firefox-main/devtools/client/shared/components/tree/ObjectProvider.mjs (file symbol)

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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* eslint no-shadow: ["error", { "allow": ["name"] }] */
import { JSON_NUMBER } from "resource://devtools/client/shared/components/reps/reps/constants.mjs";
const MAX_NUMERICAL_PROPERTIES = 100;
/**
* Implementation of the default data provider. A provider is state less
* object responsible for transformation data (usually a state) to
* a structure that can be directly consumed by the tree-view component.
*/
const ObjectProvider = {
getChildren(object, options = {}) {
const { bucketLargeArrays = false } = options;
const children = [];
if (bucketLargeArrays && object instanceof BucketProperty) {
// Expand a bucket by returning its range of properties
const actualObject = object.object;
const { startIndex, endIndex } = object;
const bucketSize = endIndex - startIndex + 1;
// If this bucket is still too large (>100 elements), create nested buckets
if (bucketSize > MAX_NUMERICAL_PROPERTIES) {
return this.makeBuckets(actualObject, startIndex, endIndex);
}
// Otherwise, return the actual array elements
for (let i = startIndex; i <= endIndex; i++) {
children.push(new ObjectProperty(String(i), actualObject[i]));
}
return children;
}
if (object instanceof ObjectProperty) {
object = object.value;
}
if (!object) {
return [];
}
if (object?.type === JSON_NUMBER) {
return [];
}
if (typeof object == "string") {
return [];
}
// Check if bucketing is enabled and this is an array with many elements
if (
bucketLargeArrays &&
Array.isArray(object) &&
object.length > MAX_NUMERICAL_PROPERTIES
) {
return this.makeBuckets(object);
}
for (const prop in object) {
try {
children.push(new ObjectProperty(prop, object[prop]));
} catch (e) {
console.error(e);
}
}
return children;
},
makeBuckets(array, startIndex = 0, endIndex = array.length - 1) {
const numProperties = endIndex - startIndex + 1;
// We want to have at most a hundred slices.
// This matches the bucketing algorithm in
// devtools/client/shared/components/object-inspector/utils/node.js
const bucketSize =
10 ** Math.max(2, Math.ceil(Math.log10(numProperties)) - 2);
const numBuckets = Math.ceil(numProperties / bucketSize);
const buckets = [];
for (let i = 1; i <= numBuckets; i++) {
const minKey = (i - 1) * bucketSize;
const maxKey = Math.min(i * bucketSize - 1, numProperties - 1);
const minIndex = startIndex + minKey;
const maxIndex = startIndex + maxKey;
const bucketName = `[${minIndex}…${maxIndex}]`;
buckets.push(new BucketProperty(bucketName, array, minIndex, maxIndex));
}
return buckets;
},
hasChildren(object) {
if (object instanceof BucketProperty) {
// Buckets always have children (the range of properties they represent)
return true;
}
if (object instanceof ObjectProperty) {
object = object.value;
}
if (!object) {
return false;
}
if (object.type === JSON_NUMBER) {
return false;
}
if (typeof object == "string") {
return false;
}
if (typeof object !== "object") {
return false;
}
return !!Object.keys(object).length;
},
getLabel(object) {
// Both BucketProperty and ObjectProperty have a .name property
return object instanceof BucketProperty || object instanceof ObjectProperty
? object.name
: null;
},
getValue(object) {
return object instanceof ObjectProperty ? object.value : null;
},
getKey(object) {
// Both BucketProperty and ObjectProperty use .name as their key
return object instanceof BucketProperty || object instanceof ObjectProperty
? object.name
: null;
},
getType(object) {
if (object instanceof BucketProperty) {
return "bucket";
}
return object instanceof ObjectProperty
? typeof object.value
: typeof object;
},
};
function ObjectProperty(name, value) {
this.name = name;
this.value = value;
}
function BucketProperty(name, object, startIndex, endIndex) {
this.name = name;
this.object = object;
this.startIndex = startIndex;
this.endIndex = endIndex;
}
// Exports from this module
export { BucketProperty, ObjectProperty, ObjectProvider };