CSV parser for Swift
Take a look at Swift libraries for CSV parsing and encoding like SwiftCSV which cover all of the possible exceptions and formats of a valid CSV file. They are not huge but not insignificant libraries either.
NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a more popular project.
Reading from spreadsheet
1 project | reddit.com/r/SwiftUI | 9 Mar 2021
Let user load a csv file and read it
2 projects | reddit.com/r/iOSProgramming | 25 Jun 2021
Visidata 2.9.1 Released– Excel/CSV/JSON/SQLite/Parquet in the Terminal (TUI/CLI)
1 project | news.ycombinator.com | 12 Aug 2022
CSV syntax highlighting?
2 projects | reddit.com/r/vim | 10 Aug 2022
Convert a Single line of JSON to csv using jq in shell bash script
2 projects | reddit.com/r/commandline | 24 Jul 2022