[SR-12375] Refactoring: Extract Method to Extension

[swift-ci]

Previous ID	SR-12375
Radar	rdar://problem/60832823
Original Reporter	mariusLAN (JIRA User)
Type	Bug

Additional Detail from JIRA

| | | |------------------|-----------------| |Votes | 0 | |Component/s | Source Tooling | |Labels | Bug, Refactoring | |Assignee | None | |Priority | Medium | md5: a2f9fdaa45b849292dacbd0493741cee

Issue Description:

When writig complex Code FP-Style you may want to give the other Developers a better naming style to see what exactly is going on there without heading in every implementation.

The Input may have an complex reduce, map, compactMap, flatMap, sort, etc.

let foo = [
    "bar": ["baz", "buz"],
    "faz": ["baz", "buz"]
]

foo
    .sorted{ $0.key > $1.key }
    .reduce("") { (result, keyValue) -> String in
        keyValue.key + keyValue.value.joined()
    }

The goal would be to extract the reduce Method to a extension on sorted and name it properly:

let foo = [
    "bar": ["baz", "buz"],
    "faz": ["baz", "buz"]
]

foo
    .sorted{ $0.key > $1.key }
    .glueAllTogether()

extension Sequence where Element == (key: String, value: [String]) {
    func glueAllTogether() -> String {
        reduce("") { (result, keyValue) -> String in
            keyValue.key + keyValue.value.joined()
        }
    }
}

The Code is extracted properly, easy to test and better to read for all devs.

[beccadax]

@swift-ci create