Add URL lookup by link label in a given email

README.md

@@ -246,6 +246,36 @@ For `<a href="http://second-link.com">Second link</a>`, this returns
 
 * Param $label
 
+### grabUrlForLinkFromEmail
+
+Returns the `href` of the first link whose text exactly matches the label in
+the given email's HTML body. Matching is case-sensitive. Nested tags and HTML
+entities are decoded. Whitespace in the label is preserved.
+
+Fails if the email has no HTML body or no matching link with an `href`.
+
+Example:
+
+```php
+$email = $I->lastMessageTo('user@example.com');
+$url = $I->grabUrlForLinkFromEmail($email, 'Second link');
+```
+
+To use the last email:
+
+```php
+$url = $I->grabUrlForLinkFromEmail($I->lastMessage(), 'Second link');
+```
+
+For `<a href="http://second-link.com">Second link</a>`, this returns
+`http://second-link.com`.
+
+Use an `Email` object from `lastMessage()`, `lastMessageTo()`, or
+`lastMessageFrom()`, or one you created directly.
+
+* Param $email
+* Param $label
+
 ### lastMessageFrom
 
 Grab the full email object sent to an address.

src/Module/MailCatcher.php

@@ -392,7 +392,16 @@ public function grabUrlsFromNthEmail(int $nth): array
      */
     public function grabUrlForLinkFromLastEmail(string $label): string
     {
-        $message = Message::from($this->lastMessage()->getSource(), false);
+        return $this->grabUrlForLinkFromEmail($this->lastMessage(), $label);
+    }
+
+    /**
+     * Return the URL of the first link with an exact, case-sensitive label
+     * in the given email's HTML body. Fail if no matching link has an href.
+     */
+    public function grabUrlForLinkFromEmail(Email $email, string $label): string
+    {
+        $message = Message::from($email->getSource(), false);
         $html = $message->getHtmlContent();
 
         if ($html !== null && $html !== '') {

tests/unit/Module/MailCatcherTest.php

@@ -222,19 +222,48 @@ public function testGrabUrlForLinkFromLastEmail()
         $this->assertSame('http://second-link.com', $mailcatcher->grabUrlForLinkFromLastEmail('Second link'));
     }
 
+    public function testGrabUrlForLinkFromEmail()
+    {
+        $mailcatcher = new MailCatcherTest_TestClass();
+        $email = new Email(1, [], '',
+            "Content-Type: text/html; charset=UTF-8\r\n\r\n"
+            . '<a href="http://first-link.com">First link</a>'
+            . '<a href="http://second-link.com">Second link</a>'
+        );
+
+        $this->assertSame('http://second-link.com', $mailcatcher->grabUrlForLinkFromEmail($email, 'Second link'));
+    }
+
+    public function testGrabUrlForLinkFromGivenEmail()
+    {
+        $mailcatcher = new MailCatcherTest_TestClass();
+        $mailcatcher->setLastMessage(new Email(2, [], '',
+            "Content-Type: text/html; charset=UTF-8\r\n\r\n"
+            . '<a href="https://example.com/latest">Reset password</a>'
+        ));
+        $email = new Email(1, ['user@example.com'], '',
+            "Content-Type: text/html; charset=UTF-8\r\n\r\n"
+            . '<a href="https://example.com/selected">Reset password</a>'
+        );
+
+        $this->assertSame('https://example.com/selected', $mailcatcher->grabUrlForLinkFromEmail($email, 'Reset password'));
+    }
+
     public function testGrabUrlForLinkFromEncodedHtmlEmail()
     {
         $html = '<a href="https://example.com/first?one=1&amp;two=2"><strong>Café &amp; "tea"</strong></a>'
             . '<a href="https://example.com/second">Café &amp; "tea"</a>';
         $mailcatcher = new MailCatcherTest_TestClass();
-        $mailcatcher->setLastMessage(new Email(1, [], '',
+        $email = new Email(1, [], '',
             "MIME-Version: 1.0\r\nContent-Type: multipart/alternative; boundary=parts\r\n\r\n"
             . "--parts\r\nContent-Type: text/plain; charset=UTF-8\r\n\r\nPlain text\r\n"
             . "--parts\r\nContent-Type: text/html; charset=UTF-8\r\n"
             . "Content-Transfer-Encoding: quoted-printable\r\n\r\n"
             . quoted_printable_encode($html) . "\r\n--parts--\r\n"
-        ));
+        );
 
+        $this->assertSame('https://example.com/first?one=1&two=2', $mailcatcher->grabUrlForLinkFromEmail($email, 'Café & "tea"'));
+        $mailcatcher->setLastMessage($email);
         $this->assertSame('https://example.com/first?one=1&two=2', $mailcatcher->grabUrlForLinkFromLastEmail('Café & "tea"'));
     }
 
@@ -252,6 +281,20 @@ public function testGrabUrlForLinkFromLastEmailFailsWhenNoLinkMatches(string $so
         $mailcatcher->grabUrlForLinkFromLastEmail('Second link');
     }
 
+    /**
+     * @dataProvider missingLinkEmails
+     */
+    public function testGrabUrlForLinkFromEmailFailsWhenNoLinkMatches(string $source)
+    {
+        $mailcatcher = new MailCatcherTest_TestClass();
+        $email = new Email(1, [], '', $source);
+
+        $this->expectException(AssertionFailedError::class);
+        $this->expectExceptionMessage('No link found with label: Second link');
+
+        $mailcatcher->grabUrlForLinkFromEmail($email, 'Second link');
+    }
+
     public static function missingLinkEmails(): array
     {
         return [