readline: fix detection of carriage return

aduh95 · ruyadorno · commit 4ae2492a33ce · 2023-01-31T18:16:08.000-05:00
Fixes: #45992 PR-URL: #46306 Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de> Reviewed-By: Luigi Pinca <luigipinca@gmail.com> Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
diff --git a/lib/internal/readline/interface.js b/lib/internal/readline/interface.js
@@ -598,6 +598,7 @@ class Interface extends InterfaceConstructor {
       if (this[kLine_buffer]) {
         string = this[kLine_buffer] + string;
         this[kLine_buffer] = null;
+        lineEnding.lastIndex = 0; // Start the search from the beginning of the string.
         newPartContainsEnding = RegExpPrototypeExec(lineEnding, string);
       }
       this[kSawReturnAt] = StringPrototypeEndsWith(string, '\r') ?
diff --git a/test/known_issues/test-readline-big-file-carriage-return.js b/test/known_issues/test-readline-big-file-carriage-return.js
diff --git a/test/parallel/test-readline-carriage-return-between-chunks.js b/test/parallel/test-readline-carriage-return-between-chunks.js
@@ -0,0 +1,23 @@
+'use strict';
+
+const common = require('../common');
+
+const assert = require('node:assert');
+const readline = require('node:readline');
+const { Readable } = require('node:stream');
+
+
+const input = Readable.from((function*() {
+  yield 'a\nb';
+  yield '\r\n';
+})());
+const rl = readline.createInterface({ input, crlfDelay: Infinity });
+let carriageReturns = 0;
+
+rl.on('line', (line) => {
+  if (line.includes('\r')) carriageReturns++;
+});
+
+rl.on('close', common.mustCall(() => {
+  assert.strictEqual(carriageReturns, 0);
+}));

Original file line number	Diff line number	Diff line change
`@@ -598,6 +598,7 @@ class Interface extends InterfaceConstructor {`
`598`	`598`	`if (this[kLine_buffer]) {`
`599`	`599`	`string = this[kLine_buffer] + string;`
`600`	`600`	`this[kLine_buffer] = null;`
	`601`	`+ lineEnding.lastIndex = 0; // Start the search from the beginning of the string.`
`601`	`602`	`newPartContainsEnding = RegExpPrototypeExec(lineEnding, string);`
`602`	`603`	`}`
`603`	`604`	`this[kSawReturnAt] = StringPrototypeEndsWith(string, '\r') ?`