From 17028a3f86f97b9d2ea3a0d31346ed62885f65c3 Mon Sep 17 00:00:00 2001
From: dodococo <deepakchethan@outlook.com>
Date: Wed, 7 Oct 2020 12:03:53 +0530
Subject: [PATCH] Input Widget: Parse regexp before regex validation (#884)

Fixes #697
---
 app/client/src/widgets/InputWidget.tsx | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/app/client/src/widgets/InputWidget.tsx b/app/client/src/widgets/InputWidget.tsx
index c260a1fc7d..2c8a35ce23 100644
--- a/app/client/src/widgets/InputWidget.tsx
+++ b/app/client/src/widgets/InputWidget.tsx
@@ -51,6 +51,21 @@ class InputWidget extends BaseWidget<InputWidgetProps, WidgetState> {
     return {
       isValid: `{{
         function(){
+          let parsedRegex = null;
+          if (this.regex) {
+            // break up the regexp pattern into 4 parts: given regex, regex prefix , regex pattern, regex flags
+            // Example /appsmith/i will be split into ["/appsmith/gi", "/", "appsmith", "gi"]
+            const regexParts = this.regex.match(/(\\/?)(.+)\\1([a-z]*)/i);
+            if (regexParts === null) {
+              parsedRegex = new RegExp(this.regex);
+            }
+            // if we don't have a regex flags (gmisuy), convert provided string into regexp directly
+            if (regexParts[3] && !/^(?!.*?(.).*?\\1)[gmisuy]+$/.test(regexParts[3])) {
+              parsedRegex = RegExp(this.regex);
+            }
+            // if we have a regex flags, use it to form regexp
+            parsedRegex = new RegExp(regexParts[2], regexParts[3]);
+          }
           if (this.inputType === "EMAIL") {
             const emailRegex = new RegExp(/^\\w+([\\.-]?\\w+)*@\\w+([\\.-]?\\w+)*(\\.\\w{2,3})+$/);
             return emailRegex.test(this.text);
@@ -60,16 +75,16 @@ class InputWidget extends BaseWidget<InputWidgetProps, WidgetState> {
           }
           else if (this.isRequired) {
             if(this.text && this.text.length) {
-              if(this.regex) {
-                return new RegExp(this.regex).test(this.text)
+              if (parsedRegex) {
+                return parsedRegex.test(this.text)
               } else {
                 return true;
               }
             } else {
               return false;
             }
-          } if (this.regex) {
-            return new RegExp(this.regex).test(this.text)
+          } if (parsedRegex) {
+            return parsedRegex.test(this.text)
           } else {
             return true;
           }