Voca's title case function is capitalizing some words it shouldn't

[LandonSchropp]

Expected behavior 😸

When title casing an abbreviation, Voca capitalizes some words it shouldn't, like to or a. I realize this can get pretty complicated or can vary between styles, but it seems to me that it still be helpful to have a function that followed the general rules.

voca.titleCase("bruce willis is a badass") // => "Bruce Willis is a Badass"

Actual behavior 😿

Voca capitalizes those words.

voca.titleCase("bruce willis is a badass") // => 'Bruce Willis Is A Badass'

Steps to reproduce 👷

Call the functions as described above.

Technical details: 🔧

Browser/OS type: macOS 10.15.3
Node version: 13

[panzerdp]

Voca library isn't created specifically for English language, thus I cannot incorporate is or a into the function as a special case.

In the longterm, I plan to make some improvements to incorporate behavior by locale.

[JNavas2]

Voca library isn't created specifically for English language, thus I cannot incorporate is or a into the function as a special case.
In the long term, I plan to make some improvements to incorporate behavior by locale.

OK, but until then, it's not really Title Case. It's Capitalized Words, which you should make clear.
Another example (per AP style rules): "weight of up to 12 kg" should be "Weight of up to 12 kg" (not "Weight Of Up To 12 Kg").

Notes:

1. English is not a locale, it's a language. en-US and en-UK are locales.
2. Helpful resource: https://titlecaseconverter.com/

[panzerdp]

@JNavas2

OK, but until then, it's not really Title Case. It's Capitalized Words, which you should make clear.
Another example (per AP style rules): "weight of up to 12 kg" should be "Weight of up to 12 kg" (not "Weight Of Up To 12 Kg").

This is an open source project. Create a PR with the fix and I will take a look.

English is not a locale, it's a language. en-US and en-UK are locales.

Thank you for teaching me, I appreciate it!

[JNavas2]

@panzerdp
Thank you for being so receptive.
Good title case rules are not simple, and there is more than one style.
AP (Associated Press) title case style rules summarized:

• Capitalize the first word and the last word of the title
• Capitalize the principal words
• Capitalize "to" in infinitives
• Capitalize all words of four letters or more
• Do not capitalize articles, conjunctions, and prepositions of three letters or fewer

Simplified rule that you might want to consider: Capitalize any word that is three letters or more, except for articles, short prepositions, and short conjunctions. I would also suggest not changing case of words in all caps, so that (for example) NATO does not become Nato.