test: support phpunit-9

Updated the PhpUnitCompat compatibility layer to support both
expectExceptionMessageMatches() method on phpunit-6 and phpunit-7/

See the phpunit-9 announcement [1], where expectExceptionMessageRegExp()
method removal was announced.

We're going to use phpunit-9 for testing the connector on PHP 7.3 and
PHP 7.4.

[1]: https://phpunit.de/announcements/phpunit-9.html

Author: Totktonada

test/CreateTest.php

@@ -51,7 +51,7 @@ public function test_02_create_error_host() {
 			$c = new Tarantool('very_bad_host');
 
 			$this->expectException(TarantoolException::class);
-			$this->expectExceptionMessageRegExp(
+			$this->expectExceptionMessageMatches(
 				'/Name or service not known' .
 				'|nodename nor servname provided' .
 				'|Temporary failure in name resolution/');
@@ -62,7 +62,7 @@ public function test_03_00_create_error_port() {
 			$c = new Tarantool('127.0.0.1', 65500);
 
 			$this->expectException(TarantoolException::class);
-			$this->expectExceptionMessageRegExp(
+			$this->expectExceptionMessageMatches(
 				'/Connection refused|Network is unreachable/');
 			$c->connect();
 		}

test/PhpUnitCompat.php

@@ -7,12 +7,13 @@
  * different phpunit versions (phpunit-6 and phpunit-7 at the
  * moment).
  *
- * Now it contains workarounds for two problems:
+ * Now it contains workarounds for the following problems:
  *
  * - phpunit-7 requirement to use `void` return type declaration
  *   for several methods.
  * - phpunit-8 deprecation warning re using assertContains() for
  *   search a substring in a string.
+ * - phpunit-9 removes expectExceptionMessageRegExp() method.
  *
  * Usage: add `use TestCaseCompat;` in a TestCase derived class
  * and follow instructions and examples below.
@@ -74,6 +75,13 @@
  * substring in a string. Add `use TestCaseCompat;` to a TestCase
  * derived class and use assertStringContainsString() on any
  * phpunit-6+ version.
+ *
+ * expectExceptionMessageRegExp() removal
+ * --------------------------------------
+ *
+ * phpunit-8 and newer provides the same function under
+ * expectExceptionMessageMatches() name. phpunit-9 removes the old
+ * expectExceptionMessageRegExp() alias.
  */
 
 use PHPUnit\Framework\TestCase;
@@ -200,6 +208,28 @@ public static function assertStringContainsString(
     }
 }
 
+/*
+ * ExpectExceptionMessageMatchesTrait (private).
+ *
+ * phpunit-8 provides the new name for
+ * expectExceptionMessageRegExp() method:
+ * expectExceptionMessageMatches(). phpunit-9 removes the old name.
+ *
+ * This trait adds expectExceptionMessageMatches() method for
+ * phpunit-6 and phpunit-7.
+ */
+if ($testCaseRef->hasMethod('expectExceptionMessageMatches')) {
+    trait ExpectExceptionMessageMatchesTrait {
+        /* Nothing to define. */
+    }
+} else {
+    trait ExpectExceptionMessageMatchesTrait {
+        public function expectExceptionMessageMatches($regularExpression) {
+            self::expectExceptionMessageRegExp($regularExpression);
+        }
+    }
+}
+
 /*
  * TestCaseCompat (public).
  *
@@ -209,4 +239,5 @@ trait TestCaseCompat
 {
     use SetUpTearDownTrait;
     use AssertStringContainsStringTrait;
+    use ExpectExceptionMessageMatchesTrait;
 }