javascript.js

/**
 * Visual Blocks Language
 *
 * Copyright 2012 Google Inc.
 * http://blockly.googlecode.com/
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @fileoverview Helper functions for generating JavaScript for blocks.
 * @author fraser@google.com (Neil Fraser)
 */
'use strict';

Blockly.JavaScript = new Blockly.Generator('JavaScript');

/**
 * List of illegal variable names.
 * This is not intended to be a security feature.  Blockly is 100% client-side,
 * so bypassing this list is trivial.  This is intended to prevent users from
 * accidentally clobbering a built-in object or function.
 * @private
 */
// Blockly.JavaScript.addReservedWords(
//     'Blockly,' +  // In case JS is evaled in the current window.
//     // https://developer.mozilla.org/en/JavaScript/Reference/Reserved_Words
//     'break,case,catch,continue,debugger,default,delete,do,else,finally,for,function,if,in,instanceof,new,return,switch,this,throw,try,typeof,var,void,while,with,' +
//     'class,enum,export,extends,import,super,implements,interface,let,package,private,protected,public,static,yield,' +
//     'const,null,true,false,' +
//     // https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects
//     'Array,ArrayBuffer,Boolean,Date,decodeURI,decodeURIComponent,encodeURI,encodeURIComponent,Error,eval,EvalError,Float32Array,Float64Array,Function,Infinity,Int16Array,Int32Array,Int8Array,isFinite,isNaN,Iterator,JSON,Math,NaN,Number,Object,parseFloat,parseInt,RangeError,ReferenceError,RegExp,StopIteration,String,SyntaxError,TypeError,Uint16Array,Uint32Array,Uint8Array,Uint8ClampedArray,undefined,uneval,URIError,' +
//     // https://developer.mozilla.org/en/DOM/window
//     'applicationCache,closed,Components,content,_content,controllers,crypto,defaultStatus,dialogArguments,directories,document,frameElement,frames,fullScreen,globalStorage,history,innerHeight,innerWidth,length,location,locationbar,localStorage,menubar,messageManager,mozAnimationStartTime,mozInnerScreenX,mozInnerScreenY,mozPaintCount,name,navigator,opener,outerHeight,outerWidth,pageXOffset,pageYOffset,parent,performance,personalbar,pkcs11,returnValue,screen,screenX,screenY,scrollbars,scrollMaxX,scrollMaxY,scrollX,scrollY,self,sessionStorage,sidebar,status,statusbar,toolbar,top,URL,window,' +
//     'addEventListener,alert,atob,back,blur,btoa,captureEvents,clearImmediate,clearInterval,clearTimeout,close,confirm,disableExternalCapture,dispatchEvent,dump,enableExternalCapture,escape,find,focus,forward,GeckoActiveXObject,getAttention,getAttentionWithCycleCount,getComputedStyle,getSelection,home,matchMedia,maximize,minimize,moveBy,moveTo,mozRequestAnimationFrame,open,openDialog,postMessage,print,prompt,QueryInterface,releaseEvents,removeEventListener,resizeBy,resizeTo,restore,routeEvent,scroll,scrollBy,scrollByLines,scrollByPages,scrollTo,setCursor,setImmediate,setInterval,setResizable,setTimeout,showModalDialog,sizeToContent,stop,unescape,updateCommands,XPCNativeWrapper,XPCSafeJSObjectWrapper,' +
//     'onabort,onbeforeunload,onblur,onchange,onclick,onclose,oncontextmenu,ondevicemotion,ondeviceorientation,ondragdrop,onerror,onfocus,onhashchange,onkeydown,onkeypress,onkeyup,onload,onmousedown,onmousemove,onmouseout,onmouseover,onmouseup,onmozbeforepaint,onpaint,onpopstate,onreset,onresize,onscroll,onselect,onsubmit,onunload,onpageshow,onpagehide,' +
//     'Image,Option,Worker,' +
//     // https://developer.mozilla.org/en/Gecko_DOM_Reference
//     'Event,Range,File,FileReader,Blob,BlobBuilder,' +
//     'Attr,CDATASection,CharacterData,Comment,console,DocumentFragment,DocumentType,DomConfiguration,DOMError,DOMErrorHandler,DOMException,DOMImplementation,DOMImplementationList,DOMImplementationRegistry,DOMImplementationSource,DOMLocator,DOMObject,DOMString,DOMStringList,DOMTimeStamp,DOMUserData,Entity,EntityReference,MediaQueryList,MediaQueryListListener,NameList,NamedNodeMap,Node,NodeFilter,NodeIterator,NodeList,Notation,Plugin,PluginArray,ProcessingInstruction,SharedWorker,Text,TimeRanges,Treewalker,TypeInfo,UserDataHandler,Worker,WorkerGlobalScope,' +
//     'HTMLDocument,HTMLElement,HTMLAnchorElement,HTMLAppletElement,HTMLAudioElement,HTMLAreaElement,HTMLBaseElement,HTMLBaseFontElement,HTMLBodyElement,HTMLBRElement,HTMLButtonElement,HTMLCanvasElement,HTMLDirectoryElement,HTMLDivElement,HTMLDListElement,HTMLEmbedElement,HTMLFieldSetElement,HTMLFontElement,HTMLFormElement,HTMLFrameElement,HTMLFrameSetElement,HTMLHeadElement,HTMLHeadingElement,HTMLHtmlElement,HTMLHRElement,HTMLIFrameElement,HTMLImageElement,HTMLInputElement,HTMLKeygenElement,HTMLLabelElement,HTMLLIElement,HTMLLinkElement,HTMLMapElement,HTMLMenuElement,HTMLMetaElement,HTMLModElement,HTMLObjectElement,HTMLOListElement,HTMLOptGroupElement,HTMLOptionElement,HTMLOutputElement,HTMLParagraphElement,HTMLParamElement,HTMLPreElement,HTMLQuoteElement,HTMLScriptElement,HTMLSelectElement,HTMLSourceElement,HTMLSpanElement,HTMLStyleElement,HTMLTableElement,HTMLTableCaptionElement,HTMLTableCellElement,HTMLTableDataCellElement,HTMLTableHeaderCellElement,HTMLTableColElement,HTMLTableRowElement,HTMLTableSectionElement,HTMLTextAreaElement,HTMLTimeElement,HTMLTitleElement,HTMLTrackElement,HTMLUListElement,HTMLUnknownElement,HTMLVideoElement,' +
//     'HTMLCanvasElement,CanvasRenderingContext2D,CanvasGradient,CanvasPattern,TextMetrics,ImageData,CanvasPixelArray,HTMLAudioElement,HTMLVideoElement,NotifyAudioAvailableEvent,HTMLCollection,HTMLAllCollection,HTMLFormControlsCollection,HTMLOptionsCollection,HTMLPropertiesCollection,DOMTokenList,DOMSettableTokenList,DOMStringMap,RadioNodeList,' +
//     'SVGDocument,SVGElement,SVGAElement,SVGAltGlyphElement,SVGAltGlyphDefElement,SVGAltGlyphItemElement,SVGAnimationElement,SVGAnimateElement,SVGAnimateColorElement,SVGAnimateMotionElement,SVGAnimateTransformElement,SVGSetElement,SVGCircleElement,SVGClipPathElement,SVGColorProfileElement,SVGCursorElement,SVGDefsElement,SVGDescElement,SVGEllipseElement,SVGFilterElement,SVGFilterPrimitiveStandardAttributes,SVGFEBlendElement,SVGFEColorMatrixElement,SVGFEComponentTransferElement,SVGFECompositeElement,SVGFEConvolveMatrixElement,SVGFEDiffuseLightingElement,SVGFEDisplacementMapElement,SVGFEDistantLightElement,SVGFEFloodElement,SVGFEGaussianBlurElement,SVGFEImageElement,SVGFEMergeElement,SVGFEMergeNodeElement,SVGFEMorphologyElement,SVGFEOffsetElement,SVGFEPointLightElement,SVGFESpecularLightingElement,SVGFESpotLightElement,SVGFETileElement,SVGFETurbulenceElement,SVGComponentTransferFunctionElement,SVGFEFuncRElement,SVGFEFuncGElement,SVGFEFuncBElement,SVGFEFuncAElement,SVGFontElement,SVGFontFaceElement,SVGFontFaceFormatElement,SVGFontFaceNameElement,SVGFontFaceSrcElement,SVGFontFaceUriElement,SVGForeignObjectElement,SVGGElement,SVGGlyphElement,SVGGlyphRefElement,SVGGradientElement,SVGLinearGradientElement,SVGRadialGradientElement,SVGHKernElement,SVGImageElement,SVGLineElement,SVGMarkerElement,SVGMaskElement,SVGMetadataElement,SVGMissingGlyphElement,SVGMPathElement,SVGPathElement,SVGPatternElement,SVGPolylineElement,SVGPolygonElement,SVGRectElement,SVGScriptElement,SVGStopElement,SVGStyleElement,SVGSVGElement,SVGSwitchElement,SVGSymbolElement,SVGTextElement,SVGTextPathElement,SVGTitleElement,SVGTRefElement,SVGTSpanElement,SVGUseElement,SVGViewElement,SVGVKernElement,' +
//     'SVGAngle,SVGColor,SVGICCColor,SVGElementInstance,SVGElementInstanceList,SVGLength,SVGLengthList,SVGMatrix,SVGNumber,SVGNumberList,SVGPaint,SVGPoint,SVGPointList,SVGPreserveAspectRatio,SVGRect,SVGStringList,SVGTransform,SVGTransformList,' +
//     'SVGAnimatedAngle,SVGAnimatedBoolean,SVGAnimatedEnumeration,SVGAnimatedInteger,SVGAnimatedLength,SVGAnimatedLengthList,SVGAnimatedNumber,SVGAnimatedNumberList,SVGAnimatedPreserveAspectRatio,SVGAnimatedRect,SVGAnimatedString,SVGAnimatedTransformList,' +
//     'SVGPathSegList,SVGPathSeg,SVGPathSegArcAbs,SVGPathSegArcRel,SVGPathSegClosePath,SVGPathSegCurvetoCubicAbs,SVGPathSegCurvetoCubicRel,SVGPathSegCurvetoCubicSmoothAbs,SVGPathSegCurvetoCubicSmoothRel,SVGPathSegCurvetoQuadraticAbs,SVGPathSegCurvetoQuadraticRel,SVGPathSegCurvetoQuadraticSmoothAbs,SVGPathSegCurvetoQuadraticSmoothRel,SVGPathSegLinetoAbs,SVGPathSegLinetoHorizontalAbs,SVGPathSegLinetoHorizontalRel,SVGPathSegLinetoRel,SVGPathSegLinetoVerticalAbs,SVGPathSegLinetoVerticalRel,SVGPathSegMovetoAbs,SVGPathSegMovetoRel,ElementTimeControl,TimeEvent,SVGAnimatedPathData,' +
//     'SVGAnimatedPoints,SVGColorProfileRule,SVGCSSRule,SVGExternalResourcesRequired,SVGFitToViewBox,SVGLangSpace,SVGLocatable,SVGRenderingIntent,SVGStylable,SVGTests,SVGTextContentElement,SVGTextPositioningElement,SVGTransformable,SVGUnitTypes,SVGURIReference,SVGViewSpec,SVGZoomAndPan');

/**
 * Order of operation ENUMs.
 * https://developer.mozilla.org/en/JavaScript/Reference/Operators/Operator_Precedence
 */
Blockly.JavaScript.ORDER_ATOMIC = 0;         // 0 "" ...
Blockly.JavaScript.ORDER_MEMBER = 1;         // . []
Blockly.JavaScript.ORDER_NEW = 1;            // new
Blockly.JavaScript.ORDER_FUNCTION_CALL = 2;  // ()
Blockly.JavaScript.ORDER_INCREMENT = 3;      // ++
Blockly.JavaScript.ORDER_DECREMENT = 3;      // --
Blockly.JavaScript.ORDER_LOGICAL_NOT = 4;    // !
Blockly.JavaScript.ORDER_BITWISE_NOT = 4;    // ~
Blockly.JavaScript.ORDER_UNARY_PLUS = 4;     // +
Blockly.JavaScript.ORDER_UNARY_NEGATION = 4; // -
Blockly.JavaScript.ORDER_TYPEOF = 4;         // typeof
Blockly.JavaScript.ORDER_VOID = 4;           // void
Blockly.JavaScript.ORDER_DELETE = 4;         // delete
Blockly.JavaScript.ORDER_MULTIPLICATION = 5; // *
Blockly.JavaScript.ORDER_DIVISION = 5;       // /
Blockly.JavaScript.ORDER_MODULUS = 5;        // %
Blockly.JavaScript.ORDER_ADDITION = 6;       // +
Blockly.JavaScript.ORDER_SUBTRACTION = 6;    // -
Blockly.JavaScript.ORDER_BITWISE_SHIFT = 7;  // << >> >>>
Blockly.JavaScript.ORDER_RELATIONAL = 8;     // < <= > >=
Blockly.JavaScript.ORDER_IN = 8;             // in
Blockly.JavaScript.ORDER_INSTANCEOF = 8;     // instanceof
Blockly.JavaScript.ORDER_EQUALITY = 9;       // == != === !==
Blockly.JavaScript.ORDER_BITWISE_AND = 10;   // &
Blockly.JavaScript.ORDER_BITWISE_XOR = 11;   // ^
Blockly.JavaScript.ORDER_BITWISE_OR = 12;    // |
Blockly.JavaScript.ORDER_LOGICAL_AND = 13;   // &&
Blockly.JavaScript.ORDER_LOGICAL_OR = 14;    // ||
Blockly.JavaScript.ORDER_CONDITIONAL = 15;   // ?:
Blockly.JavaScript.ORDER_ASSIGNMENT = 16;    // = += -= *= /= %= <<= >>= ...
Blockly.JavaScript.ORDER_COMMA = 17;         // ,
Blockly.JavaScript.ORDER_ANONYMOUS_FUNCTION = 79; // local variable declaration expression
Blockly.JavaScript.ORDER_NONE = 99;          // (...)

/**
 * Arbitrary code to inject into locations that risk causing infinite loops.
 * Any instances of '%1' will be replaced by the block ID that failed.
 * E.g. '  checkTimeout(%1);\n'
 * @type ?string
 */
Blockly.JavaScript.INFINITE_LOOP_TRAP = null;

/**
 * Initialise the database of variable names.
 */
Blockly.JavaScript.init = function() {
  // Create a dictionary of definitions to be printed before the code.
  Blockly.JavaScript.definitions_ = {};

  if (Blockly.Variables) {
    if (!Blockly.JavaScript.variableDB_) {
      Blockly.JavaScript.variableDB_ =
          new Blockly.Names(Blockly.JavaScript.RESERVED_WORDS_);
    } else {
      Blockly.JavaScript.variableDB_.reset();
    }

    var defvars = [];
    var variables = Blockly.Variables.allVariables();
    for (var x = 0; x < variables.length; x++) {
      defvars[x] = 'var ' +
          Blockly.JavaScript.variableDB_.getName(variables[x],
          Blockly.Variables.NAME_TYPE) + ';';
    }
    Blockly.JavaScript.definitions_['variables'] = defvars.join('\n');
  }
};

/**
 * Prepend the generated code with the variable definitions.
 * @param {string} code Generated code.
 * @return {string} Completed code.
 */
Blockly.JavaScript.finish = function(code) {
  // Convert the definitions dictionary into a list.
  var definitions = [];
  for (var name in Blockly.JavaScript.definitions_) {
    definitions.push(Blockly.JavaScript.definitions_[name]);
  }
  return definitions.join('\n\n') + '\n\n\n' + code;
};

/**
 * Naked values are top-level blocks with outputs that aren't plugged into
 * anything.  A trailing semicolon is needed to make this legal.
 * @param {string} line Line of generated code.
 * @return {string} Legal line of code.
 */
Blockly.JavaScript.scrubNakedValue = function(line) {
  return line + ';\n';
};

/**
 * Encode a string as a properly escaped JavaScript string, complete with
 * quotes.
 * @param {string} string Text to encode.
 * @return {string} JavaScript string.
 * @private
 */
Blockly.JavaScript.quote_ = function(string) {
  // TODO: This is a quick hack.  Replace with goog.string.quote
  string = string.replace(/\\/g, '\\\\')
                 .replace(/\n/g, '\\\n')
                 .replace(/'/g, '\\\'');
  return '\'' + string + '\'';
};

/**
 * Common tasks for generating JavaScript from blocks.
 * Handles comments for the specified block and any connected value blocks.
 * Calls any statements following this block.
 * @param {!Blockly.Block} block The current block.
 * @param {string} code The JavaScript code created for this block.
 * @return {string} JavaScript code with comments and subsequent blocks added.
 * @this {Blockly.CodeGenerator}
 * @private
 */
Blockly.JavaScript.scrub_ = function(block, code) {
  if (code === null) {
    // Block has handled code generation itself.
    return '';
  }
  var commentCode = '';
  // Only collect comments for blocks that aren't inline.
  if (!block.outputConnection || !block.outputConnection.targetConnection) {
    // Collect comment for this block.
    var comment = block.getCommentText();
    if (comment) {
      commentCode += Blockly.JavaScript.prefixLines(comment, '// ') + '\n';
    }
    // Collect comments for all value arguments.
    // Don't collect comments for nested statements.
    for (var x = 0; x < block.inputList.length; x++) {
      if (block.inputList[x].type == Blockly.INPUT_VALUE) {
        var childBlock = block.inputList[x].connection.targetBlock();
        if (childBlock) {
          var comment = Blockly.JavaScript.allNestedComments(childBlock);
          if (comment) {
            commentCode += Blockly.JavaScript.prefixLines(comment, '// ');
          }
        }
      }
    }
  }
  var nextBlock = block.nextConnection && block.nextConnection.targetBlock();
  var nextCode = this.blockToCode(nextBlock);
  return commentCode + code + nextCode;
};