package.src.util.operation_group.js Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of codemirror Show documentation

Basic configuration for the CodeMirror code editor

The newest version!

import { getHandlers } from "./event.js"

let operationGroup = null

export function pushOperation(op) {
  if (operationGroup) {
    operationGroup.ops.push(op)
  } else {
    op.ownsGroup = operationGroup = {
      ops: [op],
      delayedCallbacks: []
    }
  }
}

function fireCallbacksForOps(group) {
  // Calls delayed callbacks and cursorActivity handlers until no
  // new ones appear
  let callbacks = group.delayedCallbacks, i = 0
  do {
    for (; i < callbacks.length; i++)
      callbacks[i].call(null)
    for (let j = 0; j < group.ops.length; j++) {
      let op = group.ops[j]
      if (op.cursorActivityHandlers)
        while (op.cursorActivityCalled < op.cursorActivityHandlers.length)
          op.cursorActivityHandlers[op.cursorActivityCalled++].call(null, op.cm)
    }
  } while (i < callbacks.length)
}

export function finishOperation(op, endCb) {
  let group = op.ownsGroup
  if (!group) return

  try { fireCallbacksForOps(group) }
  finally {
    operationGroup = null
    endCb(group)
  }
}

let orphanDelayedCallbacks = null

// Often, we want to signal events at a point where we are in the
// middle of some work, but don't want the handler to start calling
// other methods on the editor, which might be in an inconsistent
// state or simply not expect any other events to happen.
// signalLater looks whether there are any handlers, and schedules
// them to be executed when the last operation ends, or, if no
// operation is active, when a timeout fires.
export function signalLater(emitter, type /*, values...*/) {
  let arr = getHandlers(emitter, type)
  if (!arr.length) return
  let args = Array.prototype.slice.call(arguments, 2), list
  if (operationGroup) {
    list = operationGroup.delayedCallbacks
  } else if (orphanDelayedCallbacks) {
    list = orphanDelayedCallbacks
  } else {
    list = orphanDelayedCallbacks = []
    setTimeout(fireOrphanDelayed, 0)
  }
  for (let i = 0; i < arr.length; ++i)
    list.push(() => arr[i].apply(null, args))
}

function fireOrphanDelayed() {
  let delayed = orphanDelayedCallbacks
  orphanDelayedCallbacks = null
  for (let i = 0; i < delayed.length; ++i) delayed[i]()
}