From 9decb70d05c90a99beed402a4867691f313e2fd9 Mon Sep 17 00:00:00 2001 From: Ian Harris Date: Fri, 14 Apr 2023 03:12:16 -0700 Subject: [PATCH] readline: fix issue with newline-less last line The logic for reading lines was slightly flawed, in that it assumed there would be a final new line. It handled the case where there are no new lines, but this then broke if there were some new lines. The fix in logic is basically removing the special case where there are no new lines by changing it to always read the final line with no new lines. This works because if a file contains no new lines, the final line is the first line, and all is well. There is some subtlety in this functioning, however. If the last line contains no new lines, then `lastIndex` will be the start of the last line, and `kInsertString` will be called from that point. If it does contain a new line, `lastIndex` will be equal to `s.length`, so the slice will be the empty string. Fixes: https://github.com/nodejs/node/issues/47305 PR-URL: https://github.com/nodejs/node/pull/47317 Reviewed-By: Antoine du Hamel --- lib/internal/readline/interface.js | 26 ++++++------ ...repl-load-multiline-no-trailing-newline.js | 7 ++++ ...-readline-interface-no-trailing-newline.js | 24 +++++++++++ ...repl-load-multiline-no-trailing-newline.js | 42 +++++++++++++++++++ 4 files changed, 85 insertions(+), 14 deletions(-) create mode 100644 test/fixtures/repl-load-multiline-no-trailing-newline.js create mode 100644 test/parallel/test-readline-interface-no-trailing-newline.js create mode 100644 test/parallel/test-repl-load-multiline-no-trailing-newline.js diff --git a/lib/internal/readline/interface.js b/lib/internal/readline/interface.js index 4a5ec497369..df08875cc79 100644 --- a/lib/internal/readline/interface.js +++ b/lib/internal/readline/interface.js @@ -1324,21 +1324,19 @@ class Interface extends InterfaceConstructor { if (typeof s === 'string' && s) { // Erase state of previous searches. lineEnding.lastIndex = 0; - let nextMatch = RegExpPrototypeExec(lineEnding, s); - // If no line endings are found, just insert the string as is. - if (nextMatch === null) { - this[kInsertString](s); - } else { - // Keep track of the end of the last match. - let lastIndex = 0; - do { - this[kInsertString](StringPrototypeSlice(s, lastIndex, nextMatch.index)); - ({ lastIndex } = lineEnding); - this[kLine](); - // Restore lastIndex as the call to kLine could have mutated it. - lineEnding.lastIndex = lastIndex; - } while ((nextMatch = RegExpPrototypeExec(lineEnding, s)) !== null); + let nextMatch; + // Keep track of the end of the last match. + let lastIndex = 0; + while ((nextMatch = RegExpPrototypeExec(lineEnding, s)) !== null) { + this[kInsertString](StringPrototypeSlice(s, lastIndex, nextMatch.index)); + ({ lastIndex } = lineEnding); + this[kLine](); + // Restore lastIndex as the call to kLine could have mutated it. + lineEnding.lastIndex = lastIndex; } + // This ensures that the last line is written if it doesn't end in a newline. + // Note that the last line may be the first line, in which case this still works. + this[kInsertString](StringPrototypeSlice(s, lastIndex)); } } } diff --git a/test/fixtures/repl-load-multiline-no-trailing-newline.js b/test/fixtures/repl-load-multiline-no-trailing-newline.js new file mode 100644 index 00000000000..605d49e2d05 --- /dev/null +++ b/test/fixtures/repl-load-multiline-no-trailing-newline.js @@ -0,0 +1,7 @@ +// The lack of a newline at the end of this file is intentional. +const getLunch = () => + placeOrder('tacos') + .then(eat); + +const placeOrder = (order) => Promise.resolve(order); +const eat = (food) => ''; \ No newline at end of file diff --git a/test/parallel/test-readline-interface-no-trailing-newline.js b/test/parallel/test-readline-interface-no-trailing-newline.js new file mode 100644 index 00000000000..b3392db8619 --- /dev/null +++ b/test/parallel/test-readline-interface-no-trailing-newline.js @@ -0,0 +1,24 @@ +'use strict'; +const common = require('../common'); +const ArrayStream = require('../common/arraystream'); +const assert = require('assert'); + +common.skipIfDumbTerminal(); + +const readline = require('readline'); +const rli = new readline.Interface({ + terminal: true, + input: new ArrayStream(), + output: new ArrayStream(), +}); + +// Minimal reproduction for #47305 +const testInput = '{\n}'; + +let accum = ''; + +rli.output.write = (data) => accum += data.replace('\r', ''); + +rli.write(testInput); + +assert.strictEqual(accum, testInput); diff --git a/test/parallel/test-repl-load-multiline-no-trailing-newline.js b/test/parallel/test-repl-load-multiline-no-trailing-newline.js new file mode 100644 index 00000000000..f57638d2521 --- /dev/null +++ b/test/parallel/test-repl-load-multiline-no-trailing-newline.js @@ -0,0 +1,42 @@ +'use strict'; +const common = require('../common'); +const ArrayStream = require('../common/arraystream'); +const fixtures = require('../common/fixtures'); +const assert = require('assert'); +const repl = require('repl'); + +common.skipIfDumbTerminal(); + +const command = `.load ${fixtures.path('repl-load-multiline-no-trailing-newline.js')}`; +const terminalCode = '\u001b[1G\u001b[0J \u001b[1G'; +const terminalCodeRegex = new RegExp(terminalCode.replace(/\[/g, '\\['), 'g'); + +const expected = `${command} +// The lack of a newline at the end of this file is intentional. +const getLunch = () => + placeOrder('tacos') + .then(eat); + +const placeOrder = (order) => Promise.resolve(order); +const eat = (food) => ''; +undefined +`; + +let accum = ''; + +const inputStream = new ArrayStream(); +const outputStream = new ArrayStream(); + +outputStream.write = (data) => accum += data.replace('\r', ''); + +const r = repl.start({ + prompt: '', + input: inputStream, + output: outputStream, + terminal: true, + useColors: false +}); + +r.write(`${command}\n`); +assert.strictEqual(accum.replace(terminalCodeRegex, ''), expected); +r.close();