Add Swift version 4.1 to podspec

[larryonoff]

No description provided.

[codecov-io]

Codecov Report

Merging #3608 into 4.0.0 will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##            4.0.0    #3608   +/-   ##
=======================================
  Coverage   30.12%   30.12%           
=======================================
  Files         116      116           
  Lines       13220    13220           
=======================================
  Hits         3982     3982           
  Misses       9238     9238

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[liuxuan30]

Thanks. why should we add this?

Some context: Swift 4.0 branch should be a refactor branch, however @jjatie and I had to take over projects in company, so we postpone the refactor.

Currently, I'm thinking we will finish Xcode 10 update before the refactor. Which means maybe we will move to the latest Swift next month. Adding Swift 4.1 tag in pod might not be valid at that time.

[larryonoff]

@liuxuan30 this's needed for CocoaPods to set correct Swift version in Pods project. In other case the default swift version will be set and workspace may not compile.

[jjatie]

4.1 is the current version and is supported in the Xcode 10 betas. I think we should do this.

[ApoorvKhatreja]

Just FYI, in my Podfile, I have the Charts pod pointed to the 4.0.0 branch, and this change causes pod install to fail.

Podfile:

 pod 'Charts', :git => 'git@github.com:danielgindi/Charts.git', :branch => '4.0.0'

Error message:

Pre-downloading: `Charts` from `git@github.com:danielgindi/Charts.git`, branch `4.0.0`
[!] Failed to load 'Charts' podspec:
[!] Invalid `Charts.podspec` file: undefined method `swift_version=' for #<Pod::Specification name="Charts">.

 #  from /var/folders/2q/hd3_cxdx0ynfl0vh3hy6_8480000gn/T/d20180913-83750-1n0woo3/Charts.podspec:8
 #  -------------------------------------------
 #    s.authors = "Daniel Cohen Gindi", "Philipp Jahoda"
 >    s.swift_version = '4.1'
 #    s.ios.deployment_target = "8.0"
 #  -------------------------------------------

[larryonoff]

@ApoorvKhatreja what CocoaPods version do you use? what version of Xcode?

[ApoorvKhatreja]

@larryonoff

$ pod --version
1.3.1

I have both Xcode 9.4.1 and the Xcode 10 GM installed.

[larryonoff]

@ApoorvKhatreja please update CocoaPods to 1.4.* where swift_version was introduced and better to the latest one 1.5.3.