WIP; complete PostgreSQL integration migration

tests/Integration/PostgreSQL/ExistsTest.php

@@ -0,0 +1,48 @@
+<?php
+/**
+ * @author Daniel J. Summers <daniel@bitbadger.solutions>
+ * @license MIT
+ */
+
+declare(strict_types=1);
+
+use BitBadger\PDODocument\{Exists, Field};
+use Test\Integration\PostgreSQL\ThrowawayDb;
+
+pest()->group('integration', 'postgresql');
+
+describe('::byId()', function () {
+    test('returns true when a document exists', function () {
+        expect(Exists::byId(ThrowawayDb::TABLE, 'three'))->toBeTrue();
+    });
+    test('returns false when a document does not exist', function () {
+        expect(Exists::byId(ThrowawayDb::TABLE, 'seven'))->toBeFalse();
+    });
+});
+
+describe('::byFields()', function () {
+    test('returns true when matching documents exist', function () {
+        expect(Exists::byFields(ThrowawayDb::TABLE, [Field::equal('num_value', 10)]))->toBeTrue();
+    });
+    test('returns false when no matching documents exist', function () {
+        expect(Exists::byFields(ThrowawayDb::TABLE, [Field::less('nothing', 'none')]))->toBeFalse();
+    });
+});
+
+describe('::byContains()', function () {
+    test('returns true when matching documents exist', function () {
+        expect(Exists::byContains(ThrowawayDb::TABLE, ['value' => 'purple']))->toBeTrue();
+    });
+    test('returns false when no matching documents exist', function () {
+        expect(Exists::byContains(ThrowawayDb::TABLE, ['value' => 'violet']))->toBeFalse();
+    });
+});
+
+describe('::byJsonPath()', function () {
+    test('returns true when matching documents exist', function () {
+        expect(Exists::byJsonPath(ThrowawayDb::TABLE, '$.num_value ? (@ == 10)'))->toBeTrue();
+    });
+    test('returns false when no matching documents exist', function () {
+        expect(Exists::byJsonPath(ThrowawayDb::TABLE, '$.num_value ? (@ == 10.1)'))->toBeFalse();
+    });
+});