Refactor: Eliminate no-unsafe-return suppressions via strict type validation (#20668)

Signed-off-by: M-DEV-1 <mahadevankizhakkedathu@gmail.com>
Co-authored-by: Tommaso Sciortino <sciortino@gmail.com>

packages/cli/src/utils/envVarResolver.ts

@@ -111,18 +111,20 @@ function resolveEnvVarsInObjectInternal<T>(
     // Check for circular reference
     if (visited.has(obj)) {
       // Return a shallow copy to break the cycle
-      // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-      return [...obj] as unknown as T;
+      const copy: unknown = [...obj];
+      const isTArray = (val: unknown): val is T => Array.isArray(val);
+      if (isTArray(copy)) return copy;
+      throw new Error('Unreachable');
     }
 
     visited.add(obj);
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-    const result = obj.map((item) =>
-      // eslint-disable-next-line @typescript-eslint/no-unsafe-return
+    const mapped: unknown = obj.map((item: unknown) =>
       resolveEnvVarsInObjectInternal(item, visited, customEnv),
-    ) as unknown as T;
+    );
     visited.delete(obj);
-    return result;
+    const isTArray = (val: unknown): val is T => Array.isArray(val);
+    if (isTArray(mapped)) return mapped;
+    throw new Error('Unreachable');
   }
 
   if (typeof obj === 'object') {

packages/cli/src/utils/gitUtils.ts

@@ -83,8 +83,7 @@ export const getLatestGitHubRelease = async (
     if (!releaseTag) {
       throw new Error(`Response did not include tag_name field`);
     }
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-return
-    return releaseTag;
+    return typeof releaseTag === 'string' ? releaseTag : '';
   } catch (error) {
     debugLogger.debug(
       `Failed to determine latest run-gemini-cli release:`,

packages/cli/src/utils/jsonoutput.ts

@@ -29,8 +29,7 @@ export function tryParseJSON(input: string): object | null {
   if (!checkInput(input)) return null;
   const trimmed = input.trim();
   try {
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
-    const parsed = JSON.parse(trimmed);
+    const parsed: unknown = JSON.parse(trimmed);
     if (parsed === null || typeof parsed !== 'object') {
       return null;
     }
@@ -40,7 +39,6 @@ export function tryParseJSON(input: string): object | null {
 
     if (!Array.isArray(parsed) && Object.keys(parsed).length === 0) return null;
 
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-return
     return parsed;
   } catch {
     return null;