
@@ -307,15 +306,14 @@ export class CodeAssistServer implements ContentGenerator {
       body: JSON.stringify(req),
       signal,
     });
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-    return res.data as T;
+    return res.data;
   }
 
   private async makeGetRequest<T>(
     url: string,
     signal?: AbortSignal,
   ): Promise<T> {
-    const res = await this.client.request({
+    const res = await this.client.request<T>({
       url,
       method: 'GET',
       headers: {
@@ -325,8 +323,7 @@ export class CodeAssistServer implements ContentGenerator {
       responseType: 'json',
       signal,
     });
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-    return res.data as T;
+    return res.data;
   }
 
   async requestGet<T>(method: string, signal?: AbortSignal): Promise<T> {
@@ -371,8 +368,7 @@ export class CodeAssistServer implements ContentGenerator {
           if (bufferedLines.length === 0) {
             continue; // no data to yield
           }
-          // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-          yield JSON.parse(bufferedLines.join('\n')) as T;
+          yield JSON.parse(bufferedLines.join('\n'));
           bufferedLines = []; // Reset the buffer after yielding
         }
         // Ignore other lines like comments or id fields
@@ -397,23 +393,43 @@ export class CodeAssistServer implements ContentGenerator {
   }
 }
 
-function isVpcScAffectedUser(error: unknown): boolean {
-  if (error && typeof error === 'object' && 'response' in error) {
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-    const gaxiosError = error as {
-      response?: {
-        data?: unknown;
+interface VpcScErrorResponse {
+  response: {
+    data: {
+      error: {
+        details: unknown[];
       };
     };
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-    const response = gaxiosError.response?.data as
-      | GoogleRpcResponse
-      | undefined;
-    if (Array.isArray(response?.error?.details)) {
-      return response.error.details.some(
-        (detail) => detail.reason === 'SECURITY_POLICY_VIOLATED',
-      );
-    }
+  };
+}
+
+function isVpcScErrorResponse(error: unknown): error is VpcScErrorResponse {
+  return (
+    !!error &&
+    typeof error === 'object' &&
+    'response' in error &&
+    !!error.response &&
+    typeof error.response === 'object' &&
+    'data' in error.response &&
+    !!error.response.data &&
+    typeof error.response.data === 'object' &&
+    'error' in error.response.data &&
+    !!error.response.data.error &&
+    typeof error.response.data.error === 'object' &&
+    'details' in error.response.data.error &&
+    Array.isArray(error.response.data.error.details)
+  );
+}
+
+function isVpcScAffectedUser(error: unknown): boolean {
+  if (isVpcScErrorResponse(error)) {
+    return error.response.data.error.details.some(
+      (detail: unknown) =>
+        detail &&
+        typeof detail === 'object' &&
+        'reason' in detail &&
+        detail.reason === 'SECURITY_POLICY_VIOLATED',
+    );
   }
   return false;
 }