fix(add-caching): ensure lerna.json is configured automatically

core/lerna/commands/add-caching/index.js

@@ -26,6 +26,21 @@ class AddCachingCommand extends Command {
       );
       // eslint-disable-next-line no-process-exit
       process.exit(1);
+    } // TODO: remove auto-setting useNx: true in v6
+    else if (!this.options.useNx) {
+      const lernaJsonPath = joinPathFragments(workspaceRoot, "lerna.json");
+      try {
+        const lernaJson = readJsonFile(lernaJsonPath);
+        lernaJson.useNx = true;
+        writeJsonFile(lernaJsonPath, lernaJson);
+      } catch {
+        this.logger.error(
+          "add-caching",
+          "The `add-caching` command is only available when using the Nx task runner (set `useNx` to `true` in `lerna.json`)"
+        );
+        // eslint-disable-next-line no-process-exit
+        process.exit(1);
+      }
     }
 
     const packages = this.packageGraph?.rawPackageList || [];