Review: misc improvements

build.gradle

 buildscript {
     repositories {
         mavenLocal()
-        maven { url "https://mirrors.huaweicloud.com/repository/maven" }
+        maven { url 'https://mirrors.huaweicloud.com/repository/maven' }
         jcenter()
         mavenCentral()
         google()
-        maven { url "https://dl.bintray.com/kotlin/kotlin-eap" }
-        maven { url 'https://dl.bintray.com/kotlin/kotlin-dev/'}
+        maven { url 'https://dl.bintray.com/kotlin/kotlin-eap' }
+        maven { url 'https://dl.bintray.com/kotlin/kotlin-dev' }
     }
 
     dependencies {
         classpath 'com.android.tools.build:gradle:3.5.3'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion"
-        classpath("com.github.jengelman.gradle.plugins:shadow:5.2.0")
+        classpath 'com.github.jengelman.gradle.plugins:shadow:5.2.0'
         classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlinVersion"
         classpath "org.jetbrains.kotlinx:atomicfu-gradle-plugin:$atomicFuVersion"
     }
@@ -27,7 +27,9 @@ try {
     } else {
         project.ext.set("isAndroidSDKAvailable", false)
     }
-}catch(Exception e){}
+} catch (Exception ignored) {
+}
+
 allprojects {
     group = "net.mamoe"
     version = getProperty("mirai_version")

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/QQAndroidBot.kt

@@ -75,11 +75,11 @@ internal abstract class QQAndroidBotBase constructor(
 
     // internally visible only
     fun getGroupByUin(uin: Long): Group {
-        return groups.delegate.filteringGetOrNull { (it as GroupImpl).uin == uin } ?: throw NoSuchElementException("Can not found group with ID=${uin}")
+        return groups.delegate.getOrNull(uin) ?: throw NoSuchElementException("Can not found group with ID=${uin}")
     }
 
     fun getGroupByUinOrNull(uin: Long): Group? {
-        return groups.delegate.filteringGetOrNull { (it as GroupImpl).uin == uin }
+        return groups.delegate.getOrNull(uin)
     }
 
     override suspend fun queryGroupList(): Sequence<Long> {

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/ContactList.kt

@@ -16,6 +16,8 @@ import net.mamoe.mirai.utils.*
 
 /**
  * 只读联系人列表, lock-free 实现
+ *
+ * @see ContactList.asSequence
  */
 @UseExperimental(MiraiInternalAPI::class)
 @Suppress("unused")