Bug #21677: Integer("08") raises an ArgumentError

• Status: Rejected
• Assignee: -
• Target version: -
• ruby -v: 3.3.0 - 3.3.8
• Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN

[ben (Björn Engelmann)]

ruby version: tried it with 3.3.0 and 3.3.8

When running the following ruby script:

p Integer("04")
p Integer("05")
p Integer("06")
p Integer("07")
p Integer("08")

I get the following output:

4
5
6
7
internal:kernel:307:in Integer': invalid value for Integer(): "08" (ArgumentError) from bug.rb:7:in '

it seems that "08" and "09" are for some reason not parsable, while all other number "00", "01", "02", "03", "04", "05", "06", and "07" are.

I would have expected the Integer-parser to have consistent behaviour, independent of the numbers that are parsed...

By the way: it the same for "008", "0008" and so on.

[ufuk (Ufuk Kayserilioglu)]

From the docs https://docs.ruby-lang.org/en/3.4/Kernel.html#method-i-Integer:

With base zero, string object may contain leading characters to specify the actual base (radix indicator):

Integer('0100')  # => 64  # Leading '0' specifies base 8.

So, your strings are interpreted as octal numbers (base-8) due to the leading zero, in which the value 08 is invalid.

If you want to do parsing in decimal (base-10), then you need to explicitly pass the base argument as 10.

[nagachika (Tomoyuki Chikanaga)]

• Status changed from Open to Rejected

Thanks for the report, and for checking this.
As Ufuk already stated, this is the intended behavior, and it is also clearly documented.

[retro (Josef Šimánek)]

Just adding to Ufuk's great explanation and to make it super clear, to fix your case, you need to call Integer('08', 10) and Integer('09', 10).