As a character class, the witch has had a hard time getting off the metaphorical ground in Dungeons & Dragons. In fact, it’s notable that the most famous instances of a witch class come from various third parties, such as Mayfair Games and Paizo Publishing.
But, in a bit of sleight of hand that a lot of people overlooked (helped by it never getting included in the SRD), D&D slipped a witch class into its Third Edition, right there on pages 26-27 of the 3.0 Dungeon Master’s Guide and page 175 of the 3.5 DMG (the latter of which is depicted below).

Okay, so that’s just a spell list rather than a full class presentation. Indeed, this is the example that’s presented as what a customized spell list could look like; the section on developing entirely new classes (though it largely discusses this in terms of variations of an existing class) is actually the one right after that. Still, the text accompanying the witch spell list says that a witch “[…] casts spells as a sorcerer, using the sorcerer’s Spells per Day table […] and her spells are based on Charisma.” From there, it’s not hard to make the leap that in 3.5, a witch character uses the sorcerer class in all ways, save for using the above spell list instead of the standard sorcerer/wizard one in the Player’s Handbook.
It might have been a bit of a bait-and-switch, but the witch found her niche.
The 3.0 Witch Spell List
One thing that’s interesting to consider is how the witch spell list in 3.0 differed from its 3.5 counterpart. For the most part they’re identical (or at least, they are after you apply the errata). However, there are a few differences between them, which you can reintroduce if you want a witch character to feel slightly more different from her spellcasting counterparts.
Make speak with animals a 2nd-level spell.
Make baleful polymorph a 4th-level spell.
Add animal growth to the witch’s 5th-level spells.
Make greater scrying a 5th-level spell.
Finally, consider deleting the spells crushing despair (4th), good hope (4th), and rage (3rd), instead replacing them with emotion as a 4th-level spell. Emotion was removed from the 3.5 version of the game (with several of its effects becoming their own spells), but bringing it back just for the witch can be a good way to make the class a little more unique.
For pricing the witch spell list as a magic progression in Eclipse: The Codex Persona (page 11), I’d recommend making it equal in cost to the bard, cleric (no package), and druid progressions.