ASCII File Detected as ISO-8859-1 Due to Control Characters

[mpytel-cksource]

Description

When detecting the character set of a plain ASCII file containing newline (\n, ASCII 10) or other control characters, chardet incorrectly identifies it as ISO-8859-1 instead of ASCII. This happens because control characters (ASCII 0-31, 127) are present, which seems to influence the detection process.

Since ASCII includes both printable characters (32-126) and control characters (0-31, 127), the presence of these should not change the classification to a different encoding like ISO-8859-1.

Expected Behavior

Files containing only bytes 0-127 (including control characters like \n) should be correctly detected as ASCII, not ISO-8859-1.

Steps to Reproduce

1. Create a file (ascii.txt) with the following content:

Hello, World!
This is a test.

(Ensure there is a newline at the end of the file.)

2. Run the following script:

import chardet from 'chardet';

console.log(chardet.detectFileSync('ascii.txt')); // Expected: 'ASCII', but gets 'ISO-8859-1']