Backport JSON funcs from v2

tests/Integration/PostgreSQL/CustomTest.php

@@ -65,6 +65,30 @@ describe('::array()', function () {
     });
 });
 
+describe('::jsonArray()', function () {
+    test('returns non-empty array when data found', function () {
+        expect(Custom::jsonArray(Query::selectFromTable(ThrowawayDb::TABLE) . " WHERE data->>'sub' IS NOT NULL", []))
+            ->toContain('[{', '},{', '}]');
+    });
+    test('returns empty array when no data found', function () {
+        expect(Custom::jsonArray(Query::selectFromTable(ThrowawayDb::TABLE) . " WHERE data->>'nothing' = '7'", []))
+            ->toBe('[]');
+    });
+});
+
+describe('::outputJsonArray()', function () {
+    test('outputs non-empty array when data found', function () {
+        $this->clearBuffer();
+        Custom::outputJsonArray(Query::selectFromTable(ThrowawayDb::TABLE) . " WHERE data->>'sub' IS NOT NULL", []);
+        expect($this->getBufferContents())->toContain('[{', '},{', '}]');
+    });
+    test('outputs empty array when no data found', function () {
+        $this->clearBuffer();
+        Custom::outputJsonArray(Query::selectFromTable(ThrowawayDb::TABLE) . " WHERE data->>'nothing' = '7'", []);
+        expect($this->getBufferContents())->toBe('[]');
+    });
+});
+
 describe('::single()', function () {
     test('returns a document when one is found', function () {
         expect(Custom::single('SELECT data FROM ' . ThrowawayDb::TABLE . " WHERE data->>'id' = :id", [':id' => 'one'],
@@ -79,6 +103,19 @@ describe('::single()', function () {
     });
 });
 
+describe('::jsonSingle()', function () {
+    test('returns a document when one is found', function () {
+        expect(Custom::jsonSingle('SELECT data FROM ' . ThrowawayDb::TABLE . " WHERE data->>'id' = :id",
+            [':id' => 'one']))
+            ->toStartWith('{"id":')->toContain('"one",')->toEndWith('}');
+    });
+    test('returns no document when one is not found', function () {
+        expect(Custom::jsonSingle('SELECT data FROM ' . ThrowawayDb::TABLE . " WHERE data->>'id' = :id",
+            [':id' => 'eighty']))
+            ->toBe('{}');
+    });
+});
+
 describe('::nonQuery()', function () {
     test('works when documents match the WHERE clause', function () {
         Custom::nonQuery('DELETE FROM ' . ThrowawayDb::TABLE, []);