This is *similar* to the existing linting for JavaScript files, but covers CSS files instead.
While there's a lot of rules that could potentially be used, the main advantage of using Stylelint is that it has Prettier integration which means that we can automatically enforce a *consistent* style for our CSS files as well.
As a proof of concept, this patch is purposely limited to:
- Adding a simple rule, here `block-no-empty` is chosen; see https://stylelint.io/user-guide/rules/block-no-empty
- Adding Prettier integration, to unify the style of our CSS files.
Please find additional information at https://stylelint.io/
Note that this will increase the run-time of `gulp dist` and `gulp dist-install`, but that's unavoidable given that there's now additional building happening.
While this will obviously increase the size of the output of `gulp minified`/`gulp minified-es5` *slightly*, the resulting files are still a lot smaller than the non-minified builds.
See https://github.com/terser/terser#minify-options for information about various Terser options.
- Fix the `gulp types` task to run on Windows. Currently this fails, and the solution was to "borrow" the same formatting as used in the `gulp jsdoc` task.
- Place the TypeScript definitions in their own `types` directory, when building `pdfjs-dist`. These should *not* be cluttering the main `build` directory, especially since the generated TypeScript definitions consists of *multiple folders*. (Only if the TypeScript definitions would be concatenated into *a single file*, would placing them directly in `pdfjs-dist/build` be acceptable.)
This commit:
- moves the preparation work to a new `typestest-pre` target similar to
how the other targets work;
- moves the `TYPESTEST_DIR` definition to the top of the file like we
did for all other directory variables;
- renames the `TYPES_BUILD_DIR` variable to `TYPES_DIR` since it's
shorter and the naming scheme then corresponds to the other directory
variables;
- switches to `const`/template strings in the types targets where needed;
- converts the `if (err !== null)` check to `if (err)` similar to other
targets.
This PR adds typescript definitions from the JSDoc already present.
It adds a new gulp-target 'types' that calls 'tsc', the typescript
compiler, to create the definitions.
To use the definitions, users can simply do the following:
```
import {getDocument, GlobalWorkerOptions} from "pdfjs-dist";
import pdfjsWorker from "pdfjs-dist/build/pdf.worker.entry";
GlobalWorkerOptions.workerSrc = pdfjsWorker;
const pdf = await getDocument("file:///some.pdf").promise;
```
Co-authored-by: @oBusk
Co-authored-by: @tamuratak
This moves, and slightly simplifies, code that's currently residing in the unit-test utils into the actual library, such that it's bundled with `GENERIC`-builds and used in e.g. the API-code.
As an added bonus, this also brings out-of-the-box support for CMaps in e.g. the Node.js examples.
For now we need to use a Babel-plugin, since Webpack 4.x doesn't seem to support it yet. (Most likely we'll have to update to Webpack 5, once that becomes available, in order for this to be directly supported. This is thus also blocked on removing the `webpack-stream` package.)
While the `??` operator will thus always be transpiled by Babel, even in modern builds, simply supporting it for development purposes seems like a step in the right direction.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing_operator
With the changes made in the previous patch, the `web/app_options.js` file no longer depends on anything *except* files residing in the `web/` folder. Hence the `gulp default_preferences` task can now be further simplified and thus becomes even faster than before; see also PR 11724.
By re-factoring the existing gulp tasks, most of the code can be re-used for both the existing `gulp minified` as well as the new `gulp minified-es5` task.
All of the other *similar* helper functions only target one file per function, and there's no particular reason for this one to be different.
This patch will simplify future changes, e.g. experimenting with using `gulp watch` instead of SystemJS for the development viewer.
Not only is there no code depending on it now, the actual task itself doesn't even make sense as-is. Note that it uses the default `DEFINES` configuration *unaltered*, which is neither useful nor correct since the resulting build thus won't make sense without an actual built target set.
To save time or resources during development it can be useful to run
tests only in Firefox. Previously this could be done by editing the
browser manifest file, but since that file is no longer used for
Puppeteer, this command line flag replaces it. For example, executing
`gulp unittest --noChrome` will only run the unit tests in Firefox.
This commit replaces our own infrastructure for handling browsers during
tests with Puppeteer. Using our own infrastructure for this had a few
downsides:
- It has proven to not always be reliable, especially when closing the
browser, causing failures on the bots because browsers were still
running even though they should have been stopped. Puppeteer should do
a better job with this because it uses the browser's test built-in
instrumentation tools for this (the devtools protocol) which our code
didn't. This also means that we don't have to pass
parameters/preferences to tweak browser behavior anymore.
- It requires the browsers under test to be installed on the system,
whereas Puppeteer downloads the browsers before the test. This means
that setup is much easier (no more manual installations and browser
manifest files) as well as testing with different browser versions
(since they can be provisioned on demand). Moreover, this ensures that
contributors always run the tests in both Firefox and Chrome,
regardless of which browsers they have installed locally.
- It's all code we have to maintain, so Puppeteer abstracts away how the
browsers start/stop for us so we don't have to keep that code.
By default, Puppeteer only installs one browser during installation,
hence the need for a post-install script to install the second browser.
This requires `cross-env` to make passing the environment variable work
on both Linux and Windows.
*Please note:* These changes were done automatically, using the `gulp lint --fix` command.
This rule is already enabled in mozilla-central, see https://searchfox.org/mozilla-central/rev/567b68b8ff4b6d607ba34a6f1926873d21a7b4d7/tools/lint/eslint/eslint-plugin-mozilla/lib/configs/recommended.js#103-104
The main advantage, besides improved consistency, of this rule is that it reduces the size of the code (by 3 bytes for each case). In the PDF.js code-base there's close to 8000 instances being fixed by the `dot-notation` ESLint rule, which end up reducing the size of even the *built* files significantly; the total size of the `gulp mozcentral` build target changes from `3 247 456` to `3 224 278` bytes, which is a *reduction* of `23 178` bytes (or ~0.7%) for a completely mechanical change.
A large number of these changes affect the (large) lookup tables used on the worker-thread, but given that they are still initialized lazily I don't *think* that the new formatting this patch introduces should undo any of the improvements from PR 6915.
Please find additional details about the ESLint rule at https://eslint.org/docs/rules/dot-notation
Please note that these changes were done automatically, using `gulp lint --fix`.
Given that the major version number was increased, there's a fair number of (primarily whitespace) changes; please see https://prettier.io/blog/2020/03/21/2.0.0.html
In order to reduce the size of these changes somewhat, this patch maintains the old "arrowParens" style for now (once mozilla-central updates Prettier we can simply choose the same formatting, assuming it will differ here).
I completely overlooked the fact that we had *one* occurrence of an asynchronous `mkdirp` call in the gulpfile, which thus breaks since the package now uses Promises rather than a callback function; sorry about that!
With two kind of builds now being produced, with/without translation/polyfills, it's unfortunately somewhat easy for users to accidentally pick the wrong one.
In the case where a user would attempt to use a modern build of PDF.js in an older browser, such as e.g. IE11, the failure would be immediate when the code is loaded (given the use of unsupported ECMAScript features).
However in some browsers/environments, in particular Node.js, a modern PDF.js build may load correctly and thus *appear* to function, only to fail for e.g. certain API calls. To hopefully lessen the support burden, and to try and improve things overall, this patch adds checks to ensure that a modern build of PDF.js cannot be used in browsers/environments which lack native support for critical functionality (such as e.g. `ReadableStream`). Hence we'll fail early, with an error message telling users to pick an ES5-compatible build instead.
To ensure that we actually test things better especially w.r.t. usage of the PDF.js library in Node.js environments, the `gulp npm-test` task as used by Node.js/Travis was changed (back) to test an ES5-compatible build.
(Since the bots still test the code as-is, without transpilation/polyfills, this shouldn't really be a problem as far as I can tell.)
As part of these changes there's now both `gulp lib` and `gulp lib-es5` build targets, similar to e.g. the generic builds, which thanks to some re-factoring only required adding a small amount of code.
*Please note:* While it's probably too early to tell if this will be a widespread issue, it's possible that this is the sort of patch that *may* warrant being `git cherry-pick`ed onto the current beta version (v2.4.456).
This rule is *not* currently enabled in mozilla-central, but it appears commented out[1] in the ESLint definition file; see https://searchfox.org/mozilla-central/rev/c80fa7258c935223fe319c5345b58eae85d4c6ae/tools/lint/eslint/eslint-plugin-mozilla/lib/configs/recommended.js#238-239
Unfortunately this rule is, for fairly obvious reasons, impossible to `--fix` automatically (even partially) and each case thus required careful manual analysis.
Hence this ESLint rule is, by some margin, probably the most difficult one that we've enabled thus far. However, using this rule does seem like a good idea in general since allowing variable shadowing could lead to subtle (and difficult to find) bugs or at the very least confusing code.
Please find additional details about the ESLint rule at https://eslint.org/docs/rules/no-shadow
---
[1] Most likely, a very large number of lint errors have prevented this rule from being enabled thus far.
*I've had this patch locally for awhile, but have apparently missed to upstream it.*
This simplifies enabling of new ESLint rules, since most of them support automatic fixing of errors, without having to edit `gulpfile.js` or manually invoke ESLint directly.
With the way that the `default_preferences.json` file is now generated at build time, the `gulp lint` task is now noticeably slower than before. This slowdown has been, and still is, somewhat annoying during the deployment of new ESLint rules.
Hence this patch, which moves the `chromium/preferences_schema.json` validation from `gulp lint` and into a new `gulp lint-chromium` task instead. *Obviously* this new task is run as part of the `gulp npm-test` task, and thus through `npm test` on Node.js/Travis, such that it's still being tested as before.
Having thought *briefly* about using `css-vars-ponyfill`, I'm no longer convinced that it'd be a good idea. The reason is that if we actually want to properly support CSS variables, then that functionality should be available in *all* of our CSS files.
Note in particular the `pdf_viewer.css` file that's built as part of the `COMPONENTS` target, in which case I really cannot see how a rewrite-at-the-client solution would ever be guaranteed to always work correctly and without accidentally touching other CSS in the surrounding application.
All-in-all, simply re-writing the CSS variables at build-time seems much easier and is thus the approach taken in this patch; courtesy of https://github.com/MadLittleMods/postcss-css-variables
By using its `preserve` option, the built files will thus include *both* a fallback and a modern `var(...)` format[1]. As a proof-of-concept this patch removes a couple of manually added fallback values, and converts an additional sidebar related property to use a CSS variable.
---
[1] Comparing the `master` branch with this patch, when using `gulp generic`, produces the following diff for the built `web/viewer.css` file:
```diff
@@ -408,6 +408,7 @@
:root {
--sidebar-width: 200px;
+ --sidebar-transition-duration: 200ms;
}
* {
@@ -550,27 +551,28 @@
position: absolute;
top: 32px;
bottom: 0;
- width: 200px; /* Here, and elsewhere below, keep the constant value for compatibility
- with older browsers that lack support for CSS variables. */
+ width: 200px;
width: var(--sidebar-width);
visibility: hidden;
z-index: 100;
border-top: 1px solid rgba(51, 51, 51, 1);
-webkit-transition-duration: 200ms;
transition-duration: 200ms;
+ -webkit-transition-duration: var(--sidebar-transition-duration);
+ transition-duration: var(--sidebar-transition-duration);
-webkit-transition-timing-function: ease;
transition-timing-function: ease;
}
html[dir='ltr'] #sidebarContainer {
-webkit-transition-property: left;
transition-property: left;
- left: -200px;
+ left: calc(-1 * 200px);
left: calc(-1 * var(--sidebar-width));
}
html[dir='rtl'] #sidebarContainer {
-webkit-transition-property: right;
transition-property: right;
- right: -200px;
+ right: calc(-1 * 200px);
right: calc(-1 * var(--sidebar-width));
}
@@ -640,6 +642,8 @@
#viewerContainer:not(.pdfPresentationMode) {
-webkit-transition-duration: 200ms;
transition-duration: 200ms;
+ -webkit-transition-duration: var(--sidebar-transition-duration);
+ transition-duration: var(--sidebar-transition-duration);
-webkit-transition-timing-function: ease;
transition-timing-function: ease;
}
```
After PR 9566, which removed all of the old Firefox extension code, the `FIREFOX` build flag is no longer used for anything.
It thus seems to me that it should be removed, for a couple of reasons:
- It's simply dead code now, which only serves to add confusion when looking at the `PDFJSDev` calls.
- It used to be that `MOZCENTRAL` and `FIREFOX` was *almost* always used together. However, ever since PR 9566 there's obviously been no effort put into keeping the `FIREFOX` build flags up to date.
- In the event that a new, Webextension based, Firefox addon is created in the future you'd still need to audit all `MOZCENTRAL` (and possibly `CHROME`) build flags to see what'd make sense for the addon.
Currently *all* users of `pdfjs-dist` are forced to install the `webpack` and `worker-loader` packages, despite the fact that they are *only* relevant if the `webpack.js` file is being used (with a custom Webpack build).
This really doesn't seem great, especially since those packages are the only remaining dependencies in the `pdfjs-dist` library, and it thus seem more reasonable overall that Webpack users handle those dependencies themselves.
To prevent unnecessarily cryptic runtime failures, when people update to newer `pdfjs-dist` versions, the `webpack.js` file was updated to explicitly check for the existence of the `worker-loader` package and error otherwise.
Furthermore, note that `webpack` was only listed as a dependency because of the `worker-loader` package itself (see issue 9248).
Obviously these changes may not be seen as great by Webpack users who rely on `pdfjs-dist`, since it forces them to handle the dependencies themselves, however it should improve things considerably for "general" users of `pdfjs-dist` by not burdening them with unnecessary dependencies.
These sort of changes are also in line with other recent changes, see PR 11418, which removed built-in fake worker loader code for specific JS builders/bundlers/frameworks. This work was prompted not only by a desire to simplify/clean-up old code, but also to lessen future support burden since the PDF.js contributors cannot be assumed to be experts in various JS bundlers.
This patch makes the follow changes:
- Remove no longer necessary inline `// eslint-disable-...` comments.
- Fix `// eslint-disable-...` comments that Prettier moved down, thus causing new linting errors.
- Concatenate strings which now fit on just one line.
- Fix comments that are now too long.
- Finally, and most importantly, adjust comments that Prettier moved down, since the new positions often is confusing or outright wrong.
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.)
For performance reasons, and to avoid hanging the browser UI, the PDF.js library should *always* be used with web workers enabled.
At this point in time all of the supported browsers should have proper worker support, and Node.js is thus the only environment where workers aren't supported. Hence it no longer seems relevant/necessary to provide, by default, fake worker loaders for various JS builders/bundlers/frameworks in the PDF.js code itself.[1]
In order to simplify things, the fake worker loader code is thus simplified to now *only* support Node.js usage respectively "normal" browser usage out-of-the-box.[2]
*Please note:* The officially intended way of using the PDF.js library is with workers enabled, which can be done by setting `GlobalWorkerOptions.workerSrc`, `GlobalWorkerOptions.workerPort`, or manually providing a `PDFWorker` instance when calling `getDocument`.
---
[1] Note that it's still possible to *manually* disable workers, simply my manually loading the built `pdf.worker.js` file into the (current) global scope, however this's mostly intended for testing/debugging purposes.
[2] Unfortunately some bundlers such as Webpack, when used with third-party deployments of the PDF.js library, will start to print `Critical dependency: ...` warnings when run against the built `pdf.js` file from this patch. The reason is that despite the `require` calls being protected by *runtime* `isNodeJS` checks, it's not possible to simply tell Webpack to just ignore the `require`; please see [Webpack issue 8826](https://github.com/webpack/webpack) and libraries such as [require-fool-webpack](https://github.com/sindresorhus/require-fool-webpack).
*Please note:* This patch does *not* prevent the 'default_preferences' task from running more than once during `npm test`, but it does ensure that the tasks won't run *concurrently* by running the relevant tests in *series*.
While it would obviously still make sense to re-factor the gulpfile to account for changes in `gulp` version 4, by at least tweaking the `npm test` command the intermittent failures on Travis should at least go away.
Unfortunately I forgot to test `gulp mozcentraldiff` with PR 11256, which is really bad since it will cause the en-US `chrome.properties` l10n file to be deleted at mozilla-central; sorry about breaking this!
In order to address this we'll have to re-add (only) the en-US `chrome.properties` l10n file, which is simple enough. Furthermore, since we're not doing any sort of build-specific parsing of the l10n files, we can just copy the en-US files as-is rather than having to run `gulp locale` during `gulp mozcentral`.
With the removal of the (standalone) Firefox building code in PR 9566 (a year and a half ago), these files are now completely unused in the GitHub repository[1].
Hence it doesn't really seem necessary to keep fetching them with `gulp importl10n`, and the existing files in the `l10n` folder can also be removed (thanks to version control, they're easy enough to restore should the need ever arise).
The patch also allows an additional simplification, for the `gulp locale` and `gulp mozcentral` commands, since it's now possible to stop writing `l10n` files to the `extensions/firefox/` folder and instead just copy them similar to other build targets.
---
[1] They're obviously still used in `mozilla-central`, for fallback messages displayed through `PdfStreamConverter.jsm`, but that doesn't make it necessary to keep them *here* as far as I'm concerned.
With the removal of the (standalone) Firefox building code in PR 9566 (a year and a half ago), these files are now completely unused.
Hence it doesn't really make sense to keep building them as part of `gulp locale`, and the existing files in the `l10n` folder can also be removed (thanks to version control, they're easy enough to restore should the need ever arise).
The following is printed with every build, which gets kind of annoying when looking at the logs:
```
Replace Autoprefixer browsers option to Browserslist config.
Use browserslist key in package.json or .browserslistrc file.
Using browsers option cause some error. Browserslist config
can be used for Babel, Autoprefixer, postcss-normalize and other tools.
If you really need to use option, rename it to overrideBrowserslist.
Learn more at:
https://github.com/browserslist/browserslist#readmehttps://twitter.com/browserslist
```
Given how we're using Autoprefixer, with a number of build-specific configs, simply changing the option name seems like the easiest solution here.
(I'm also adding a couple of newlines at the `autoprefixer` call-sites, to aid readability.)
Compared to the recently replaced `URL` polyfill, the new `ReadableStream` polyfill isn't being exported globally for two reasons:
- We're currently checking for the existence of a global `ReadableStream` implementation when determining if the Fetch API will be used; please see `isFetchSupported` in the src/display/display_utils.js file.
- Given that it's much newer functionality (compared to `URL`) and that not all browsers may implement all parts of the specification yet, not exposing the `ReadableStream` globally seems safer for now.
Note how at https://mozilla.github.io/pdf.js/api/ it's being described as API docs, however `src/core/annotation.js` is not part of the public API.
Furthermore, given that the code residing in the `src/core/` folder is run in a worker-thread, it's not even accessible on the main-thread (since `postMessage` is being used to transfer the data).
Hence the different API methods simply returns a "proxy" to the underlying data, but not actually the same objects and data structures as in the worker-thread itself; thus it doesn't make a whole lot of sense to expose this in API docs as far as I'm concerned.
Finally, the patch fixes a small JSDoc related typo in `src/display/api.js` when referring to the `TextStyle` typedef.
