feat(Match): Implement match

Returns a list of valid postcodes within a body of text

Author: cblanc

lib/index.ts

@@ -19,6 +19,11 @@ export const OUTCODE_REGEX = /^[a-z]{1,2}\d[a-z\d]?$/i;
  */
 export const POSTCODE_REGEX = /^[a-z]{1,2}\d[a-z\d]?\s*\d[a-z]{2}$/i;
 
+/**
+ * Test for a valid postcode embedded in text
+ */
+export const POSTCODE_CORPUS_REGEX = /[a-z]{1,2}\d[a-z\d]?\s*\d[a-z]{2}/gi;
+
 /**
  * Tests for the area section of a postcode
  */
@@ -283,3 +288,11 @@ export const parse = (postcode: string): ValidPostcode | InvalidPostcode => {
     unit: toUnit(postcode) as string,
   };
 };
+
+/**
+ * Searches a body of text for postcode matches
+ *
+ * Returns an empty array if no match
+ */
+export const match = (corpus: string): string[] =>
+  corpus.match(POSTCODE_CORPUS_REGEX) || [];

test/unit.ts

@@ -2,6 +2,8 @@ import { assert } from "chai";
 import * as Postcode from "../lib/index";
 import { loadFixtures, TestMethod } from "./util/helper";
 
+const { match } = Postcode;
+
 const testMethod: TestMethod = (options) => {
   const { tests, method } = options;
   tests.forEach(({ base, expected }) => {
@@ -123,3 +125,15 @@ describe("Unit parsing", () => {
     assert.isNull(Postcode.parse("Definitely bogus").unit);
   });
 });
+
+describe("match", () => {
+  it("returns matching postcodes", () => {
+    const corpus = `SW1A2Aa is the residence of the Prime Minister. SW1a 2AB is the residence of her no.2. SW1A   1AA is where the queen lives. They are located in the SW1A outcode`;
+    assert.deepEqual(match(corpus), ["SW1A2Aa", "SW1a 2AB", "SW1A   1AA"]);
+  });
+
+  it("returns an empty array if no match", () => {
+    const corpus = `SW1 NW1 E1 E2`;
+    assert.deepEqual(match(corpus), []);
+  });
+});