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mirror of https://github.com/Jermolene/TiddlyWiki5 synced 2024-12-26 10:00:34 +00:00
TiddlyWiki5/core/modules/widgets/transclude.js
Cameron Fischer e932b09016
More robust infinite recursion handling with custom exception (#7882)
* Introduced preliminary idea for infinite recurse exception

* Better handling of infinite recursion

But it could be better still...

* the TransclusionError is a proper error

Moved the magic number to be on the error's class. Not sure if that's
a great idea.

* Fixed minor minor issue that came up in conflict

The minor fix to the jasmine regexp that escaped a '+' somehow
broke some random test.
2024-05-25 10:56:19 +01:00

485 lines
16 KiB
JavaScript
Executable File

/*\
title: $:/core/modules/widgets/transclude.js
type: application/javascript
module-type: widget
Transclude widget
\*/
(function(){
/*jslint node: true, browser: true */
/*global $tw: false */
"use strict";
var Widget = require("$:/core/modules/widgets/widget.js").widget;
var TranscludeWidget = function(parseTreeNode,options) {
this.initialise(parseTreeNode,options);
};
/*
Inherit from the base widget class
*/
TranscludeWidget.prototype = new Widget();
/*
Render this widget into the DOM
*/
TranscludeWidget.prototype.render = function(parent,nextSibling) {
this.parentDomNode = parent;
this.computeAttributes();
this.execute();
try {
this.renderChildren(parent,nextSibling);
} catch(error) {
if(error instanceof $tw.utils.TranscludeRecursionError) {
// We were infinite looping.
// We need to try and abort as much of the loop as we can, so we will keep "throwing" upward until we find a transclusion that has a different signature.
// Hopefully that will land us just outside where the loop began. That's where we want to issue an error.
// Rendering widgets beneath this point may result in a freezing browser if they explode exponentially.
var transcludeSignature = this.getVariable("transclusion");
if(this.getAncestorCount() > $tw.utils.TranscludeRecursionError.MAX_WIDGET_TREE_DEPTH - 50) {
// For the first fifty transcludes we climb up, we simply collect signatures.
// We're assuming that those first 50 will likely include all transcludes involved in the loop.
error.signatures[transcludeSignature] = true;
} else if(!error.signatures[transcludeSignature]) {
// Now that we're past the first 50, let's look for the first signature that wasn't in the loop. That'll be where we print the error and resume rendering.
this.children = [this.makeChildWidget({type: "error", attributes: {
"$message": {type: "string", value: $tw.language.getString("Error/RecursiveTransclusion")}
}})];
this.renderChildren(parent,nextSibling);
return;
}
}
throw error;
}
};
/*
Compute the internal state of the widget
*/
TranscludeWidget.prototype.execute = function() {
// Get our attributes, string parameters, and slot values into properties of the widget object
this.collectAttributes();
this.collectStringParameters();
this.collectSlotFillParameters();
// Determine whether we're being used in inline or block mode
var parseAsInline = !this.parseTreeNode.isBlock;
if(this.transcludeMode === "inline") {
parseAsInline = true;
} else if(this.transcludeMode === "block") {
parseAsInline = false;
}
// Set 'thisTiddler'
this.setVariable("thisTiddler",this.transcludeTitle);
var parseTreeNodes, target;
// Process the transclusion according to the output type
switch(this.transcludeOutput || "text/html") {
case "text/html":
// Return the parse tree nodes of the target
target = this.parseTransclusionTarget(parseAsInline);
this.parseAsInline = target.parseAsInline;
parseTreeNodes = target.parseTreeNodes;
break;
case "text/raw":
// Just return the raw text
target = this.getTransclusionTarget();
parseTreeNodes = [{type: "text", text: target.text}];
break;
default:
// "text/plain" is the plain text result of wikifying the text
target = this.parseTransclusionTarget(parseAsInline);
var widgetNode = this.wiki.makeWidget(target.parser,{
parentWidget: this,
document: $tw.fakeDocument
});
var container = $tw.fakeDocument.createElement("div");
widgetNode.render(container,null);
parseTreeNodes = [{type: "text", text: container.textContent}];
break;
}
this.sourceText = target.text;
this.parserType = target.type;
// Set the legacy transclusion context variables only if we're not transcluding a variable
if(!this.transcludeVariable) {
var recursionMarker = this.makeRecursionMarker();
this.setVariable("transclusion",recursionMarker);
}
// Construct the child widgets
this.makeChildWidgets(parseTreeNodes);
};
/*
Collect the attributes we need, in the process determining whether we're being used in legacy mode
*/
TranscludeWidget.prototype.collectAttributes = function() {
var self = this;
// Detect legacy mode
this.legacyMode = true;
$tw.utils.each(this.attributes,function(value,name) {
if(name.charAt(0) === "$") {
self.legacyMode = false;
}
});
// Get the attributes for the appropriate mode
if(this.legacyMode) {
this.transcludeTitle = this.getAttribute("tiddler",this.getVariable("currentTiddler"));
this.transcludeSubTiddler = this.getAttribute("subtiddler");
this.transcludeField = this.getAttribute("field");
this.transcludeIndex = this.getAttribute("index");
this.transcludeMode = this.getAttribute("mode");
this.recursionMarker = this.getAttribute("recursionMarker","yes");
} else {
this.transcludeVariable = this.getAttribute("$variable");
this.transcludeVariableIsFunction = false;
this.transcludeType = this.getAttribute("$type");
this.transcludeOutput = this.getAttribute("$output","text/html");
this.transcludeTitle = this.getAttribute("$tiddler",this.getVariable("currentTiddler"));
this.transcludeSubTiddler = this.getAttribute("$subtiddler");
this.transcludeField = this.getAttribute("$field");
this.transcludeIndex = this.getAttribute("$index");
this.transcludeMode = this.getAttribute("$mode");
this.recursionMarker = this.getAttribute("$recursionMarker","yes");
}
};
/*
Collect string parameters
*/
TranscludeWidget.prototype.collectStringParameters = function() {
var self = this;
this.stringParametersByName = Object.create(null);
if(!this.legacyMode) {
$tw.utils.each(this.attributes,function(value,name) {
if(name.charAt(0) === "$") {
if(name.charAt(1) === "$") {
// Attributes starting $$ represent parameters starting with a single $
name = name.slice(1);
} else {
// Attributes starting with a single $ are reserved for the widget
return;
}
}
self.stringParametersByName[name] = value;
});
}
};
/*
Collect slot value parameters
*/
TranscludeWidget.prototype.collectSlotFillParameters = function() {
var self = this;
this.slotFillParseTrees = Object.create(null);
if(this.legacyMode) {
this.slotFillParseTrees["ts-missing"] = this.parseTreeNode.children;
} else {
this.slotFillParseTrees["ts-raw"] = this.parseTreeNode.children;
var noFillWidgetsFound = true,
searchParseTreeNodes = function(nodes) {
$tw.utils.each(nodes,function(node) {
if(node.type === "fill") {
if(node.attributes["$name"] && node.attributes["$name"].type === "string") {
var slotValueName = node.attributes["$name"].value;
self.slotFillParseTrees[slotValueName] = node.children || [];
}
noFillWidgetsFound = false;
} else {
searchParseTreeNodes(node.children);
}
});
};
searchParseTreeNodes(this.parseTreeNode.children);
if(noFillWidgetsFound) {
this.slotFillParseTrees["ts-missing"] = this.parseTreeNode.children;
}
}
};
/*
Get transcluded details as an object {text:,type:}
*/
TranscludeWidget.prototype.getTransclusionTarget = function() {
var self = this;
var text;
// Return the text and type of the target
if(this.hasAttribute("$variable")) {
if(this.transcludeVariable) {
// Transcluding a variable
var variableInfo = this.getVariableInfo(this.transcludeVariable,{params: this.getOrderedTransclusionParameters()});
this.transcludeVariableIsFunction = variableInfo.srcVariable && variableInfo.srcVariable.isFunctionDefinition;
text = variableInfo.text;
this.transcludeFunctionResult = text;
return {
text: variableInfo.text,
type: this.transcludeType
};
}
} else {
// Transcluding a text reference
var parserInfo = this.wiki.getTextReferenceParserInfo(
this.transcludeTitle,
this.transcludeField,
this.transcludeIndex,
{
subTiddler: this.transcludeSubTiddler,
defaultType: this.transcludeType
});
return {
text: parserInfo.text,
type: parserInfo.type
};
}
};
/*
Get transcluded parse tree nodes as an object {text:,type:,parseTreeNodes:,parseAsInline:}
*/
TranscludeWidget.prototype.parseTransclusionTarget = function(parseAsInline) {
var self = this;
var parser;
// Get the parse tree
if(this.hasAttribute("$variable")) {
if(this.transcludeVariable) {
// Transcluding a variable
var variableInfo = this.getVariableInfo(this.transcludeVariable,{params: this.getOrderedTransclusionParameters()}),
srcVariable = variableInfo && variableInfo.srcVariable;
if(srcVariable && srcVariable.isFunctionDefinition) {
this.transcludeVariableIsFunction = true;
this.transcludeFunctionResult = (variableInfo.resultList ? variableInfo.resultList[0] : variableInfo.text) || "";
}
if(variableInfo.text) {
if(srcVariable && srcVariable.isFunctionDefinition) {
parser = {
tree: [{
type: "text",
text: this.transcludeFunctionResult
}],
source: this.transcludeFunctionResult,
type: "text/vnd.tiddlywiki"
};
if(parseAsInline) {
parser.tree[0] = {
type: "text",
text: this.transcludeFunctionResult
};
} else {
parser.tree[0] = {
type: "element",
tag: "p",
children: [{
type: "text",
text: this.transcludeFunctionResult
}]
}
}
} else {
var cacheKey = (parseAsInline ? "inlineParser" : "blockParser") + (this.transcludeType || "");
if(variableInfo.isCacheable && srcVariable[cacheKey]) {
parser = srcVariable[cacheKey];
} else {
parser = this.wiki.parseText(this.transcludeType,variableInfo.text || "",{parseAsInline: parseAsInline, configTrimWhiteSpace: srcVariable && srcVariable.configTrimWhiteSpace});
if(variableInfo.isCacheable) {
srcVariable[cacheKey] = parser;
}
}
}
if(parser) {
// Add parameters widget for procedures and custom widgets
if(srcVariable && (srcVariable.isProcedureDefinition || srcVariable.isWidgetDefinition)) {
parser = {
tree: [
{
type: "parameters",
children: parser.tree
}
],
source: parser.source,
type: parser.type
}
$tw.utils.each(srcVariable.params,function(param) {
var name = param.name;
// Parameter names starting with dollar must be escaped to double dollars
if(name.charAt(0) === "$") {
name = "$" + name;
}
$tw.utils.addAttributeToParseTreeNode(parser.tree[0],name,param["default"])
});
} else if(srcVariable && !srcVariable.isFunctionDefinition) {
// For macros and ordinary variables, wrap the parse tree in a vars widget assigning the parameters to variables named "__paramname__"
parser = {
tree: [
{
type: "vars",
children: parser.tree
}
],
source: parser.source,
type: parser.type
}
$tw.utils.each(variableInfo.params,function(param) {
$tw.utils.addAttributeToParseTreeNode(parser.tree[0],"__" + param.name + "__",param.value)
});
}
}
}
}
} else {
// Transcluding a text reference
parser = this.wiki.parseTextReference(
this.transcludeTitle,
this.transcludeField,
this.transcludeIndex,
{
parseAsInline: parseAsInline,
subTiddler: this.transcludeSubTiddler,
defaultType: this.transcludeType
});
}
// Return the parse tree
return {
parser: parser,
parseTreeNodes: parser ? parser.tree : (this.slotFillParseTrees["ts-missing"] || []),
parseAsInline: parseAsInline,
text: parser && parser.source,
type: parser && parser.type
};
};
/*
Fetch all the string parameters as an ordered array of {name:, value:} where the name is optional
*/
TranscludeWidget.prototype.getOrderedTransclusionParameters = function() {
var result = [];
// Collect the parameters
for(var name in this.stringParametersByName) {
var value = this.stringParametersByName[name];
result.push({name: name, value: value});
}
// Sort numerical parameter names first
result.sort(function(a,b) {
var aIsNumeric = !isNaN(a.name),
bIsNumeric = !isNaN(b.name);
if(aIsNumeric && bIsNumeric) {
return a.name - b.name;
} else if(aIsNumeric) {
return -1;
} else if(bIsNumeric) {
return 1;
} else {
return a.name === b.name ? 0 : (a.name < b.name ? -1 : 1);
}
});
// Remove names from numerical parameters
$tw.utils.each(result,function(param,index) {
if(!isNaN(param.name)) {
delete param.name;
}
});
return result;
};
/*
Fetch the value of a parameter
*/
TranscludeWidget.prototype.getTransclusionParameter = function(name,index,defaultValue) {
if(name in this.stringParametersByName) {
return this.stringParametersByName[name];
} else {
var name = "" + index;
if(name in this.stringParametersByName) {
return this.stringParametersByName[name];
}
}
return defaultValue;
};
/*
Get one of the special parameters to be provided by the parameters widget
*/
TranscludeWidget.prototype.getTransclusionMetaParameters = function() {
var self = this;
return {
"parseMode": function() {
return self.parseAsInline ? "inline" : "block";
},
"parseTreeNodes": function() {
return JSON.stringify(self.parseTreeNode.children || []);
},
"slotFillParseTreeNodes": function() {
return JSON.stringify(self.slotFillParseTrees);
},
"params": function() {
return JSON.stringify(self.stringParametersByName);
}
};
};
/*
Fetch the value of a slot
*/
TranscludeWidget.prototype.getTransclusionSlotFill = function(name,defaultParseTreeNodes) {
if(name && this.slotFillParseTrees[name] && this.slotFillParseTrees[name].length > 0) {
return this.slotFillParseTrees[name];
} else {
return defaultParseTreeNodes || [];
}
};
/*
Return whether this transclusion should be visible to the slot widget
*/
TranscludeWidget.prototype.hasVisibleSlots = function() {
return this.getAttribute("$fillignore","no") === "no";
}
/*
Compose a string comprising the title, field and/or index to identify this transclusion for recursion detection
*/
TranscludeWidget.prototype.makeRecursionMarker = function() {
var output = [];
output.push("{");
output.push(this.getVariable("currentTiddler",{defaultValue: ""}));
output.push("|");
output.push(this.transcludeTitle || "");
output.push("|");
output.push(this.transcludeField || "");
output.push("|");
output.push(this.transcludeIndex || "");
output.push("|");
output.push(this.transcludeSubTiddler || "");
output.push("}");
return output.join("");
};
TranscludeWidget.prototype.parserNeedsRefresh = function() {
// Doesn't need to consider transcluded variables because a parent variable can't change once a widget has been created
var parserInfo = this.wiki.getTextReferenceParserInfo(this.transcludeTitle,this.transcludeField,this.transcludeIndex,{subTiddler:this.transcludeSubTiddler});
return (this.sourceText === undefined || parserInfo.sourceText !== this.sourceText || parserInfo.parserType !== this.parserType)
};
TranscludeWidget.prototype.functionNeedsRefresh = function() {
var oldResult = this.transcludeFunctionResult;
var variableInfo = this.getVariableInfo(this.transcludeVariable,{params: this.getOrderedTransclusionParameters()});
var newResult = (variableInfo.resultList ? variableInfo.resultList[0] : variableInfo.text) || "";
return oldResult !== newResult;
}
/*
Selectively refreshes the widget if needed. Returns true if the widget or any of its children needed re-rendering
*/
TranscludeWidget.prototype.refresh = function(changedTiddlers) {
var changedAttributes = this.computeAttributes();
if(($tw.utils.count(changedAttributes) > 0) || (this.transcludeVariableIsFunction && this.functionNeedsRefresh()) || (!this.transcludeVariable && changedTiddlers[this.transcludeTitle] && this.parserNeedsRefresh())) {
this.refreshSelf();
return true;
} else {
return this.refreshChildren(changedTiddlers);
}
};
exports.transclude = TranscludeWidget;
})();