Not totally equivalent
Witch hexes are similar to warlock invocations: permanent or infinitely-usable magics. You even get a similar number of them. And like warlocks, witches pair their unlimited magic with more traditional, limited, spells. Finally, of course, witches and warlocks have similar fluff, being associated with patrons and having somewhat “darker” powers.
But the similarities end there. Witches use Intelligence while warlocks use Charisma. Witch spellcasting is basically the same as a wizard’s, just with the familiar storing spells instead of a book, and of course a somewhat different spell list. That means preparing spells—more onerous in Pathfinder than 5e—and recovering them on a “long rest,” which is the only rest Pathfinder has. It means you have more spell slots to worry about, and they come at different levels.
Also, the various Pacts—Blade, Chain, Tome—don’t really have analogues for the witch. You could take feats or other options to play up martial skills, your familiar, or spellcasting options, but the basic witch doesn’t provide you with an option like that. Considering her superior—albeit more complicated—spellcasting, it might help to think of all PF witches as being “Pact of the Tome,” sorta.
But probably the best match Pathfinder has
As mentioned, Pathfinder doesn’t have short rests, or much in the way of equivalent mechanics that one could leverage to produce anything similar to 5e Pact Magic. Further, Paizo was extremely—unreasonably, in my opinion—leery of “at-will” magic, so witch hexes are pretty unique; there aren’t really other classes with similar mechanics that you could use. And of course the patron thing is close, ish.
So there just isn’t really any other class we could point you to that would work better. I mean, shamans also have hexes—since they’re a “hybrid class” of oracle and witch—and for that matter, oracles might hit upon some similar thematic notes. A magus could maybe make a case for Pact of the Blade specifically. You could make arguments, probably, for a few other classes. But really witch is going to be the best you can get.
And we can make the witch a little closer.
Remember how I said that Pathfinder witches don’t have analogues for the various Pacts? That wasn’t quite true—the warlock Pacts, like bard College or druid Circle, are what are generically referred to as “subclasses” in 5e. That is, they are variant versions of some main class that you pick in the first couple of levels, and change your version of the class relative to someone who chose one of the other options.
Pathfinder has a much, much more complicated system for handling stuff like that: archetypes. Archetypes aren’t built into the class, the way 5e subclasses are, and you can easily play a class without any archetypes. Instead, archetypes are extra options that say stuff like “instead of getting X at nth level, you get Y,” where X and Y can basically be anything at all. There are tons and tons of these options for basically every class, and there are even rules for using more than one of them at a time.
In the case of the witch, the ley-line guardian witch gets spontaneous spellcasting, à la the sorcerer, which is marginally more similar to the warlock’s. It’s still Intelligence-based, however.
On the other hand, the seducer witch uses Charisma for everything, including spellcasting, which is more similar to the warlock. As the name implies, the seducer has some very particular thematics going on which may not be that appropriate for all characters, but ultimately that “just” affects your choice of patron, and everything else you can do can be independent.
The two aren’t compatible with one another—the rules I mentioned for using multiple archetypes wouldn’t allow them to both be used on the same witch, because the seducer gets particular (super-charged) hexes at 1st and 8th level, while the ley-line guardian gets a special “surge” ability instead of their hexes at 1st and 8th. But I think most GMs wouldn’t mind overly much if you wanted to combine them, and just replace seducer’s kiss and garden of delight with conduit surge (or replace conduit surge with seducer’s kiss and garden of delight). Doing that even reduces how “seductive” your character has to be, which is a plus for at least some warlocks.
There’s also a 3rd-party archetype, feytouched channeler, that gets both sorcerous spellcasting and being Charisma-based, all in one archetype. It’s not official, but I’d guess most GMs wouldn’t have any objection to it; it’s fairly simple and benign.
Finally, there was a previous question asking whether there was any “hex-only” version of the witch, ditching the spellcasting altogether. The answer there was no, as I exhaustively described in one answer, but I also wrote another answer, in which I wrote up my own hex-focused witch archetype. It wasn’t in at all inspired by the 5e warlock, but it might be worthy of consideration for your interests. As I said in that answer, I haven’t tested that archetype specifically (still, to my chagrin), but I have pretty good reasons to be confident in its balance.