fix(core): not working first plugin when icon option enabled

[plag]

Hello! Just got not working plugin when enable icon option.

Problem:
not working config:

{
  icon: true,
  plugins: [ { removeDesc: false } ]
}

working config:

{
  icon: true,
  plugins: [ {}, { removeDesc: false } ]
}

Solution: add lodash merge function for concat arrays instead merge them and add test for it.

[codecov]

Codecov Report

Merging #137 into master will decrease coverage by 0.2%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #137      +/-   ##
==========================================
- Coverage   88.75%   88.55%   -0.21%     
==========================================
  Files          25       26       +1     
  Lines         418      428      +10     
  Branches      112      100      -12     
==========================================
+ Hits          371      379       +8     
- Misses         34       42       +8     
+ Partials       13        7       -6

Impacted Files	Coverage Δ
packages/core/src/plugins/mergeConfigs.js	80% <100%> (ø)
packages/core/src/plugins/svgo.js	100% <100%> (ø)	⬆️
packages/core/src/plugins/h2x.js	96.29% <0%> (ø)	⬆️
packages/core/src/h2x/replaceAttrValues.js	72.72% <0%> (ø)	⬆️
packages/core/src/h2x/svgAttributes.js	76.92% <0%> (ø)	⬆️
packages/core/src/templates/reactNativeTemplate.js	76.66% <0%> (ø)	⬆️
packages/core/src/h2x/removeDimensions.js	83.33% <0%> (ø)	⬆️

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[emmenko]

Ah nice, we bumped into the same problem today as well!

Thanks for the PR, that should fix the problem yes 🙌

One minor suggestion maybe: how about extracting the "config merging" into a separate function and test that? Relying on an SVG snapshot to test merged configs is kind of not intuitive. I/we can also open up a new PR to improve the testing if we don't want to do that in this PR.
WDYT?

[emmenko]

👌

[emmenko]

Nitpick: can't we use Array.isArray?

[emmenko]

Nitpick: like suggested, I would extract the "merging" into a separate function and test that in isolation to make sure the "merged" config is correct.

[plag]

@emmenko thank you for comments! just make improvements on your suggestions! what about it?

[emmenko]

Cool, thanks! Much better now 👌
Let's see what the author has to say about it 😇

PS: can you run prettier on the changed/test files? The formatting looks weird.

[plag]

@emmenko sorry for formatting! done with prettier.

[gregberge]

Awesome thanks 🙏 !