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Pull sequencer-related callbacks out of execute

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This commit is contained in:
Tim Mickel 2016-06-09 14:23:34 -04:00
parent 9df470255e
commit c21700380f
2 changed files with 69 additions and 125 deletions
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127
src/engine/execute.js
View file

@ -1,7 +1,12 @@
var Thread = require('./thread');
var YieldTimers = require('../util/yieldtimers.js');
var execute = function (sequencer, thread, blockId, isInput) {
/**
* If set, block calls, args, and return values will be logged to the console.
* @const {boolean}
*/
var DEBUG_BLOCK_CALLS = true;
var execute = function (sequencer, thread, blockId) {
var runtime = sequencer.runtime;
// Save the yield timer ID, in case a primitive makes a new one
@ -12,91 +17,8 @@ var execute = function (sequencer, thread, blockId, isInput) {
var opcode = runtime.blocks.getOpcode(blockId);
// Push the current block to the stack
thread.stack.push(blockId);
// Push an empty stack frame, if we need one.
// Might not, if we just popped the stack.
if (thread.stack.length > thread.stackFrames.length) {
thread.stackFrames.push({});
}
var currentStackFrame = thread.stackFrames[thread.stackFrames.length - 1];
/**
* A callback for the primitive to indicate its thread should yield.
* @type {Function}
*/
var threadYieldCallback = function () {
thread.status = Thread.STATUS_YIELD;
};
/**
* A callback for the primitive to indicate its thread is finished
* @type {Function}
*/
var threadDoneCallback = function () {
// Pop the stack and stack frame
thread.stack.pop();
thread.stackFrames.pop();
// If we're not executing an input sub-block,
// mark the thread as done and proceed to the next block.
if (!isInput) {
thread.status = Thread.STATUS_DONE;
// Refresh nextBlock in case it has changed during a yield.
thread.nextBlock = runtime.blocks.getNextBlock(blockId);
}
// Stop showing run feedback in the editor.
runtime.glowBlock(blockId, false);
};
/**
* A callback for the primitive to start hats.
* @todo very hacked...
* Provide a callback that is passed in a block and returns true
* if it is a hat that should be triggered.
* @param {Function} callback Provided callback.
*/
var startHats = function(callback) {
var stacks = runtime.blocks.getStacks();
for (var i = 0; i < stacks.length; i++) {
var stack = stacks[i];
var stackBlock = runtime.blocks.getBlock(stack);
var result = callback(stackBlock);
if (result) {
// Check if the stack is already running
var stackRunning = false;
for (var j = 0; j < runtime.threads.length; j++) {
if (runtime.threads[j].topBlock == stack) {
stackRunning = true;
break;
}
}
if (!stackRunning) {
runtime._pushThread(stack);
}
}
}
};
/**
* Record whether we have switched stack,
* to avoid proceeding the thread automatically.
* @type {boolean}
*/
var switchedStack = false;
/**
* A callback for a primitive to start a substack.
* @type {Function}
*/
var threadStartSubstack = function () {
// Set nextBlock to the start of the substack
var substack = runtime.blocks.getSubstack(blockId);
if (substack && substack.value) {
thread.nextBlock = substack.value;
} else {
thread.nextBlock = null;
}
switchedStack = true;
};
thread.pushStack(blockId);
var currentStackFrame = thread.getLastStackFrame();
// Generate values for arguments (inputs).
var argValues = {};
@ -112,13 +34,10 @@ var execute = function (sequencer, thread, blockId, isInput) {
for (var inputName in inputs) {
var input = inputs[inputName];
var inputBlockId = input.block;
var result = execute(sequencer, thread, inputBlockId, true);
var result = execute(sequencer, thread, inputBlockId);
argValues[input.name] = result;
}
// Start showing run feedback in the editor.
runtime.glowBlock(blockId, true);
if (!opcode) {
console.warn('Could not get opcode for block: ' + blockId);
console.groupEnd();
@ -132,21 +51,24 @@ var execute = function (sequencer, thread, blockId, isInput) {
return;
}
if (sequencer.DEBUG_BLOCK_CALLS) {
if (DEBUG_BLOCK_CALLS) {
console.groupCollapsed('Executing: ' + opcode);
console.log('with arguments: ', argValues);
console.log('and stack frame: ', currentStackFrame);
}
var blockFunctionReturnValue = null;
var primitiveReturnValue = null;
try {
// @todo deal with the return value
blockFunctionReturnValue = blockFunction(argValues, {
yield: threadYieldCallback,
done: threadDoneCallback,
primitiveReturnValue = blockFunction(argValues, {
yield: thread.yield,
done: function() {
sequencer.proceedThread(thread, blockId);
},
timeout: YieldTimers.timeout,
stackFrame: currentStackFrame,
startSubstack: threadStartSubstack,
startHats: startHats
startSubstack: function () {
sequencer.stepToSubstack(thread, blockId);
}
});
}
catch(e) {
@ -159,15 +81,12 @@ var execute = function (sequencer, thread, blockId, isInput) {
if (YieldTimers.timerId > oldYieldTimerId) {
thread.yieldTimerId = YieldTimers.timerId;
}
if (thread.status === Thread.STATUS_RUNNING && !switchedStack) {
// Thread executed without yielding - move to done
threadDoneCallback();
}
if (sequencer.DEBUG_BLOCK_CALLS) {
if (DEBUG_BLOCK_CALLS) {
console.log('ending stack frame: ', currentStackFrame);
console.log('returned: ', blockFunctionReturnValue);
console.log('returned: ', primitiveReturnValue);
console.groupEnd();
}
return primitiveReturnValue;
}
};

67
src/engine/sequencer.js
View file

@ -25,12 +25,6 @@ function Sequencer (runtime) {
*/
Sequencer.WORK_TIME = 10;
/**
* If set, block calls, args, and return values will be logged to the console.
* @const {boolean}
*/
Sequencer.DEBUG_BLOCK_CALLS = true;
/**
* Step through all threads in `this.threads`, running them in order.
* @param {Array.<Thread>} threads List of which threads to step.
@ -65,17 +59,6 @@ Sequencer.prototype.stepThreads = function (threads) {
activeThread.status = Thread.STATUS_RUNNING;
// @todo Deal with the return value
}
// First attempt to pop from the stack
if (activeThread.stack.length > 0 &&
activeThread.nextBlock === null &&
activeThread.status === Thread.STATUS_DONE) {
activeThread.nextBlock = activeThread.stack.pop();
// Don't pop stack frame - we need the data.
// A new one won't be created when we execute.
if (activeThread.nextBlock !== null) {
activeThread.status === Thread.STATUS_RUNNING;
}
}
if (activeThread.nextBlock === null &&
activeThread.status === Thread.STATUS_DONE) {
// Finished with this thread - tell runtime to clean it up.
@ -99,14 +82,56 @@ Sequencer.prototype.stepThread = function (thread) {
// Save the current block and set the nextBlock.
// If the primitive would like to do control flow,
// it can overwrite nextBlock.
var currentBlock = thread.nextBlock;
if (!currentBlock || !this.runtime.blocks.getBlock(currentBlock)) {
var currentBlockId = thread.nextBlock;
if (!currentBlockId || !this.runtime.blocks.getBlock(currentBlockId)) {
thread.status = Thread.STATUS_DONE;
return;
}
thread.nextBlock = this.runtime.blocks.getNextBlock(currentBlock);
// Start showing run feedback in the editor.
this.runtime.glowBlock(currentBlockId, true);
// Execute the block
execute(this, thread, currentBlockId, false);
// If the block executed without yielding, move to done.
if (thread.status === Thread.STATUS_RUNNING && !thread.switchedStack) {
this.proceedThread(thread, currentBlockId);
}
};
execute(this, thread, currentBlock, false);
/**
* Step a thread into a block's substack.
* @param {!Thread} thread Thread object to step to substack.
* @param {string} currentBlockId Block which owns a substack to step to.
*/
Sequencer.prototype.stepToSubstack = function (thread, currentBlockId) {
// Set nextBlock to the start of the substack
var substack = this.runtime.blocks.getSubstack(currentBlockId);
if (substack && substack.value) {
thread.nextBlock = substack.value;
} else {
thread.nextBlock = null;
}
thread.switchedStack = true;
};
/**
* Finish stepping a thread and proceed it to the next block.
* @param {!Thread} thread Thread object to proceed.
* @param {string} currentBlockId Block we are finished with.
*/
Sequencer.prototype.proceedThread = function (thread, currentBlockId) {
// Stop showing run feedback in the editor.
this.runtime.glowBlock(currentBlockId, false);
// Pop the stack and stack frame
thread.popStack();
// Mark the thread as done and proceed to the next block.
thread.status = Thread.STATUS_DONE;
// Refresh nextBlock in case it has changed during a yield.
thread.nextBlock = this.runtime.blocks.getNextBlock(currentBlockId);
// If none is available, attempt to pop from the stack.
// First attempt to pop from the stack
if (!thread.nextBlock && thread.stack.length > 0) {
thread.nextBlock = thread.popStack();
}
};
module.exports = Sequencer;