feat(NODE-5648): add Long.fromStringStrict()

[aditi-khare-mongoDB]

Description

Add Long.fromStringStrict which throws an error if the input string has invalid characters.

What is changing?

See above.

Is there new documentation needed for these changes?

Yes, we should request docs changes, and there is an API docs addition.

What is the motivation for this change?

User submitted bug: NODE-5638.

Release Highlight

Add Long.fromStringStrict method

The Long.fromStringStrict method is almost identical to the Long.fromString method, except it throws a BSONError if any of the following are true:

• input string has invalid characters, for the given radix
• the string contains whitespace
• the value the input parameters represent is too large or too small to be a 64-bit Long

Unlike Long.fromString, this method does not coerce the inputs '+/-Infinity' and 'NaN' to Long.ZERO, in any case.

Examples:

Long.fromStringStrict('1234xxx5'); // throws BSONError
Long.fromString('1234xxx5'); // coerces input and returns new Long(123400)

// when writing in radix 10, 'n' and 'a' are both invalid characters
Long.fromStringStrict('NaN'); // throws BSONError
Long.fromString('NaN'); // coerces input and returns Long.ZERO

Note

Long.fromStringStrict's functionality will be present in Long.fromString in the V7 BSON release.

Double check the following

• Ran npm run check:lint script
• Self-review completed using the steps outlined here
• PR title follows the correct format: type(NODE-xxxx)[!]: description
  • Example: feat(NODE-1234)!: rewriting everything in coffeescript
• Changes are covered by tests
• New TODOs have a related JIRA ticket

[baileympearson]

Why are we checking the radix here? This changes the behavior of Long.fromString - something we want to avoid in this PR. The logic was previously:

if (str === 'NaN' || str === 'Infinity' || str === '+Infinity' || str === '-Infinity')
      return Long.ZERO;

[aditi-khare-mongoDB]

It does change the behavior of Long.fromString, but its another bug fix, (see updated release notes).

We previously did not allow valid inputs to radices, because we interpreted them as 'not a number,' but in radix >= 24, 'nan' is a valid number (since 'n' and 'a' are in the character set for numbers).

Example:
Long.fromString('NaN', 27); // new Long(17060)

The original Long.fromString would return Long.ZERO on '+/- Infinity' and 'NaN' cases, and then check for radix later. This behavior is still preserved, other than in the case that the user is not actually inputting 'not a number' or an infinite value, but a valid non-infinite Long written in a high radix.