Merge pull request #27917 from SimonSchick/feat/joi-global-exist

fix(joi): add global exist function

types/joi/index.d.ts

@@ -1122,7 +1122,7 @@ export function ref(key: string, options?: ReferenceOptions): Reference;
 export function isRef(ref: any): ref is Reference;
 
 /**
- * Get a sub-schema of an existing schema based on a `path` that can be either a string or an array 
+ * Get a sub-schema of an existing schema based on a `path` that can be either a string or an array
  * of strings For string values path separator is a dot (`.`)
  */
 export function reach(schema: ObjectSchema, path: string): Schema;
@@ -1189,6 +1189,11 @@ export function not(values: any[]): Schema;
  */
 export function required(): Schema;
 
+/**
+ * Alias of `required`.
+ */
+export function exist(): Schema;
+
 /**
  * Marks a key as optional which will allow undefined as values. Used to annotate the schema for readability as all keys are optional by default.
  */

types/joi/joi-tests.ts

@@ -1110,6 +1110,7 @@ schema = Joi.not(x, x);
 schema = Joi.not([x, x, x]);
 
 schema = Joi.required();
+schema = Joi.exist();
 schema = Joi.optional();
 schema = Joi.forbidden();
 schema = Joi.strip();