Folder restructure (#6304)

* Remove ui/app/keychains/

* Remove ui/app/img/ (unused images)

* Move conversion-util to helpers/utils/

* Move token-util to helpers/utils/

* Move /helpers/*.js inside /helpers/utils/

* Move util tests inside /helpers/utils/

* Renameand move confirm-transaction/util.js to helpers/utils/

* Move higher-order-components to helpers/higher-order-components/

* Move infura-conversion.json to helpers/constants/

* Move all utility functions to helpers/utils/

* Move pages directory to top-level

* Move all constants to helpers/constants/

* Move metametrics inside helpers/

* Move app and root inside pages/

* Move routes inside helpers/

* Re-organize ducks/

* Move reducers to ducks/

* Move selectors inside selectors/

* Move test out of test folder

* Move action, reducer, store inside store/

* Move ui components inside ui/

* Move UI components inside ui/

* Move connected components inside components/app/

* Move i18n-helper inside helpers/

* Fix unit tests

* Fix unit test

* Move pages components

* Rename routes component

* Move reducers to ducks/index

* Fix bad path in unit test

1 files changed, 106 insertions, 0 deletions

diff --git a/ui/app/helpers/higher-order-components/with-token-tracker/with-token-tracker.component.js b/ui/app/helpers/higher-order-components/with-token-tracker/with-token-tracker.component.js
new file mode 100644
index 000000000..36f6a6efd
--- /dev/null
+++ b/ui/app/helpers/higher-order-components/with-token-tracker/with-token-tracker.component.js
@@ -0,0 +1,106 @@
+import React, { Component } from 'react'
+import PropTypes from 'prop-types'
+import TokenTracker from 'eth-token-tracker'
+
+export default function withTokenTracker (WrappedComponent) {
+  return class TokenTrackerWrappedComponent extends Component {
+    static propTypes = {
+      userAddress: PropTypes.string.isRequired,
+      token: PropTypes.object.isRequired,
+    }
+
+    constructor (props) {
+      super(props)
+
+      this.state = {
+        string: '',
+        symbol: '',
+        error: null,
+      }
+
+      this.tracker = null
+      this.updateBalance = this.updateBalance.bind(this)
+      this.setError = this.setError.bind(this)
+    }
+
+    componentDidMount () {
+      this.createFreshTokenTracker()
+    }
+
+    componentDidUpdate (prevProps) {
+      const { userAddress: newAddress, token: { address: newTokenAddress } } = this.props
+      const { userAddress: oldAddress, token: { address: oldTokenAddress } } = prevProps
+
+      if ((oldAddress === newAddress) && (oldTokenAddress === newTokenAddress)) {
+        return
+      }
+
+      if ((!oldAddress || !newAddress) && (!oldTokenAddress || !newTokenAddress)) {
+        return
+      }
+
+      this.createFreshTokenTracker()
+    }
+
+    componentWillUnmount () {
+      this.removeListeners()
+    }
+
+    createFreshTokenTracker () {
+      this.removeListeners()
+
+      if (!global.ethereumProvider) {
+        return
+      }
+
+      const { userAddress, token } = this.props
+
+      this.tracker = new TokenTracker({
+        userAddress,
+        provider: global.ethereumProvider,
+        tokens: [token],
+        pollingInterval: 8000,
+      })
+
+      this.tracker.on('update', this.updateBalance)
+      this.tracker.on('error', this.setError)
+
+      this.tracker.updateBalances()
+        .then(() => this.updateBalance(this.tracker.serialize()))
+        .catch(error => this.setState({ error: error.message }))
+    }
+
+    setError (error) {
+      this.setState({ error })
+    }
+
+    updateBalance (tokens = []) {
+      if (!this.tracker.running) {
+        return
+      }
+      const [{ string, symbol }] = tokens
+      this.setState({ string, symbol, error: null })
+    }
+
+    removeListeners () {
+      if (this.tracker) {
+        this.tracker.stop()
+        this.tracker.removeListener('update', this.updateBalance)
+        this.tracker.removeListener('error', this.setError)
+      }
+    }
+
+    render () {
+      const { string, symbol, error } = this.state
+
+      return (
+        <WrappedComponent
+          { ...this.props }
+          string={string}
+          symbol={symbol}
+          error={error}
+        />
+      )
+    }
+  }
+}