更新

server/tests/DifyChatStreamContractTest.php

@@ -172,6 +172,31 @@ difyStreamExpect($decodedOpenAi['content'] === 'A中', 'OpenAI decoder handles a
 difyStreamExpect($decodedOpenAi['deltas'] === ['A', '中'], 'OpenAI decoder emits choices delta content only');
 difyStreamExpect($decodedOpenAi['finished'] === true, 'OpenAI [DONE] terminates parsing');
 
+$pendingBuffer = '';
+$pendingState = callDifyStreamPrivate('newStreamState', []);
+$liveDeltas = [];
+$liveCallback = static function (string $delta) use (&$liveDeltas): void {
+    $liveDeltas[] = $delta;
+};
+callDifyStreamPrivate('consumeStreamBytes', [
+    'dify', &$pendingBuffer, "data: {\"event\":\"message\",\"answer\":\"首字\"}\r\n", &$pendingState, $liveCallback,
+]);
+difyStreamExpect($liveDeltas === [], 'a data line alone is not a complete SSE event');
+callDifyStreamPrivate('consumeStreamBytes', ['dify', &$pendingBuffer, "\r\n", &$pendingState, $liveCallback]);
+difyStreamExpect($liveDeltas === ['首字'], 'a complete delta is delivered before upstream EOF or a terminal event');
+difyStreamExpect($pendingState['finished'] === false, 'incremental delivery does not wait for message_end');
+
+$multilineWire = "data: {\"event\":\"message\",\r\n"
+    . "data: \"answer\":\"逐帧\"}\r\n\r\n"
+    . "data: {\"event\":\"message_end\"}\r\n\r\n";
+foreach ([1, 2, strlen($multilineWire)] as $chunkSize) {
+    $multiline = callDifyStreamPrivate('decodeStreamChunks', ['dify', str_split($multilineWire, $chunkSize)]);
+    difyStreamExpect(
+        $multiline['deltas'] === ['逐帧'] && $multiline['finished'] === true,
+        'CRLF multiline data stays one event across arbitrary transport boundaries'
+    );
+}
+
 $malformed = callDifyStreamPrivate('decodeStreamChunks', [
     'dify',
     ["data: not-json\n\n", "data: {\"event\":\"error\",\"message\":\"secret-upstream-body\"}\n\n"],