Merge pull request #248 from InsanusMokrassar/0.18.1

0.18.1

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## 0.18.1
+
+* `Common`:
+    * Add `MapDiff`
+* `Coroutines`:
+    * Add `SmartMutex`
+
 ## 0.18.0
 
 **ALL PREVIOUSLY DEPRECATED FUNCTIONALITY HAVE BEEN REMOVED**

common/src/commonMain/kotlin/dev/inmo/micro_utils/common/DiffUtils.kt

@@ -200,20 +200,18 @@ inline fun <T> Iterable<T>.calculateStrictDiff(
 ) = calculateDiff(other, strictComparison = true)
 
 /**
- * This method call [calculateDiff] with strict mode [strictComparison] and then apply differences to [this]
- * mutable list
+ * Applies [diff] to [this] [MutableList]
  */
 fun <T> MutableList<T>.applyDiff(
-    source: Iterable<T>,
-    strictComparison: Boolean = false
-): Diff<T> = calculateDiff(source, strictComparison).also {
-    for (i in it.removed.indices.sortedDescending()) {
-        removeAt(it.removed[i].index)
+    diff: Diff<T>
+) {
+    for (i in diff.removed.indices.sortedDescending()) {
+        removeAt(diff.removed[i].index)
     }
-    it.added.forEach { (i, t) ->
+    diff.added.forEach { (i, t) ->
         add(i, t)
     }
-    it.replaced.forEach { (_, new) ->
+    diff.replaced.forEach { (_, new) ->
         set(new.index, new.value)
     }
 }
@@ -222,17 +220,30 @@ fun <T> MutableList<T>.applyDiff(
  * This method call [calculateDiff] with strict mode [strictComparison] and then apply differences to [this]
  * mutable list
  */
+fun <T> MutableList<T>.applyDiff(
+    source: Iterable<T>,
+    strictComparison: Boolean = false
+): Diff<T> = calculateDiff(source, strictComparison).also {
+    applyDiff(it)
+}
+
+/**
+ * This method call [calculateDiff] and then apply differences to [this]
+ * mutable list
+ */
 fun <T> MutableList<T>.applyDiff(
     source: Iterable<T>,
     comparisonFun: (T?, T?) -> Boolean
 ): Diff<T> = calculateDiff(source, comparisonFun).also {
-    for (i in it.removed.indices.sortedDescending()) {
-        removeAt(it.removed[i].index)
-    }
-    it.added.forEach { (i, t) ->
-        add(i, t)
-    }
-    it.replaced.forEach { (_, new) ->
-        set(new.index, new.value)
-    }
+    applyDiff(it)
 }
+
+/**
+ * Reverse [this] [Diff]. Result will contain [Diff.added] on [Diff.removed] (and vice-verse), all the
+ * [Diff.replaced] values will be reversed too
+ */
+fun <T> Diff<T>.reversed() = Diff(
+    removed = added,
+    replaced = replaced.map { it.second to it.first },
+    added = removed
+)

common/src/commonMain/kotlin/dev/inmo/micro_utils/common/MapDiff.kt

@@ -0,0 +1,135 @@
+package dev.inmo.micro_utils.common
+
+/**
+ * Contains diff based on the comparison of objects with the same [K].
+ *
+ * @param removed Contains map with keys removed from parent map
+ * @param changed Contains map with keys values changed new map in comparison with old one
+ * @param added Contains map with new keys and values
+ */
+data class MapDiff<K, V> @Warning(warning) constructor(
+    val removed: Map<K, V>,
+    val changed: Map<K, Pair<V, V>>,
+    val added: Map<K, V>
+) {
+    fun isEmpty() = removed.isEmpty() && changed.isEmpty() && added.isEmpty()
+    inline fun isNotEmpty() = !isEmpty()
+
+    companion object {
+        private const val warning = "This feature can be changed without any warranties. Use with caution and only in case you know what you are doing"
+        fun <K, V> empty() = MapDiff<K, V>(emptyMap(), emptyMap(), emptyMap())
+    }
+}
+
+private inline fun <K, V> createCompareFun(
+    strictComparison: Boolean
+): (K, V, V) -> Boolean = if (strictComparison) {
+    { _, first, second -> first === second }
+} else {
+    { _, first, second -> first == second }
+}
+
+/**
+ * Compare [this] [Map] with the [other] one in principle when [other] is newer than [this]
+ *
+ * @param compareFun Will be used to determine changed values
+ */
+fun <K, V> Map<K, V>.diff(
+    other: Map<K, V>,
+    compareFun: (K, V, V) -> Boolean
+): MapDiff<K, V> {
+    val removed: Map<K, V> = (keys - other.keys).associateWith {
+        getValue(it)
+    }
+    val added: Map<K, V> = (other.keys - keys).associateWith {
+        other.getValue(it)
+    }
+    val changed = keys.intersect(other.keys).mapNotNull {
+        val old = getValue(it)
+        val new = other.getValue(it)
+        if (compareFun(it, old, new)) {
+            return@mapNotNull null
+        } else {
+            it to (old to new)
+        }
+    }.toMap()
+
+    return MapDiff(
+        removed,
+        changed,
+        added
+    )
+}
+
+/**
+ * Compare [this] [Map] with the [other] one in principle when [other] is newer than [this]
+ *
+ * @param strictComparison If true, will use strict (===) comparison for the values' comparison. Otherwise, standard
+ * `equals` will be used
+ */
+fun <K, V> Map<K, V>.diff(
+    other: Map<K, V>,
+    strictComparison: Boolean = false
+): MapDiff<K, V> = diff(
+    other,
+    compareFun = createCompareFun(strictComparison)
+)
+
+/**
+ * Will apply [mapDiff] to [this] [MutableMap]
+ */
+fun <K, V> MutableMap<K, V>.applyDiff(
+    mapDiff: MapDiff<K, V>
+) {
+    mapDiff.apply {
+        removed.keys.forEach { remove(it) }
+        changed.forEach { (k, oldNew) ->
+            put(k, oldNew.second)
+        }
+        added.forEach { (k, new) ->
+            put(k, new)
+        }
+    }
+}
+
+/**
+ * Will apply changes with [from] map into [this] one
+ *
+ * @param compareFun Will be used to determine changed values
+ *
+ * @return [MapDiff] applied to [this] [MutableMap]
+ */
+fun <K, V> MutableMap<K, V>.applyDiff(
+    from: Map<K, V>,
+    compareFun: (K, V, V) -> Boolean
+): MapDiff<K, V> {
+    return diff(from, compareFun).also {
+        applyDiff(it)
+    }
+}
+
+/**
+ * Will apply changes with [from] map into [this] one
+ *
+ * @param strictComparison If true, will use strict (===) comparison for the values' comparison. Otherwise, standard
+ * `equals` will be used
+ *
+ * @return [MapDiff] applied to [this] [MutableMap]
+ */
+fun <K, V> MutableMap<K, V>.applyDiff(
+    from: Map<K, V>,
+    strictComparison: Boolean = false
+): MapDiff<K, V> = applyDiff(
+    from,
+    compareFun = createCompareFun(strictComparison)
+)
+
+/**
+ * Reverse [this] [MapDiff]. Result will contain [MapDiff.added] on [MapDiff.removed] (and vice-verse), all the
+ * [MapDiff.changed] values will be reversed too
+ */
+fun <K, V> MapDiff<K, V>.reversed(): MapDiff<K, V> = MapDiff(
+    removed = added,
+    changed = changed.mapValues { (_, oldNew) -> oldNew.second to oldNew.first },
+    added = removed
+)

coroutines/src/commonMain/kotlin/dev/inmo/micro_utils/coroutines/SmartMutex.kt

@@ -0,0 +1,136 @@
+package dev.inmo.micro_utils.coroutines
+
+import kotlinx.coroutines.currentCoroutineContext
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import kotlin.contracts.ExperimentalContracts
+import kotlin.contracts.InvocationKind
+import kotlin.contracts.contract
+
+/**
+ * It is interface which will work like classic [Mutex], but in difference have [lockStateFlow] for listening of the
+ * [SmartMutex] state.
+ *
+ * There is [Mutable] and [Immutable] realizations. In case you are owner and manager current state of lock, you need
+ * [Mutable] [SmartMutex]. Otherwise, [Immutable].
+ *
+ * Any [Mutable] [SmartMutex] may produce its [Immutable] variant which will contains [lockStateFlow] equal to its
+ * [Mutable] creator
+ */
+sealed interface SmartMutex {
+    val lockStateFlow: StateFlow<Boolean>
+
+    /**
+     * * True - locked
+     * * False - unlocked
+     */
+    val isLocked: Boolean
+        get() = lockStateFlow.value
+
+    /**
+     * Immutable variant of [SmartMutex]. In fact will depend on the owner of [lockStateFlow]
+     */
+    class Immutable(override val lockStateFlow: StateFlow<Boolean>) : SmartMutex
+
+    /**
+     * Mutable variant of [SmartMutex]. With that variant you may [lock] and [unlock]. Besides, you may create
+     * [Immutable] variant of [this] instance with [immutable] factory
+     *
+     * @param locked Preset state of [isLocked] and its internal [_lockStateFlow]
+     */
+    class Mutable(locked: Boolean = false) : SmartMutex {
+        private val _lockStateFlow = MutableStateFlow<Boolean>(locked)
+        override val lockStateFlow: StateFlow<Boolean> = _lockStateFlow.asStateFlow()
+
+        private val internalChangesMutex = Mutex()
+
+        fun immutable() = Immutable(lockStateFlow)
+
+        /**
+         * Holds call until this [SmartMutex] will be re-locked. That means that while [isLocked] == true, [holds] will
+         * wait for [isLocked] == false and then try to lock
+         */
+        suspend fun lock() {
+            do {
+                waitUnlock()
+                val shouldContinue = internalChangesMutex.withLock {
+                    if (_lockStateFlow.value) {
+                        true
+                    } else {
+                        _lockStateFlow.value = true
+                        false
+                    }
+                }
+            } while (shouldContinue && currentCoroutineContext().isActive)
+        }
+
+        /**
+         * Will try to lock this [SmartMutex] immediataly
+         *
+         * @return True if lock was successful. False otherwise
+         */
+        suspend fun tryLock(): Boolean {
+            return if (!_lockStateFlow.value) {
+                internalChangesMutex.withLock {
+                    if (!_lockStateFlow.value) {
+                        _lockStateFlow.value = true
+                        true
+                    } else {
+                        false
+                    }
+                }
+            } else {
+                false
+            }
+        }
+
+        /**
+         * If [isLocked] == true - will change it to false and return true. If current call will not unlock this
+         * [SmartMutex] - false
+         */
+        suspend fun unlock(): Boolean {
+            return if (_lockStateFlow.value) {
+                internalChangesMutex.withLock {
+                    if (_lockStateFlow.value) {
+                        _lockStateFlow.value = false
+                        true
+                    } else {
+                        false
+                    }
+                }
+            } else {
+                false
+            }
+        }
+    }
+}
+
+/**
+ * Will call [SmartMutex.Mutable.lock], then execute [action] and return the result after [SmartMutex.Mutable.unlock]
+ */
+@OptIn(ExperimentalContracts::class)
+suspend inline fun <T> SmartMutex.Mutable.withLock(action: () -> T): T {
+    contract {
+        callsInPlace(action, InvocationKind.EXACTLY_ONCE)
+    }
+
+    lock()
+    try {
+        return action()
+    } finally {
+        unlock()
+    }
+}
+
+/**
+ * Will wait until the [SmartMutex.lockStateFlow] of [this] instance will be false.
+ *
+ * Anyway, after the end of this block there are no any guaranties that [SmartMutex.isLocked] == false due to the fact
+ * that some other parties may lock it again
+ */
+suspend fun SmartMutex.waitUnlock() = lockStateFlow.first { !it }

gradle.properties

@@ -14,5 +14,5 @@ crypto_js_version=4.1.1
 # Project data
 
 group=dev.inmo
-version=0.18.0
-android_code_version=191
+version=0.18.1
+android_code_version=192