Bug #20566: string << 0xC2 should raise a RangeError if the string encoding is Encoding::ASCII

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 3.4.0preview1 (2024-05-16 master 9d69619623) [x86_64-linux]
• Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN

[postmodern (Hal Brodigan)]

I noticed that appending extended ASCII characters (0x80 - 0xff) works when the String's encoding is Encoding::ASCII, as well as Encoding::ASCII_8BIT. I was under the impression that Encoding::ASCII only covers the regular ASCII character set (0x00 - 0x7F). I believe appending 0xC2 to a String with Encoding::ASCII should raise a RangeError.

Steps To Reproduce

str = String.new(encoding: Encoding::ASCII)
str << 0xC2

Expected Result

RangeError: character 194 is out of range

Actual Result

"\xC2"

[nobu (Nobuyoshi Nakada)]

• Related to Bug #18973: Kernel#sprintf: %c allows codepoints above 127 for 7-bits ASCII encoding added

[nobu (Nobuyoshi Nakada)]

It is a spec.

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed

Applied in changeset git|dd8903fed72c2d06fe7a0ca6b5ef88e9140be451.

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[Bug #20566] Mention out-of-range argument cases in String#<<

Also [Bug #18973].