add: support configuration of regex flags in schema and globally

Author: sagold

README.md

@@ -1336,6 +1336,26 @@ const { errors } = compileSchema({
 assert.deepEqual(errors[0].message, "Custom error 2");
 ```
 
+### regexFlags
+
+In order to allow customization of regular expressions a schema property `regexFlags` is supported for `pattern`, `patternProperties` and format `regex`:
+
+```ts
+const { errors } = compileSchema({
+    type: "string",
+    pattern: "^[a-zA-Z0-9+_.\-]+"
+    regexFlags: "v"
+}).validate("-");
+```
+
+Per default, a regexFlags `"u"` is used. To change this setting globally, change `REGEX_FLAGS` in settings:
+
+```ts
+import settings from "json-schema-library";
+
+settings.REGEX_FLAGS = "v";
+```
+
 ## Breaking Changes
 
 ### v10.1.0

src/SchemaNode.ts

@@ -19,7 +19,7 @@ import { hasProperty } from "./utils/hasProperty";
 import { getNode } from "./getNode";
 import { getNodeChild } from "./getNodeChild";
 
-const { DYNAMIC_PROPERTIES } = settings;
+const { DYNAMIC_PROPERTIES, REGEX_FLAGS } = settings;
 
 export function isSchemaNode(value: unknown): value is SchemaNode {
     return isObject(value) && Array.isArray(value?.reducers) && Array.isArray(value?.resolvers);
@@ -42,7 +42,7 @@ function getDraft(drafts: Draft[], $schema: string) {
     if (drafts.length === 1) {
         return drafts[0];
     }
-    return drafts.find((d) => new RegExp(d.$schemaRegEx).test($schema)) ?? drafts[drafts.length - 1];
+    return drafts.find((d) => new RegExp(d.$schemaRegEx, REGEX_FLAGS).test($schema)) ?? drafts[drafts.length - 1];
 }
 
 export type Context = {

src/compileSchema.ts

@@ -9,6 +9,9 @@ import { pick } from "./utils/pick";
 import { JsonSchema, Draft } from "./types";
 import { TemplateOptions } from "./methods/getData";
 import { SchemaNode, SchemaNodeMethods, addKeywords, isSchemaNode } from "./SchemaNode";
+import settings from "./settings";
+
+const { REGEX_FLAGS } = settings;
 
 export type CompileOptions = {
     drafts?: Draft[];
@@ -20,7 +23,7 @@ export type CompileOptions = {
 const defaultDrafts: Draft[] = [draft04, draft06, draft07, draft2019, draft2020];
 
 function getDraft(drafts: Draft[], $schema: string) {
-    return drafts.find((d) => new RegExp(d.$schemaRegEx).test($schema)) ?? drafts[drafts.length - 1];
+    return drafts.find((d) => new RegExp(d.$schemaRegEx, REGEX_FLAGS).test($schema)) ?? drafts[drafts.length - 1];
 }
 
 /**

src/formats/formats.ts

@@ -4,7 +4,9 @@ import validUrl from "valid-url";
 import { JsonSchemaValidatorParams, ValidationResult } from "../Keyword";
 import { parse as parseIdnEmail } from "smtp-address-parser";
 import { JsonError } from "../types";
+import settings from "../settings";
 
+const { REGEX_FLAGS } = settings;
 const isValidIPV4 = /^(?:(?:25[0-5]|2[0-4]\d|[01]?\d\d?)\.){3}(?:25[0-5]|2[0-4]\d|[01]?\d\d?)$/;
 const isValidIPV6 =
     /^((([0-9a-f]{1,4}:){7}([0-9a-f]{1,4}|:))|(([0-9a-f]{1,4}:){6}(:[0-9a-f]{1,4}|((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9a-f]{1,4}:){5}(((:[0-9a-f]{1,4}){1,2})|:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9a-f]{1,4}:){4}(((:[0-9a-f]{1,4}){1,3})|((:[0-9a-f]{1,4})?:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9a-f]{1,4}:){3}(((:[0-9a-f]{1,4}){1,4})|((:[0-9a-f]{1,4}){0,2}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9a-f]{1,4}:){2}(((:[0-9a-f]{1,4}){1,5})|((:[0-9a-f]{1,4}){0,3}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9a-f]{1,4}:){1}(((:[0-9a-f]{1,4}){1,6})|((:[0-9a-f]{1,4}){0,4}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(:(((:[0-9a-f]{1,4}){1,7})|((:[0-9a-f]{1,4}){0,5}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:)))$/i;
@@ -223,7 +225,7 @@ export const formats: Record<
         }
         if (typeof data === "string" && /\\Z$/.test(data) === false) {
             try {
-                new RegExp(data, "u");
+                new RegExp(data, schema.regexFlags ?? REGEX_FLAGS);
                 return undefined;
             } catch (e) {} // eslint-disable-line no-empty
 

src/keywords/pattern.ts

@@ -1,4 +1,7 @@
 import { Keyword, JsonSchemaValidatorParams } from "../Keyword";
+import settings from "../settings";
+
+const { REGEX_FLAGS } = settings;
 
 export const patternKeyword: Keyword = {
     id: "pattern",
@@ -12,7 +15,7 @@ function validatePattern({ node, data, pointer = "#" }: JsonSchemaValidatorParam
     if (typeof data !== "string") {
         return;
     }
-    const pattern = new RegExp(schema.pattern, "u");
+    const pattern = new RegExp(schema.pattern, schema.regexFlags ?? REGEX_FLAGS);
     if (pattern.test(data) === false) {
         return node.createError("pattern-error", {
             pattern: schema.pattern,

src/keywords/patternProperties.ts

@@ -10,6 +10,9 @@ import {
 } from "../Keyword";
 import { getValue } from "../utils/getValue";
 import { validateNode } from "../validateNode";
+import settings from "../settings";
+
+const { REGEX_FLAGS } = settings;
 
 export const patternPropertiesKeyword: Keyword = {
     id: "patternProperties",
@@ -32,9 +35,10 @@ export function parsePatternProperties(node: SchemaNode) {
     if (patterns.length === 0) {
         return;
     }
+
     node.patternProperties = patterns.map((pattern) => ({
         name: pattern,
-        pattern: new RegExp(pattern, "u"),
+        pattern: new RegExp(pattern, schema.regexFlags ?? REGEX_FLAGS),
         node: node.compileSchema(
             schema.patternProperties[pattern],
             `${node.evaluationPath}/patternProperties/${pattern}`,

src/settings.ts

@@ -15,5 +15,6 @@ export default {
         "definitions",
         "dependencies",
         "patternProperties"
-    ]
+    ],
+    REGEX_FLAGS: "u"
 };