Merge pull request #5 from SiddharthShyniben/next

Allow regex interpolation

src/__tests__/index.test.ts

@@ -11,6 +11,13 @@ it('should build regexes properly', () => {
 		\s+
 	`).toStrictEqual(/\d+\s+/);
 
+	expect(regex`
+		// Here's an interpolation
+		${/\d+\s/g}
+		/* Here's a nested regex call */
+		${regex`.*`}
+	`).toStrictEqual(/\d+\s.*/);
+
 	expect(regex`
 		// Here's an interpolation
 
@@ -54,5 +61,5 @@ it('should build regexes properly', () => {
 			May not match everything because extensions are (mostly) letters
 		*/
 		[a-z0-9](?:[a-z0-9-]*[a-z0-9])?
-	${'g'}`).toStrictEqual(/[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z\d!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z\d](?:[a-z\d-]*[a-z\d])?\.)+[a-z\d](?:[a-z\d-]*[a-z\d])?/g);
+	${'g'}`).toStrictEqual(/[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?/g);
 });

src/index.ts

@@ -20,11 +20,11 @@
  */
 
 /**
- * Clean a string (remove comments, whitespace, extra stuff in other template literals and such)
+ * Clean a string (remove comments, whitespace, etc.)
  * @param piece the string to clean
- * @returns string
+ * @returns {string} th cleaned string
  */
-export function clean(piece: string) {
+export function clean(piece: string): string {
 	// Funny how we don't use our own functions to build our own regexes
 	return piece
 		// Get rid of any escaped (`) tildes
@@ -37,13 +37,28 @@ export function clean(piece: string) {
 		.replace(/\n\s*/g, '');
 }
 
-export function regex({raw}: TemplateStringsArray, ...interpolations: string[]) {
-	const flags: string | undefined = raw[raw.length - 1] ? undefined : interpolations.pop();
+/**
+ * Parse an object to make it embeddable within an object
+ * @param interpol the interpolation to parse5
+ * @returns {string} The stringified regex
+ */
+function parse(interpol: any): string {
+	return interpol instanceof RegExp ? interpol.source : [interpol].join();
+}
+
+/**
+ * Convert a string to a regex
+ * @param param0 The template strings array
+ * @param interpolations the interpolations
+ * @returns {RegExp} The parsed regex
+ */
+export function regex({raw}: TemplateStringsArray, ...interpolations: any[]): RegExp {
+	const flags = raw[raw.length - 1] ? '' : parse(interpolations.pop());
 	/* eslint-disable-next-line unicorn/no-array-reduce */
 	return new RegExp(interpolations.reduce(
 		(regexp, insert, index) => {
-			return `${regexp}${insert}${clean(raw[index + 1])}`;
+			return `${parse(regexp)}${parse(insert)}${clean(raw[index + 1])}`;
 		},
 		clean(raw[0])
-	), flags);
+	) as string, flags);
 }