Add preserveConsecutiveUppercase option to CamelCase and add SplitWords type

[skarab42]

Fix #224
Fix #488

expectType<CamelCase<'fooBAR'>>('fooBAR');
expectType<CamelCase<'fooBAR', {preserveConsecutiveUppercase: false}>>('fooBar');

expectType<CamelCase<'fooBARBiz'>>('fooBARBiz');
expectType<CamelCase<'fooBARBiz', {preserveConsecutiveUppercase: false}>>('fooBarBiz');

expectType<CamelCase<'foo BAR-Biz_BUZZ'>>('fooBARBizBUZZ');
expectType<CamelCase<'foo BAR-Biz_BUZZ', {preserveConsecutiveUppercase: false}>>('fooBarBizBuzz');

In anticipation for #336 this PR also adds the SplitWords type (internal for now).

type Words0 = SplitWords<'helloWorld'>; // ['hello', 'World']
type Words1 = SplitWords<'helloWORLD'>; // ['hello', 'WORLD']
type Words2 = SplitWords<'hello-world'>; // ['hello', 'world']
type Words3 = SplitWords<'--hello the_world'>; // ['hello', 'the', 'world']
type Words4 = SplitWords<'lifeIs42'>; // ['life', 'Is', '42']

[sindresorhus]

Nice work 👍

[RichiCoder1]

It seems like this PR and camelcase have two different behaviors:

• camelCase("TPSCode", { preserveConsecutiveUppercase: true}) => TPSCode
• CamelCase<'TPSCode', {preserveConsecutiveUppercase: true}> => tPSCode

Is there anyway to fix or consolidate this behavior?

[skarab42]

Is there anyway to fix or consolidate this behavior?

@RichiCoder1 As a temporary fix you can use Capitalize

[ulken]

Since PascalCase uses CamelCase under the hood, I'd expect the options to propagate. Upgrading broke existing usages of PascalCase, without (seemingly) any way to get the old behavior back.

I can work around it, but I still think it should be configurable.