Fixed bug that caused WebP parameter value 0 to be ignored

[AaaK00]

Found out that zero cannot be given as parameter to WebP options. For example, code:

let options = [.encodeWebPMethod: 0, .encodeWebPAlphaCompression: 100]
let data = SDImageWebPCoder.shared.encodedData(with: image, format: .webP, options: options)

Does not work correctly. Default value for WebP method (4) is used instead of 0.

Issue is caused by the fact that comparison

if ([options[SDImageCoderEncodeWebPMethod] intValue])

results to false when intValue is 0.

Fixed by changing the logic of how it is concluded whether value for certain option has been provided. Also updated unit tests so they catch similar issues in future.

[codecov]

Codecov Report

Merging #52 (415e6b6) into master (864a71e) will decrease coverage by 0.25%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master      #52      +/-   ##
==========================================
- Coverage   77.36%   77.11%   -0.26%     
==========================================
  Files           2        2              
  Lines         813      804       -9     
==========================================
- Hits          629      620       -9     
  Misses        184      184              

Flag	Coverage Δ
ios	77.11% <100.00%> (-0.26%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
SDWebImageWebPCoder/Classes/SDImageWebPCoder.m	77.00% <100.00%> (-0.26%)	⬇️

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[dreampiggy]

That helper method getIntValueFor:defaultValue:options: looks really strange. Not a good design for SDK development. (Only works in this context, why not more generic)

Use something like this:

static int GetIntValueForKey(NSDictionary * _Nonnull dictionary, NSString * _Nonnull key, int defaultValue) {
   // ... same implementation
}

Or even a extension to NSDictionary, but I think since SDWebImageWebPCoder is simple codec wrapper. Adding extension to NSDictionary class will increase binary size and have to use something like prefix style API sd_intValueForKey:, which I dislike...

So a single inline or static C function is better.

[AaaK00]

That helper method getIntValueFor:defaultValue:options: looks really strange. Not a good design for SDK development. (Only works in this context, why not more generic)

Use something like this:

static int GetIntValueForKey(NSDictionary * _Nonnull dictionary, NSString * _Nonnull key, int defaultValue) {
   // ... same implementation
}

Or even a extension to NSDictionary, but I think since SDWebImageWebPCoder is simple codec wrapper. Adding extension to NSDictionary class will increase binary size and have to use something like prefix style API sd_intValueForKey:, which I dislike...

So a single inline or static C function is better.

Yeap, good point. Probably better to use plain static C function. Better now?

[dreampiggy]

LGTM now. I'll merge and release new version.

[dreampiggy]

Released v0.8.1