From 92cd0b65d255428d823ee8f04b56984457a58d8d Mon Sep 17 00:00:00 2001
From: Mathias Wulff <m@rawu.dk>
Date: Fri, 23 Oct 2026 23:30:22 +1100
Subject: [PATCH] Use the path of --replacement-file as it is, with no escapes
 and no aliases

---
 src/alias.ts         |  5 ++++-
 src/cli.ts           |  3 ++-
 test/fix/817.test.js | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 38 insertions(+), 2 deletions(-)
 create mode 100644 test/fix/817.test.js

diff --git a/src/alias.ts b/src/alias.ts
index e872b519..8eace72c 100644
--- a/src/alias.ts
+++ b/src/alias.ts
@@ -15,7 +15,10 @@ export function alias(config) {
 	};
 
 	config.pattern = swap(config.pattern);
-	config.replacement = swap(config.replacement);
+	// With --replacement-file the replacement is the name of a file, unless --js code gives the name
+	if (!config.replacementFile || config.replacementJs) {
+		config.replacement = swap(config.replacement);
+	}
 	config.excludeRe = config.excludeRe.map(swap);
 	config.delimiter = swap(config.delimiter);
 	config.nameDelimiter = swap(config.nameDelimiter);
diff --git a/src/cli.ts b/src/cli.ts
index 8b1b73d2..5b568196 100644
--- a/src/cli.ts
+++ b/src/cli.ts
@@ -623,7 +623,8 @@ const unescape = (key, name) => {
 	}
 };
 
-if (!config.replacementJs) {
+// The path of --replacement-file is the name of a file, so it has no escapes
+if (!config.replacementJs && !config.replacementFile) {
 	unescape('replacement', 'replacement');
 }
 
diff --git a/test/fix/817.test.js b/test/fix/817.test.js
new file mode 100644
index 00000000..35d54fdc
--- /dev/null
+++ b/test/fix/817.test.js
@@ -0,0 +1,32 @@
+// https://github.com/mathiasrw/rexreplace/issues/817
+// The path of --replacement-file went through the escapes and the € and § aliases of a typed replacement,
+// so a backslash in a Windows path was lost, and price€.txt was looked for as price$.txt.
+import {describe, test, expect} from 'bun:test';
+import fs from 'fs';
+import {$} from 'bun';
+import {cli, sh} from '../helper.js';
+
+describe('#817 the path of --replacement-file', () => {
+	test('keeps a backslash', async () => {
+		fs.mkdirSync('my\\dir');
+		fs.writeFileSync('my\\dir/new.txt', 'NEW');
+		fs.writeFileSync('page.txt', 'X');
+		const result = await sh($`bun ${cli} X ${'my\\dir/new.txt'} page.txt -o --replacement-file`);
+		expect(result).toEqual({out: 'NEW\n', err: 'page.txt\n', exit: 0});
+	});
+
+	test('keeps € and §, as the aliases are not used in file names', async () => {
+		fs.writeFileSync('priceۤ.txt', 'PRICE');
+		fs.writeFileSync('page.txt', 'X');
+		const result = await sh($`bun ${cli} X ${'priceۤ.txt'} page.txt -o --replacement-file`);
+		expect(result.out).toBe('PRICE\n');
+	});
+
+	test('still uses the aliases in the code of --js, which gives the path', async () => {
+		fs.writeFileSync('new.txt', 'NEW');
+		fs.writeFileSync('page.txt', 'X');
+		const code = '"new" + €0.replace("X", ".txt")';
+		const result = await sh($`bun ${cli} X ${code} page.txt -o --replacement-file --js`);
+		expect(result.out).toBe('NEW\n');
+	});
+});