feat: warn against high price impact at confirm step

[gomesalexandre]

Description

Now that we have custom slippage under flag, we can implement #4858, since users may input custom slippage up to 30%, effectively having a maximum downside of 30% on the trade itself (excluding fees, which are separate from the trade value and are typically paid in addition to it for most swappers).

Disregard this. This is only implemented for price impact (the fiat difference between what you're selling and what you're getting), discusses this one out with @reallybeard and confirmed having slippage under the same umbrella would be all sorts of weird.

Pull Request Type

• 🐛 Bug fix (Non-breaking Change: Fixes an issue)
• 🛠️ Chore (Non-breaking Change: Doc updates, pkg upgrades, typos, etc..)
• 💅 New Feature (Breaking/Non-breaking Change)

Issue (if applicable)

closes #4858

Risk

This may show when it shouldn't, test accordingly

Testing

• Try an unfavorable trade e.g UTXO to ETH with THOR and the smallest amount you can swap (e.g 100 DOGE to ETH, might be more like 200 at the time you're testing this)
• Note, we don't properly handle minimums and balance checks after the multi-hop refactor (Swapper balance check is broken  #5011) so you'll see weird negative values until we get that fixed, if you're under the minimum or the quote fails for any reason related to your balance
• Ensure the price impact is reflected with a confirm window
• Disregard me ~~With the custom slippage flag on, add custom slippage e.g 9% (which is lower than the 10% minimum heuristics to display the confirm window), and ensure that the unfavorable downside (~60% at the time of testing) takes precedence over the custom slippage~~
• Disregard me Repeat the above with a favorable trade (e.g ERC-20 -> ERC-20 on Gnosis) and high custom slippage, ensuring the high custom slippage is reflected with a confirmed window, not the price impact downside (which should be very low, closeish to 0)

Engineering

Operations

Screenshots (if applicable)

• High price impact

• Disregard me High slippage taking precedence over low price impact

• Disregard me High price impact taking precedence over low slippage

• Disregard meHigh slippage

[gomesalexandre]

Current dependencies on/for this PR:

• develop
  • PR feat: warn against high price impact at confirm step #5032 👈
    • PR feat: handle moderate price impact at input/confirm step #5033

This comment was auto-generated by Graphite.

[0xApotheosis]

Tested and working as described, though my only concerns are more from a product perspective.

The price impact percentage constant calculated in this PR includes the buy asset protocol fee in the receive amount, which is unrelated to price impacts caused by illiquid pools.

@shapeshift/product thoughts?

[0xApotheosis]

See testing notes at the bottom of the stack (#5033).