de36b2aaba
Note that Prettier, purposely, has only limited [configuration options](https://prettier.io/docs/en/options.html). The configuration file is based on [the one in `mozilla central`](https://searchfox.org/mozilla-central/source/.prettierrc) with just a few additions (to avoid future breakage if the defaults ever changes). Prettier is being used for a couple of reasons: - To be consistent with `mozilla-central`, where Prettier is already in use across the tree. - To ensure a *consistent* coding style everywhere, which is automatically enforced during linting (since Prettier is used as an ESLint plugin). This thus ends "all" formatting disussions once and for all, removing the need for review comments on most stylistic matters. Many ESLint options are now redundant, and I've tried my best to remove all the now unnecessary options (but I may have missed some). Note also that since Prettier considers the `printWidth` option as a guide, rather than a hard rule, this patch resorts to a small hack in the ESLint config to ensure that *comments* won't become too long. *Please note:* This patch is generated automatically, by appending the `--fix` argument to the ESLint call used in the `gulp lint` task. It will thus require some additional clean-up, which will be done in a *separate* commit. (On a more personal note, I'll readily admit that some of the changes Prettier makes are *extremely* ugly. However, in the name of consistency we'll probably have to live with that.)
99 lines
3.2 KiB
JavaScript
99 lines
3.2 KiB
JavaScript
/* Copyright 2017 Mozilla Foundation
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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var Canvas = require("canvas");
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var assert = require("assert").strict;
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var fs = require("fs");
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function NodeCanvasFactory() {}
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NodeCanvasFactory.prototype = {
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create: function NodeCanvasFactory_create(width, height) {
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assert(width > 0 && height > 0, "Invalid canvas size");
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var canvas = Canvas.createCanvas(width, height);
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var context = canvas.getContext("2d");
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return {
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canvas: canvas,
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context: context,
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};
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},
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reset: function NodeCanvasFactory_reset(canvasAndContext, width, height) {
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assert(canvasAndContext.canvas, "Canvas is not specified");
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assert(width > 0 && height > 0, "Invalid canvas size");
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canvasAndContext.canvas.width = width;
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canvasAndContext.canvas.height = height;
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},
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destroy: function NodeCanvasFactory_destroy(canvasAndContext) {
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assert(canvasAndContext.canvas, "Canvas is not specified");
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// Zeroing the width and height cause Firefox to release graphics
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// resources immediately, which can greatly reduce memory consumption.
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canvasAndContext.canvas.width = 0;
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canvasAndContext.canvas.height = 0;
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canvasAndContext.canvas = null;
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canvasAndContext.context = null;
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},
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};
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var pdfjsLib = require("pdfjs-dist");
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// Relative path of the PDF file.
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var pdfURL = "../../../web/compressed.tracemonkey-pldi-09.pdf";
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// Read the PDF file into a typed array so PDF.js can load it.
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var rawData = new Uint8Array(fs.readFileSync(pdfURL));
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// Load the PDF file.
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var loadingTask = pdfjsLib.getDocument(rawData);
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loadingTask.promise
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.then(function(pdfDocument) {
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console.log("# PDF document loaded.");
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// Get the first page.
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pdfDocument.getPage(1).then(function(page) {
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// Render the page on a Node canvas with 100% scale.
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var viewport = page.getViewport({ scale: 1.0 });
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var canvasFactory = new NodeCanvasFactory();
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var canvasAndContext = canvasFactory.create(
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viewport.width,
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viewport.height
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);
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var renderContext = {
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canvasContext: canvasAndContext.context,
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viewport: viewport,
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canvasFactory: canvasFactory,
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};
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var renderTask = page.render(renderContext);
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renderTask.promise.then(function() {
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// Convert the canvas to an image buffer.
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var image = canvasAndContext.canvas.toBuffer();
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fs.writeFile("output.png", image, function(error) {
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if (error) {
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console.error("Error: " + error);
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} else {
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console.log(
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"Finished converting first page of PDF file to a PNG image."
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);
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}
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});
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});
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});
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})
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.catch(function(reason) {
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console.log(reason);
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});
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