flow like the river

BACK_BACK/node_modules/bson/src/regexp.ts

@@ -0,0 +1,114 @@
+import { BSONValue } from './bson_value';
+import { BSONError } from './error';
+import type { EJSONOptions } from './extended_json';
+
+function alphabetize(str: string): string {
+  return str.split('').sort().join('');
+}
+
+/** @public */
+export interface BSONRegExpExtendedLegacy {
+  $regex: string | BSONRegExp;
+  $options: string;
+}
+
+/** @public */
+export interface BSONRegExpExtended {
+  $regularExpression: {
+    pattern: string;
+    options: string;
+  };
+}
+
+/**
+ * A class representation of the BSON RegExp type.
+ * @public
+ * @category BSONType
+ */
+export class BSONRegExp extends BSONValue {
+  get _bsontype(): 'BSONRegExp' {
+    return 'BSONRegExp';
+  }
+
+  pattern!: string;
+  options!: string;
+  /**
+   * @param pattern - The regular expression pattern to match
+   * @param options - The regular expression options
+   */
+  constructor(pattern: string, options?: string) {
+    super();
+    this.pattern = pattern;
+    this.options = alphabetize(options ?? '');
+
+    if (this.pattern.indexOf('\x00') !== -1) {
+      throw new BSONError(
+        `BSON Regex patterns cannot contain null bytes, found: ${JSON.stringify(this.pattern)}`
+      );
+    }
+    if (this.options.indexOf('\x00') !== -1) {
+      throw new BSONError(
+        `BSON Regex options cannot contain null bytes, found: ${JSON.stringify(this.options)}`
+      );
+    }
+
+    // Validate options
+    for (let i = 0; i < this.options.length; i++) {
+      if (
+        !(
+          this.options[i] === 'i' ||
+          this.options[i] === 'm' ||
+          this.options[i] === 'x' ||
+          this.options[i] === 'l' ||
+          this.options[i] === 's' ||
+          this.options[i] === 'u'
+        )
+      ) {
+        throw new BSONError(`The regular expression option [${this.options[i]}] is not supported`);
+      }
+    }
+  }
+
+  static parseOptions(options?: string): string {
+    return options ? options.split('').sort().join('') : '';
+  }
+
+  /** @internal */
+  toExtendedJSON(options?: EJSONOptions): BSONRegExpExtendedLegacy | BSONRegExpExtended {
+    options = options || {};
+    if (options.legacy) {
+      return { $regex: this.pattern, $options: this.options };
+    }
+    return { $regularExpression: { pattern: this.pattern, options: this.options } };
+  }
+
+  /** @internal */
+  static fromExtendedJSON(doc: BSONRegExpExtendedLegacy | BSONRegExpExtended): BSONRegExp {
+    if ('$regex' in doc) {
+      if (typeof doc.$regex !== 'string') {
+        // This is for $regex query operators that have extended json values.
+        if (doc.$regex._bsontype === 'BSONRegExp') {
+          return doc as unknown as BSONRegExp;
+        }
+      } else {
+        return new BSONRegExp(doc.$regex, BSONRegExp.parseOptions(doc.$options));
+      }
+    }
+    if ('$regularExpression' in doc) {
+      return new BSONRegExp(
+        doc.$regularExpression.pattern,
+        BSONRegExp.parseOptions(doc.$regularExpression.options)
+      );
+    }
+    throw new BSONError(`Unexpected BSONRegExp EJSON object form: ${JSON.stringify(doc)}`);
+  }
+
+  /** @internal */
+  [Symbol.for('nodejs.util.inspect.custom')](): string {
+    return this.inspect();
+  }
+
+  inspect(): string {
+    return `new BSONRegExp(${JSON.stringify(this.pattern)}, ${JSON.stringify(this.options)})`;
+  }
+}