challenge-algorithms-v2.0-u.../node_modules/istanbul-lib-report/lib/tree.js

138 lines
3.7 KiB
JavaScript

/*
Copyright 2012-2015, Yahoo Inc.
Copyrights licensed under the New BSD License. See the accompanying LICENSE file for terms.
*/
'use strict';
/**
* An object with methods that are called during the traversal of the coverage tree.
* A visitor has the following methods that are called during tree traversal.
*
* * `onStart(root, state)` - called before traversal begins
* * `onSummary(node, state)` - called for every summary node
* * `onDetail(node, state)` - called for every detail node
* * `onSummaryEnd(node, state)` - called after all children have been visited for
* a summary node.
* * `onEnd(root, state)` - called after traversal ends
*
* @param delegate - a partial visitor that only implements the methods of interest
* The visitor object supplies the missing methods as noops. For example, reports
* that only need the final coverage summary need implement `onStart` and nothing
* else. Reports that use only detailed coverage information need implement `onDetail`
* and nothing else.
* @constructor
*/
class Visitor {
constructor(delegate) {
this.delegate = delegate;
}
}
['Start', 'End', 'Summary', 'SummaryEnd', 'Detail']
.map(k => `on${k}`)
.forEach(fn => {
Object.defineProperty(Visitor.prototype, fn, {
writable: true,
value(node, state) {
if (typeof this.delegate[fn] === 'function') {
this.delegate[fn](node, state);
}
}
});
});
class CompositeVisitor extends Visitor {
constructor(visitors) {
super();
if (!Array.isArray(visitors)) {
visitors = [visitors];
}
this.visitors = visitors.map(v => {
if (v instanceof Visitor) {
return v;
}
return new Visitor(v);
});
}
}
['Start', 'Summary', 'SummaryEnd', 'Detail', 'End']
.map(k => `on${k}`)
.forEach(fn => {
Object.defineProperty(CompositeVisitor.prototype, fn, {
value(node, state) {
this.visitors.forEach(v => {
v[fn](node, state);
});
}
});
});
class BaseNode {
isRoot() {
return !this.getParent();
}
/**
* visit all nodes depth-first from this node down. Note that `onStart`
* and `onEnd` are never called on the visitor even if the current
* node is the root of the tree.
* @param visitor a full visitor that is called during tree traversal
* @param state optional state that is passed around
*/
visit(visitor, state) {
if (this.isSummary()) {
visitor.onSummary(this, state);
} else {
visitor.onDetail(this, state);
}
this.getChildren().forEach(child => {
child.visit(visitor, state);
});
if (this.isSummary()) {
visitor.onSummaryEnd(this, state);
}
}
}
/**
* abstract base class for a coverage tree.
* @constructor
*/
class BaseTree {
constructor(root) {
this.root = root;
}
/**
* returns the root node of the tree
*/
getRoot() {
return this.root;
}
/**
* visits the tree depth-first with the supplied partial visitor
* @param visitor - a potentially partial visitor
* @param state - the state to be passed around during tree traversal
*/
visit(visitor, state) {
if (!(visitor instanceof Visitor)) {
visitor = new Visitor(visitor);
}
visitor.onStart(this.getRoot(), state);
this.getRoot().visit(visitor, state);
visitor.onEnd(this.getRoot(), state);
}
}
module.exports = {
BaseTree,
BaseNode,
Visitor,
CompositeVisitor
};