From 223217aea62183d90b1d6f9538cfa83c1744170d Mon Sep 17 00:00:00 2001
From: Nicolas Morel <nicolas@morel.io>
Date: Wed, 17 Jun 2026 18:50:53 +0200
Subject: [PATCH] fix: expose multiple string patterns in json schemas

---
 lib/types/string.js | 14 +++++++++++++-
 test/json-schema.js | 22 ++++++++++++++++++++++
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/lib/types/string.js b/lib/types/string.js
index 56dfe620..48303763 100755
--- a/lib/types/string.js
+++ b/lib/types/string.js
@@ -693,7 +693,19 @@ module.exports = Any.extend({
             },
             jsonSchema(rule, res) {
 
-                res.pattern = rule.args.regex.source;
+                const pattern = rule.args.regex.source;
+
+                if (res.allOf) {
+                    res.allOf.push({ pattern });
+                }
+                else if (res.pattern !== undefined) {
+                    res.allOf = [{ pattern: res.pattern }, { pattern }];
+                    delete res.pattern;
+                }
+                else {
+                    res.pattern = pattern;
+                }
+
                 return res;
             },
             args: ['regex', 'options'],
diff --git a/test/json-schema.js b/test/json-schema.js
index fe070c68..a4fdd1c2 100644
--- a/test/json-schema.js
+++ b/test/json-schema.js
@@ -1623,6 +1623,28 @@ describe('jsonSchema', () => {
             });
         });
 
+        it('composes multiple patterns via allOf', () => {
+
+            Helper.validateJsonSchema(Joi.string().pattern(/^\d+$/).pattern(/.{4,}/), {
+                type: 'string',
+                minLength: 1,
+                allOf: [
+                    { pattern: '^\\d+$' },
+                    { pattern: '.{4,}' }
+                ]
+            });
+
+            Helper.validateJsonSchema(Joi.string().pattern(/^a/).pattern(/b/).pattern(/c$/), {
+                type: 'string',
+                minLength: 1,
+                allOf: [
+                    { pattern: '^a' },
+                    { pattern: 'b' },
+                    { pattern: 'c$' }
+                ]
+            });
+        });
+
         it('represents string with valids', () => {
 
             Helper.validateJsonSchema(Joi.string().valid('a', 'b'), {