fix: explain v51 setPassword changes on command errors

messages/password.generate.json

@@ -8,7 +8,11 @@
   "flags": {
     "onBehalfOf": "comma-separated list of usernames or aliases to assign the password to"
   },
-  "noSelfSetError": "Create a scratch org with the enableSetPasswordInApi org security setting set to TRUE and try again.",
+  "noSelfSetErrorV50": "Create a scratch org with the enableSetPasswordInApi org security setting set to TRUE and try again.",
+
+  "noSelfSetError": "Beginning in version 51, enableSetPasswordInApi is a feature in your scratch org definition file.  Settings.securitySettings.passwordPolicies.enableSetPasswordInApi is deprecated.",
+  "noSelfSetErrorAction": "Update your scratch org definition file and try creating the org again",
+  "scratchFeaturesUrl": "see https://developer.salesforce.com/docs/atlas.en-us.sfdx_dev.meta/sfdx_dev/sfdx_dev_scratch_orgs_def_file_config_values.htm",
   "success": "Successfully set the password \"%s\" for user %s.",
   "successMultiple": "Successfully set passwords:%s",
   "viewWithCommand": "You can see the password again by running \"sfdx force:user:display -u %s\"."

src/commands/force/user/password/generate.ts

@@ -33,7 +33,7 @@ export class UserPasswordGenerateCommand extends SfdxCommand {
   private passwordData: PasswordData[] = [];
 
   public async run(): Promise<PasswordData[]> {
-    this.usernames = this.flags.onbehalfof ?? this.org.getUsername();
+    this.usernames = this.flags.onbehalfof ?? [this.org.getUsername()];
 
     for (const username of this.usernames) {
       try {
@@ -56,8 +56,21 @@ export class UserPasswordGenerateCommand extends SfdxCommand {
         });
         await authInfo.save();
       } catch (e) {
-        if (e.message.includes('Cannot set password for self')) {
-          throw SfdxError.create('@salesforce/plugin-user', 'password.generate', 'noSelfSetError');
+        if (
+          e.message.includes('Cannot set password for self') ||
+          e.message.includes('The requested Resource does not exist')
+        ) {
+          // we don't have access to the apiVersion from what happened in the try, so until v51 is r2, we have to check versions the hard way
+          const authInfo: AuthInfo = await AuthInfo.create({ username });
+          const connection: Connection = await Connection.create({ authInfo });
+          const org = await Org.create({ connection });
+          if (parseInt(await org.retrieveMaxApiVersion(), 10) >= 51) {
+            throw new SfdxError(messages.getMessage('noSelfSetError'), 'noSelfSetError', [
+              messages.getMessage('noSelfSetErrorAction'),
+              messages.getMessage('scratchFeaturesUrl'),
+            ]);
+          }
+          throw new SfdxError(messages.getMessage('noSelfSetErrorV50'), 'noSelfSetError');
         }
         throw SfdxError.wrap(e);
       }

test/commands/user/password/generate.test.ts

@@ -30,6 +30,7 @@ describe('force:user:password:generate', () => {
     stubMethod($$.SANDBOX, Connection, 'create').callsFake(async () => Connection.prototype);
     stubMethod($$.SANDBOX, Org, 'create').callsFake(async () => Org.prototype);
     stubMethod($$.SANDBOX, Org.prototype, 'getUsername').returns('[email protected]');
+    stubMethod($$.SANDBOX, Org.prototype, 'retrieveMaxApiVersion').returns('51.0');
     stubMethod($$.SANDBOX, User, 'create').callsFake(async () => User.prototype);
     stubMethod($$.SANDBOX, User.prototype, 'retrieve').resolves({
       id: '0052D0000043PawWWR',