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fix: parse built-in repl prompts instead of faulty custom markers #55

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fix: parse built-in repl prompts instead of faulty custom markers #55

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10 changes: 5 additions & 5 deletions package-lock.json
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160 changes: 123 additions & 37 deletions packages/tools/src/browser/repl-connection.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -12,14 +12,33 @@ export interface ReplConnectionOptions {
}

interface PendingEvaluation {
kind: "evaluation";
startMarker: string;
endMarker: string;
resultReady: boolean;
result?: unknown;
timeout: NodeJS.Timeout;
resolve: (result: unknown) => void;
reject: (error: Error) => void;
parse: (payload: string, outputBeforePayload: string) => unknown;
}

type ReplPrompt = "primary" | "continuation";

interface ReplPromptResult {
output: string;
prompt: ReplPrompt;
}

interface PendingPrompt {
kind: "prompt";
timeout: NodeJS.Timeout;
resolve: (result: ReplPromptResult) => void;
reject: (error: Error) => void;
}

type PendingRequest = PendingEvaluation | PendingPrompt;

const DEFAULT_HOST = "127.0.0.1";
const DEFAULT_CONNECT_TIMEOUT_MS = 5_000;
const DEFAULT_EVALUATE_TIMEOUT_MS = 30_000;
Expand Down Expand Up @@ -140,7 +159,7 @@ export class ReplConnection {
private _socket: net.Socket | null = null;
private _connectPromise: Promise<void> | null = null;
private _buffer = "";
private _pending: PendingEvaluation | null = null;
private _pending: PendingRequest | null = null;
private _sendQueue: Promise<void> = Promise.resolve();

constructor(options: ReplConnectionOptions) {
Expand Down Expand Up @@ -275,8 +294,10 @@ export class ReplConnection {
}, this._evaluateTimeoutMs);

this._pending = {
kind: "evaluation",
startMarker,
endMarker,
resultReady: false,
timeout,
resolve: result => resolve(result as EvaluateResult),
reject,
Expand All @@ -301,30 +322,41 @@ export class ReplConnection {
return this._sendRawCommand(socket, code, code);
}

private _sendRawCommand(socket: net.Socket, code: string, timeoutDescription: string): Promise<string> {
const id = randomUUID();
const startMarker = `__TESTPLANE_MCP_RAW_RESULT_${id}__`;
const endMarker = `__TESTPLANE_MCP_RAW_END_${id}__`;
const markerCommand = this._createRawCompletionMarkerCommand(startMarker, endMarker);
const command = `${code.endsWith("\n") ? code : `${code}\n`}${markerCommand}`;
private async _sendRawCommand(socket: net.Socket, code: string, timeoutDescription: string): Promise<string> {
const lines = splitReplLines(code);
const output: string[] = [];

return new Promise((resolve, reject) => {
// The REPL may process a later input line while a top-level await is still pending.
// Submit each physical line only after the preceding prompt has arrived.
for (let index = 0; index < lines.length; index++) {
const result = await this._sendRawLine(socket, lines[index], timeoutDescription);
output.push(result.output);

if (index === lines.length - 1 && result.prompt === "continuation") {
await this._sendRawLine(socket, ".break", "clearing incomplete REPL input");
throw new Error(`Testplane REPL requested more input after the end of: ${timeoutDescription}`);
}
}

return normalizeReplOutput(output.join(""));
}

private _sendRawLine(socket: net.Socket, line: string, timeoutDescription: string): Promise<ReplPromptResult> {
return new Promise<ReplPromptResult>((resolve, reject) => {
const timeout = setTimeout(() => {
this._pending = null;
reject(new Error(`Timed out waiting for Testplane REPL command to finish for: ${timeoutDescription}`));
reject(new Error(`Timed out waiting for Testplane REPL prompt while running: ${timeoutDescription}`));
}, this._evaluateTimeoutMs);

this._buffer = "";
this._pending = {
startMarker,
endMarker,
kind: "prompt",
Comment on lines 351 to +353

@chatgpt-codex-connector chatgpt-codex-connector Bot Jul 22, 2026

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P2 Badge Ignore the startup prompt before completing raw lines

When sendRaw() is the first operation on a fresh ReplConnection, the REPL's initial > prompt can arrive after this prompt waiter is installed but before the line has been evaluated. That startup prompt then resolves the fallback command immediately, so the next raw line can be completed by the fallback's later undefined\n> output and return the wrong result while the user's actual output remains on the socket; drain or explicitly ignore the connection's initial prompt before using prompt-only completion.

Useful? React with 👍 / 👎.

timeout,
resolve: result => resolve(result as string),
resolve,
reject,
parse: (_payload, outputBeforePayload) => stripReplPrompts(outputBeforePayload),
};

socket.write(command);
socket.write(`${line}\n`);
this._tryResolvePending();
});
}
Expand All @@ -337,10 +369,6 @@ export class ReplConnection {
return `void eval(${serializeFunctionExpression(installBrowserFallback)}).call(this)\n`;
}

private _createRawCompletionMarkerCommand(startMarker: string, endMarker: string): string {
return `({ [Symbol.for("nodejs.util.inspect.custom")]: () => ${JSON.stringify(startMarker + endMarker)} })\n`;
}

private _onData(data: string): void {
this._buffer = stripVTControlCharacters(this._buffer + data);
this._tryResolvePending();
Expand All @@ -352,28 +380,56 @@ export class ReplConnection {
return;
}

const startIndex = this._buffer.indexOf(pending.startMarker);
if (startIndex === -1) {
if (pending.kind === "prompt") {
const result = findTrailingReplPrompt(this._buffer);
if (!result) {
return;
}

const output = this._buffer.slice(0, result.index);
this._buffer = this._buffer.slice(result.index + result.length);
this._pending = null;
clearTimeout(pending.timeout);
pending.resolve({ output, prompt: result.prompt });
return;
}

const payloadStart = startIndex + pending.startMarker.length;
const endIndex = this._buffer.indexOf(pending.endMarker, payloadStart);
if (endIndex === -1) {
if (!pending.resultReady) {
const startIndex = this._buffer.indexOf(pending.startMarker);
if (startIndex === -1) {
return;
}

const payloadStart = startIndex + pending.startMarker.length;
const endIndex = this._buffer.indexOf(pending.endMarker, payloadStart);
if (endIndex === -1) {
return;
}

const outputBeforePayload = this._buffer.slice(0, startIndex);
const payload = this._buffer.slice(payloadStart, endIndex).trim();
this._buffer = this._buffer.slice(endIndex + pending.endMarker.length);

try {
pending.result = pending.parse(payload, outputBeforePayload);
pending.resultReady = true;
} catch (error) {
this._pending = null;
clearTimeout(pending.timeout);
pending.reject(error instanceof Error ? error : new Error(String(error)));
return;
}
}

const prompt = findTrailingReplPrompt(this._buffer);
if (!prompt || prompt.prompt !== "primary") {
return;
}

const outputBeforePayload = this._buffer.slice(0, startIndex);
const payload = this._buffer.slice(payloadStart, endIndex).trim();
this._buffer = this._buffer.slice(endIndex + pending.endMarker.length);
this._buffer = this._buffer.slice(prompt.index + prompt.length);
this._pending = null;
clearTimeout(pending.timeout);

try {
pending.resolve(pending.parse(payload, outputBeforePayload));
} catch (error) {
pending.reject(error instanceof Error ? error : new Error(String(error)));
}
pending.resolve(pending.result);
}

private _rejectPending(error: Error): void {
Expand All @@ -388,11 +444,41 @@ export class ReplConnection {
}
}

function stripReplPrompts(output: string): string {
const lines = stripVTControlCharacters(output)
.replace(/\r\n/g, "\n")
.split("\n")
.map(line => line.replace(/^(?:> |\.\.\. )+/, ""));
function splitReplLines(source: string): string[] {
const normalized = source.replace(/\r\n/g, "\n").replace(/\r/g, "\n");
const lines = normalized.split("\n");

if (lines.length > 1 && lines[lines.length - 1] === "") {
lines.pop();
}

return lines;
}

function findTrailingReplPrompt(buffer: string): { index: number; length: number; prompt: ReplPrompt } | undefined {
const prompts: Array<{ value: string; prompt: ReplPrompt }> = [
{ value: "... ", prompt: "continuation" },
{ value: "> ", prompt: "primary" },
];

for (const candidate of prompts) {
if (!buffer.endsWith(candidate.value)) {
continue;
}

// Prompts share a stream with user output, so only accept a prompt-shaped suffix
// at a line boundary. This is intentionally best-effort rather than collision-proof.
const index = buffer.length - candidate.value.length;
if (index === 0 || buffer[index - 1] === "\n") {
return { index, length: candidate.value.length, prompt: candidate.prompt };
}
}

return undefined;
}

function normalizeReplOutput(output: string): string {
const lines = stripVTControlCharacters(output).replace(/\r\n/g, "\n").split("\n");

while (lines.length > 0 && lines[0].trim() === "") {
lines.shift();
Expand Down
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