Add Collection conformances to ChartDataSet types

[jjatie]

Goals ⚽

Allow more familiar API for collection types, the ability to implement more generic algorithms and simplify many existing algorithms by taking advantage of Collection conformances.

Implementation Details 🚧

ChartDataSet adopts conformances:
MutableCollection
RandomAccessCollection
RangeReplaceableCollection

[liuxuan30]

should we use 4.0 branch? I suppose there would be conflicts later.

[liuxuan30]

I'm checking isIndirectValuesCall here, it seems in remove(at:), we didn't call isIndirectValuesCall = true and we delete it here. Is it a mistake?

[jjatie]

This was on purpose. We always want to call notifiyDataSetChanged in our current implementation, so I go rid of it and let the property observer take car of it.

[liuxuan30]

BTW, should we use 4.0 branch? I suppose there would be conflicts later? I'm going to try merge a few PRs and release a new version. Not sure if we should include this one.

[codecov-io]

Codecov Report

Merging #3815 into master will decrease coverage by 0.03%.
The diff coverage is 15.38%.

@@            Coverage Diff             @@
##           master    #3815      +/-   ##
==========================================
- Coverage   32.67%   32.63%   -0.04%     
==========================================
  Files         114      114              
  Lines       10754    10809      +55     
==========================================
+ Hits         3514     3528      +14     
- Misses       7240     7281      +41

Impacted Files	Coverage Δ
...s/Data/Implementations/Standard/ChartDataSet.swift	21.05% <15.38%> (-2.29%)	⬇️
Source/Charts/Charts/BarLineChartViewBase.swift	62.19% <0%> (-4.92%)	⬇️
Source/Charts/Charts/ChartViewBase.swift	26.49% <0%> (+3.32%)	⬆️
...Data/Implementations/Standard/ChartDataEntry.swift	60% <0%> (+3.33%)	⬆️

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[jjatie]

I think the deprecations should come in before Chart 4. There are already a ton of conflicts, so it doesn't matter to me

[liuxuan30]

@jjatie while I'm pushing pod trunk, got several warnings from pod:

Validating podspec
 -> Charts (3.2.2)
    - NOTE  | [Charts/Core] xcodebuild:  note: Using new build system
    - NOTE  | [Charts/Core] xcodebuild:  note: Planning build
    - NOTE  | [Charts/Core] xcodebuild:  note: Constructing build description
    - NOTE  | [Charts/Core] xcodebuild:  warning: Skipping code signing because the target does not have an Info.plist file. (in target 'App')
    - WARN  | [Charts/Core] xcodebuild:  Charts/Source/Charts/Data/Implementations/Standard/BarChartDataSet.swift:22:37: warning: 'values' is deprecated: Use `subscript(position:)` instead.
    - WARN  | [Charts/Core] xcodebuild:  Charts/Source/Charts/Data/Implementations/Standard/BarChartDataSet.swift:23:53: warning: 'values' is deprecated: Use `subscript(position:)` instead.
    - WARN  | [Charts/Core] xcodebuild:  Charts/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift:29:9: warning: 'values' is deprecated: Use `subscript(position:)` instead.
    - WARN  | [Charts/Core] xcodebuild:  Charts/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift:36:9: warning: 'values' is deprecated: Use `subscript(position:)` instead.
    - WARN  | [Charts/Core] xcodebuild:  Charts/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift:43:14: warning: 'values' is deprecated: Use `subscript(position:)` instead.
    - WARN  | [Charts/Core] xcodebuild:  Charts/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift:215:19: warning: 'values' is deprecated: Use `subscript(position:)` instead.
    - WARN  | [Charts/Core] xcodebuild:  Charts/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift:216:20: warning: 'values' is deprecated: Use `subscript(position:)` instead.
    - WARN  | [Charts/Core] xcodebuild:  Charts/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift:221:25: warning: 'values' is deprecated: Use `subscript(position:)` instead.
...
[!] The spec did not pass validation, due to 38 warnings (but you can use `--allow-warnings` to ignore them).

I'm using --allow-warnings for trunk push instead. We could start fixing those warnings next time

[jjatie]

Those are warnings intentionally generated by us. We won't be removing values but removing it's public exposure, so it's fine.

[liuxuan30]

but if we don't have to remove values, we need find a way to get rid of the warnings

[jjatie]

    @available(*, deprecated, message: "Use `subscript(position:)` instead.")
    @objc open var values: [ChartDataEntry]
        {
            get { return _values }
            set { _values = newValue }
        }
    internal var _values: [ChartDataEntry]
        {
        didSet
        {
            if isIndirectValuesCall {
                isIndirectValuesCall = false
                return
            }
            notifyDataSetChanged()
        }
    }

and then internally we only reference the internal var.

[liuxuan30]

sure. let's do this with another PR

[liuxuan30]

@jjatie I'm trying to fix the warnings, but I found there are demos using values like

    BarChartDataSet *set = nil;
    if (_chartView.data.dataSetCount > 0)
    {
        set = (BarChartDataSet *)_chartView.data.dataSets[0];
        set.values = yValues;
        [_chartView.data notifyDataChanged];
        [_chartView notifyDataSetChanged];
    }

what you suggest? btw, why do we want to deprecate values?

[liuxuan30]

@jjatie can you get this notification? I didn't have a perfect idea yet, I'm thinking disable deprecate until we find a good way.
Either we add a new API or we don't encourage people to do so anymore. But I suppose. keeping values public is fine