ktx: Add extension method: Uri.hostWithoutCommonPrefixes.

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package mozilla.components.support.ktx.android.net

import android.net.Uri

/**

 * Returns the host without common prefixes like "www" or "m".

 */

@Suppress("MagicNumber")

val Uri.hostWithoutCommonPrefixes: String?

    get() {

        val host = host ?: return null

        return when {

            host.startsWith("www.") -> host.substring(4)

            host.startsWith("mobile.") -> host.substring(7)

            host.startsWith("m.") -> host.substring(2)

            else -> host

        }

    }

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package mozilla.components.support.ktx.android.net

import mozilla.components.support.ktx.kotlin.toUri

import org.junit.Assert.assertEquals

import org.junit.Assert.assertNull

import org.junit.Test

import org.junit.runner.RunWith

import org.robolectric.RobolectricTestRunner

@RunWith(RobolectricTestRunner::class)

class UriTest {

    @Test

    fun hostWithoutCommonPrefixes() {

        assertEquals(

            "mozilla.org",

            "https://www.mozilla.org".toUri().hostWithoutCommonPrefixes)

        assertEquals(

            "twitter.com",

            "https://mobile.twitter.com/home".toUri().hostWithoutCommonPrefixes)

        assertNull("".toUri().hostWithoutCommonPrefixes)

        assertEquals(

            "",

            "http://".toUri().hostWithoutCommonPrefixes)

        assertEquals(

            "facebook.com",

            "https://m.facebook.com/".toUri().hostWithoutCommonPrefixes)

        assertEquals(

            "github.com",

            "https://github.com/mozilla-mobile/android-components".toUri().hostWithoutCommonPrefixes)

    }

}