readline: initialize input before history manager

lib/internal/readline/interface.js

@@ -172,9 +172,11 @@ function InterfaceConstructor(input, output, completer, terminal) {
   let crlfDelay;
   let prompt = '> ';
   let signal;
+  let inputOptions;
 
   if (input?.input) {
     // An options object was given
+    inputOptions = input;
     output = input.output;
     completer = input.completer;
     terminal = input.terminal;
@@ -215,7 +217,6 @@ function InterfaceConstructor(input, output, completer, terminal) {
     input.removeHistoryDuplicates = removeHistoryDuplicates;
   }
 
-  this.setupHistoryManager(input);
 
   if (completer !== undefined && typeof completer !== 'function') {
     throw new ERR_INVALID_ARG_VALUE('completer', completer);
@@ -234,6 +235,24 @@ function InterfaceConstructor(input, output, completer, terminal) {
   this[kSubstringSearch] = null;
   this.output = output;
   this.input = input;
+
+  // If inputOptions was provided (constructor with options object),
+  // copy the stream's size/history properties back to it for setupHistoryManager
+  let historyOptions = inputOptions || input;
+  if (inputOptions !== undefined && input !== undefined &&
+      inputOptions !== input) {
+    if (input.size !== undefined && historyOptions.size === undefined) {
+      historyOptions.size = input.size;
+    }
+    if (input.history !== undefined && historyOptions.history === undefined) {
+      historyOptions.history = input.history;
+    }
+    if (input.removeHistoryDuplicates !== undefined &&
+        historyOptions.removeHistoryDuplicates === undefined) {
+      historyOptions.removeHistoryDuplicates = input.removeHistoryDuplicates;
+    }
+  }
+  this.setupHistoryManager(historyOptions);
   this[kUndoStack] = [];
   this[kRedoStack] = [];
   this[kPreviousCursorCols] = -1;
@@ -384,8 +403,19 @@ class Interface extends InterfaceConstructor {
   setupHistoryManager(options) {
     this.historyManager = new ReplHistory(this, options);
 
-    if (options.onHistoryFileLoaded) {
-      this.historyManager.initialize(options.onHistoryFileLoaded);
+    // Only initialize REPL history when called from REPL.setupHistory(),
+    // not from the readline constructor.
+    // Constructor passes: stream OR { input: stream, output: stream, ... }
+    // setupHistory passes: { filePath: ..., size: ..., onHistoryFileLoaded: ... }
+    // Detect constructor calls by checking for stream.on() or options.input
+    if (options && typeof options === 'object') {
+      const isStream = typeof options.on === 'function';
+      const hasInputProperty = options.input !== undefined;
+      const isFromConstructor = isStream || hasInputProperty;
+
+      if (!isFromConstructor && typeof options.onHistoryFileLoaded === 'function') {
+        this.historyManager.initialize(options.onHistoryFileLoaded);
+      }
     }
 
     ObjectDefineProperty(this, 'history', {

test/parallel/test-readline-history-init-order.js

@@ -0,0 +1,47 @@
+'use strict';
+
+const readline = require('readline');
+const { PassThrough } = require('stream');
+
+// Regression test for https://github.com/nodejs/node/issues/61526
+// This test ensures that createInterface() doesn't crash when input
+// has an onHistoryFileLoaded property (e.g., from a Proxy or jest.mock)
+
+// Test case 1: options object with onHistoryFileLoaded as function
+{
+  const input = new PassThrough();
+  input.onHistoryFileLoaded = () => {};
+
+  readline.createInterface({
+    input,
+    output: new PassThrough()
+  });
+}
+
+// Test case 2: options object without onHistoryFileLoaded
+{
+  const input = new PassThrough();
+  readline.createInterface({
+    input,
+    output: new PassThrough()
+  });
+}
+
+// Test case 3: options object with onHistoryFileLoaded as non-function
+{
+  const input = new PassThrough();
+  input.onHistoryFileLoaded = { some: 'object' };
+
+  readline.createInterface({
+    input,
+    output: new PassThrough()
+  });
+}
+
+// Test case 4: direct stream with onHistoryFileLoaded (original bug scenario)
+{
+  const input = new PassThrough();
+  input.onHistoryFileLoaded = () => {};
+
+  readline.createInterface(input, new PassThrough());
+}

test/parallel/test-repl-persistent-history.js

@@ -183,8 +183,10 @@ function cleanupTmpFile() {
 }
 
 // Copy our fixture to the tmp directory
+const writeStream = fs.createWriteStream(historyPath);
 fs.createReadStream(historyFixturePath)
-  .pipe(fs.createWriteStream(historyPath)).on('unpipe', () => runTest());
+  .pipe(writeStream);
+writeStream.on('finish', () => runTest());
 
 const runTestWrap = common.mustCall(runTest, numtests);