refactor(ecocredit/marketplace): BuyDirect

[technicallyty]

Description

• refactors Buy to only deal with filtered buy orders
• creates new BuyDirect rpc method for purchasing directly from sell orders.
• fixes an issue with calculating the total cost
• adds test case for fractional purchase

Closes: #905

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• confirmed the correct type prefix in the PR title
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[codecov]

Codecov Report

Merging #967 (b0a45d3) into master (404cc06) will decrease coverage by 0.07%.
The diff coverage is 57.54%.

❗ Current head b0a45d3 differs from pull request most recent head 1c05433. Consider uploading reports for the commit 1c05433 to get more accurate results

@@            Coverage Diff             @@
##           master     #967      +/-   ##
==========================================
- Coverage   72.25%   72.17%   -0.08%     
==========================================
  Files         212      212              
  Lines       23521    23681     +160     
==========================================
+ Hits        16994    17091      +97     
- Misses       5168     5216      +48     
- Partials     1359     1374      +15     

Flag	Coverage Δ
experimental-codecov	72.08% <57.54%> (-0.07%)	⬇️
stable-codecov	67.06% <57.54%> (-0.04%)	⬇️

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[robert-zaremba]

int64 roundtrip doesn't look good. Let's revisit.

[robert-zaremba]

int64 roundtrip doesn't look good. Let's revisit.

[ryanchristo]

Looking good. Should we use bid_price rather than changing the name? Do we want to support multiple orders in the same message as we do for Sell and Buy?

[ryanchristo]

I think we should support multiple buy orders. Otherwise looks good.

[ryanchristo]

We'll also need a followup task for updating the CLI command.

[technicallyty]

We'll also need a followup task for updating the CLI command.

#983

[aaronc]

Please delete the Buy method and also buy.go so the diff shows buy_direct.go renamed to buy.go. That will be easier to review

[robert-zaremba]

pre-approving. Left few suggestions.

[ryanchristo]

Pre-approving with a few minor suggestions.

[ryanchristo]

Might be nice to provide the whole error and use equals rather than contains but ok leave as is.

Addressed