housekeeping: factor out components for easier BaseLayout reuse (#4604)

* improve: wrap schemes to encapsulate rendering logic
* improve: wrap filter to encapsulate rendering logic
* improve: wrap info section to encapsulate rendering logic
* improve: wrap servers plugin to encapsulate rendering logic
* improve: added tests for schemes-wrapper rendering logic
* improve: added tests for info-wrapper rendering logic, also do not render info if info is undefined
* improve: added tests for filter rendering logic
* improve: added tests for servers-wrapper rendering logic
* `InfoWrapper` -> `InfoContainer`
* add `containers` alias to Babel configuration
* `SchemesWrapper` -> `SchemesContainer`
* drop `container` from container file names
* `ServersWrapper` -> `ServersContainer`
* `Filter` -> `FilterContainer`
* follow `core/containers` pattern in BasePreset

test/components/filter.js

@@ -0,0 +1,65 @@
+
+/* eslint-env mocha */
+import React from "react"
+import expect from "expect"
+import { mount } from "enzyme"
+import FilterContainer from "containers/filter"
+import { Col } from "components/layout-utils"
+
+describe("<FilterContainer/>", function(){
+
+  const mockedProps = {
+    specSelectors: {
+      loadingStatus() {}
+    },
+    layoutSelectors: {
+      currentFilter() {}
+    },
+    getComponent: () => {return Col}
+  }
+
+  it("renders FilterContainer if filter is provided", function(){
+
+    // Given
+    let props = {...mockedProps}
+    props.layoutSelectors = {...mockedProps.specSelectors}
+    props.layoutSelectors.currentFilter = function() {return true}
+
+    // When
+    let wrapper = mount(<FilterContainer {...props}/>)
+
+    // Then
+    const renderedColInsideFilter = wrapper.find(Col)
+    expect(renderedColInsideFilter.length).toEqual(1)
+  })
+
+  it("does not render FilterContainer if filter is null", function(){
+
+    // Given
+    let props = {...mockedProps}
+    props.layoutSelectors = {...mockedProps.specSelectors}
+    props.layoutSelectors.currentFilter = function() {return null}
+
+    // When
+    let wrapper = mount(<FilterContainer {...props}/>)
+
+    // Then
+    const renderedColInsideFilter = wrapper.find(Col)
+    expect(renderedColInsideFilter.length).toEqual(0)
+  })
+
+  it("does not render FilterContainer if filter is false", function(){
+
+    // Given
+    let props = {...mockedProps}
+    props.layoutSelectors = {...mockedProps.specSelectors}
+    props.layoutSelectors.currentFilter = function() {return false}
+
+    // When
+    let wrapper = mount(<FilterContainer {...props}/>)
+
+    // Then
+    const renderedColInsideFilter = wrapper.find(Col)
+    expect(renderedColInsideFilter.length).toEqual(0)
+  })
+})