refactor history into transforms

lib/models/transform.js

@@ -16,13 +16,9 @@ class Transform {
    */
 
   constructor(properties) {
-    const { state, operations = [] } = properties
+    const { state } = properties
     this.state = state
     this.operations = []
-
-    operations.forEach(op => {
-      this.applyOperation(op)
-    })
   }
 
   /**
@@ -40,157 +36,48 @@ class Transform {
    *
    * @param {Object} options
    *   @property {Boolean} isNative
-   *   @property {Boolean} snapshot
+   *   @property {Boolean} merge
+   *   @property {Boolean} save
    * @return {State} state
    */
 
   apply(options = {}) {
+    let { merge, isNative = false, save = true } = options
     let { state, operations } = this
     let { history } = state
     let { undos, redos } = history
+    const previous = undos.peek()
 
     // If there are no operations, abort early.
     if (!operations.length) return state
 
-    // The `isNative` flag allows for natively-handled changes to skip
-    // rerendering the editor for improved performance.
-    const isNative = !!options.isNative
+    // If there's a previous save point, determine if the new operations should
+    // be merged into the previous ones.
+    if (previous && merge == null) {
+      const types = operations.map(op => op.type)
+      const prevTypes = previous.map(op => op.type)
+      const edits = types.filter(type => type != 'set_selection')
+      const prevEdits = prevTypes.filter(type => type != 'set_selection')
+      const onlySelections = types.every(type => type == 'set_selection')
+      const onlyInserts = edits.length && edits.every(type => type == 'insert_text')
+      const onlyRemoves = edits.length && edits.every(type => type == 'remove_text')
+      const prevOnlyInserts = prevEdits.length && prevEdits.every(type => type == 'insert_text')
+      const prevOnlyRemoves = prevEdits.length && prevEdits.every(type => type == 'remove_text')
 
-    // Determine whether we need to create a new snapshot.
-    const shouldSnapshot = options.snapshot == null
-      ? this.shouldSnapshot()
-      : options.snapshot
-
-    // Either create a new snapshot, or push the operations into the previous.
-    if (shouldSnapshot) {
-      const snapshot = { operations }
-      undos = undos.push(snapshot)
-    } else {
-      const snapshot = undos.peek()
-      snapshot.operations = snapshot.operations.concat(operations)
+      merge = (
+        (onlySelections) ||
+        (onlyInserts && prevOnlyInserts) ||
+        (onlyRemoves && prevOnlyRemoves)
+      )
     }
 
-    // Clear the redo stack and constrain the undos stack.
-    if (undos.size > 100) undos = undos.take(100)
-    redos = redos.clear()
-
-    // Update the state.
-    history = history.merge({ undos, redos })
-    state = state.merge({ history, isNative })
-    return state
-  }
-
-  /**
-   * Check whether the current transform operations should create a snapshot.
-   *
-   * @return {Boolean}
-   */
-
-  shouldSnapshot() {
-    const { state, operations } = this
-    const { history, selection } = state
-    const { undos, redos } = history
-    const previous = undos.peek()
-
-    // If there isn't a previous state, snapshot.
-    if (!previous) return true
-
-    const types = operations.map(op => op.type)
-    const prevTypes = previous.operations.map(op => op.type)
-    const edits = types.filter(type => type != 'set_selection')
-    const prevEdits = prevTypes.filter(type => type != 'set_selection')
-
-    const onlySelections = types.every(type => type == 'set_selection')
-    const onlyInsert = edits.every(type => type == 'insert_text')
-    const onlyRemove = edits.every(type => type == 'remove_text')
-    const prevOnlySelections = prevTypes.every(type => type == 'set_selection')
-    const prevOnlyInsert = prevEdits.every(type => type == 'insert_text')
-    const prevOnlyRemove = prevEdits.every(type => type == 'remove_text')
-
-    // If the only operations applied are selection operations, or if the
-    // current operations are all text editing, don't snapshot.
-    if (
-      (onlySelections) ||
-      (!prevOnlySelections && onlyInsert && prevOnlyInsert) ||
-      (!prevOnlySelections && onlyRemove && prevOnlyRemove)
-    ) {
-      return false
+    // Save the new operations.
+    if (save || !previous) {
+      this.save({ merge })
     }
 
-    // Otherwise, snapshot.
-    return true
-  }
-
-  /**
-   * Redo to the next state in the history.
-   *
-   * @return {State} state
-   */
-
-  redo() {
-    let { state } = this
-    let { history } = state
-    let { undos, redos } = history
-
-    // If there's no next snapshot, return the current state.
-    let next = redos.peek()
-    if (!next) return state
-
-    // Shift the next state into the undo stack.
-    redos = redos.pop()
-    undos = undos.push(next)
-
-    // Replay the next operations.
-    const { operations } = next
-    operations.forEach(op => {
-      this.applyOperation(op)
-    })
-
-    // Update the state's history and force `isNative` to false.
-    history = history.merge({ undos, redos })
-    state = this.state.merge({
-      history,
-      isNative: false,
-    })
-
-    return state
-  }
-
-  /**
-   * Undo the previous operations in the history.
-   *
-   * @return {State} state
-   */
-
-  undo() {
-    let { state } = this
-    let { history } = state
-    let { undos, redos } = history
-
-    // If there's no previous snapshot, return the current state.
-    let previous = undos.peek()
-    if (!previous) return state
-
-    // Shift the previous operations into the redo stack.
-    undos = undos.pop()
-    redos = redos.push(previous)
-
-    // Replay the inverse of the previous operations.
-    const operations = previous.operations.slice().reverse()
-    operations.forEach(op => {
-      op.inverse.forEach(inv => {
-        this.applyOperation(inv)
-      })
-    })
-
-    // Update the state's history and force `isNative` to false.
-    history = history.merge({ undos, redos })
-    state = this.state.merge({
-      history,
-      isNative: false,
-    })
-
-    return state
+    // Return the new state with the `isNative` flag set.
+    return this.state.merge({ isNative: !!isNative })
   }
 
 }

lib/plugins/core.js

@@ -467,6 +467,7 @@ function Plugin(options = {}) {
     return state
       .transform()
       .redo()
+      .apply({ save: false })
   }
 
   /**
@@ -486,6 +487,7 @@ function Plugin(options = {}) {
     return state
       .transform()
       [data.isShift ? 'redo' : 'undo']()
+      .apply({ save: false })
   }
 
   /**

lib/transforms/apply-operation.js

@@ -1,6 +1,15 @@
 
+import Debug from 'debug'
 import uid from '../utils/uid'
 
+/**
+ * Debug.
+ *
+ * @type {Function}
+ */
+
+const debug = Debug('slate:operation')
+
 /**
  * Operations.
  *
@@ -42,6 +51,8 @@ export function applyOperation(transform, operation) {
     throw new Error(`Unknown operation type: "${type}".`)
   }
 
+  debug(type, operation)
+
   transform.state = fn(state, operation)
   transform.operations = operations.concat([operation])
   return transform

lib/transforms/history.js

@@ -0,0 +1,112 @@
+
+/**
+ * Redo to the next state in the history.
+ *
+ * @param {Transform} transform
+ * @return {Transform}
+ */
+
+export function redo(transform) {
+  let { state } = transform
+  let { history } = state
+  let { undos, redos } = history
+
+  // If there's no next snapshot, abort.
+  let next = redos.peek()
+  if (!next) return transform
+
+  // Shift the next state into the undo stack.
+  redos = redos.pop()
+  undos = undos.push(next)
+
+  // Replay the next operations.
+  next.forEach(op => {
+    transform.applyOperation(op)
+  })
+
+  // Update the history.
+  state = transform.state
+  history = history.merge({ undos, redos })
+  state = state.merge({ history })
+
+  // Update the transform.
+  transform.state = state
+  return transform
+}
+
+/**
+ * Save the operations into the history.
+ *
+ * @param {Transform} transform
+ * @param {Object} options
+ * @return {Transform}
+ */
+
+export function save(transform, options = {}) {
+  const { merge = false } = options
+  let { state, operations } = transform
+  let { history } = state
+  let { undos, redos } = history
+
+  // If there are no operations, abort.
+  if (!operations.length) return transform
+
+  // Create a new save point or merge the operations into the previous one.
+  if (merge) {
+    let previous = undos.peek()
+    undos = undos.pop()
+    previous = previous.concat(operations)
+    undos = undos.push(previous)
+  } else {
+    undos = undos.push(operations)
+  }
+
+  // Clear the redo stack and constrain the undos stack.
+  if (undos.size > 100) undos = undos.take(100)
+  redos = redos.clear()
+
+  // Update the state.
+  history = history.merge({ undos, redos })
+  state = state.merge({ history })
+
+  // Update the transform.
+  transform.state = state
+  return transform
+}
+
+/**
+ * Undo the previous operations in the history.
+ *
+ * @param {Transform} transform
+ * @return {Transform}
+ */
+
+export function undo(transform) {
+  let { state } = transform
+  let { history } = state
+  let { undos, redos } = history
+
+  // If there's no previous snapshot, abort.
+  let previous = undos.peek()
+  if (!previous) return transform
+
+  // Shift the previous operations into the redo stack.
+  undos = undos.pop()
+  redos = redos.push(previous)
+
+  // Replay the inverse of the previous operations.
+  previous.slice().reverse().forEach(op => {
+    op.inverse.forEach(inv => {
+      transform.applyOperation(inv)
+    })
+  })
+
+  // Update the history.
+  state = transform.state
+  history = history.merge({ undos, redos })
+  state = state.merge({ history })
+
+  // Update the transform.
+  transform.state = state
+  return transform
+}

lib/transforms/index.js

@@ -135,6 +135,16 @@ import {
   normalizeSelection,
 } from './normalize'
 
+/**
+ * History.
+ */
+
+import {
+  redo,
+  save,
+  undo,
+} from './history'
+
 /**
  * Export.
  *
@@ -265,4 +275,12 @@ export default {
   normalizeDocument,
   normalizeSelection,
 
+  /**
+   * History.
+   */
+
+  redo,
+  save,
+  undo,
+
 }