Currently we simply use the Babel `preset-env` in the `legacy`-builds of the PDF.js library. This has the side-effect of transpiling the code for *very old* browsers/environments, including ones that we (since many years) no longer support which unnecessarily bloats the size of the `legacy`-builds.
For the CSS files we're only targeting *the supported browsers*, and it's thus possible to extend that to also apply to Babel.
One of the most significant changes, with this patch, is that we'll no longer polyfill `async`/`await` in the `legacy`-builds. However, this shouldn't be an issue given the browsers that we currently support in PDF.js; please refer to:
- https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support
- https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/async_function#browser_compatibility
Currently in `disableWorker=true` mode it's possible that opening of password-protected PDF documents outright fails, if an *incorrect* password is entered. Apparently the event ordering is subtly different in the non-Worker case, which causes the password-callback to be updated *before* the dialog has been fully closed.
To avoid that we'll utilize a `PromiseCapability` to keep track of the state of the password dialog, such that we can delay both re-opening and (importantly) updating of the password-callback until doing so is safe.
This patch *may* also fix issue 15330, but it's impossible for me to tell.
*This is a follow-up to PR 14869.*
In the old code we're accidentally "swallowing" part of the event-details, which explains why the annotationLayer didn't render.
One thing that made debugging a lot harder was the lack of error messages, from the viewer, and a few `PDFPageView`-methods were updated to improve this situation.
- Remove the `typeof Worker` check, since all browsers have had `Worker` support for many years now; see https://developer.mozilla.org/en-US/docs/Web/API/Worker#browser_compatibility
Furthermore the `new Worker(...)` call is wrapped in try-catch, which means that we'll still fallback to "fake workers" if necessary.
- Limit the `fallbackWorkerSrc` handling, in the `PDFWorker.workerSrc` getter, to only GENERIC builds since that's the only place where it's defined anyway.
Given that the code is written with JavaScript module-syntax, none of this functionality will "leak" outside of this file with these change.
By removing this closure the file-size is decreased, even for the *built* `pdf.worker.js` file, since there's now less overall indentation in the code.
This was moved into the `src/display/`-folder in PR 15110, for the initial editor-a11y patch. However, with the changes in PR 15237 we're again only using `binarySearchFirstItem` in the `web/`-folder and it thus seem reasonable to move it back there.
The primary reason for moving it back is that `binarySearchFirstItem` is currently exposed in the public API, and we always want to avoid that unless it's either PDF-related functionality or code that simply must be shared between the `src/`- and `web/`-folders. In this case, `binarySearchFirstItem` is a general helper function that doesn't really satisfy either of those alternatives.
Currently when the `TextAccessibilityManager.enabled` method is called, we'll update `aria-owns` for any pre-existing elements. This obviously makes sense when e.g. zooming/rotating in the viewer, since the annotationLayer/annotationEditorLayer is kept in those cases.
However when the page is *fully* reset, e.g. as result of going out-of-view and thus being evicted from the cache, we still keep the `#textNodes`-Map around. This causes us to set the `aria-owns` attribute (in the textLayer) for an element that doesn't actually exist any more, which as far as I'm concerned seems incorrect. In this case the element will simply, as already implemented, be re-inserted when the annotationLayer/annotationEditorLayer renders again.
Given that the code is written with JavaScript module-syntax, none of this functionality will "leak" outside of this file with these changes.
For e.g. the `gulp mozcentral` command the *built* `pdf.worker.js` file-size decreases `~2 kB` with this patch, and most of the improvement comes from having less overall indentation in the code.
Given that the code is written with JavaScript module-syntax, none of this functionality will "leak" outside of this file with these changes.
By removing this closure the file-size is decreased, even for the *built* `pdf.worker.js` file, since there's now less overall indentation in the code.
This patch doesn't structurally change the text layer: it just adds some aria-owns
attributes to some spans.
The aria-owns attribute expect to have an element id, hence it's why it adds back an
id on the element rendering an annotation, but this id is built in using crypto.randomUUID
to avoid any potential issues with the hash in the url.
The elements in the annotation layer are moved into the DOM in order to have them in the
same "order" as they visually are.
The overall goal is to help screen readers to present to the user the annotations as
they visually are and as they come in the text flow.
It is clearly not perfect, but it should improve readability for some people with visual
disabilities.
According to MDN `Path2D` is available in all browsers that we currently support, see https://developer.mozilla.org/en-US/docs/Web/API/Path2D#browser_compatibility
Hence only Node.js is currently lagging behind here, and requires that we keep the old code as a fallback in the `compileType3Glyph` function. However, there's an open PR in the `node-canvas` repository for adding `Path2D` support.
As far as I'm concerned, there's two possible solutions here:
- We land this patch now, since it removes unnecessary code in e.g. the Firefox PDF Viewer, which means that compilation of Type3 glyphs will be disabled in Node.js until that PR is landed.[1]
If users report bugs about Type3 glyphs looking "inconsistent" in Node.js and/or being slow to render, we could perhaps encourage them to upvote and otherwise help out getting that PR landed?
- We wait for the mentioned PR to land *first*, before moving forward with this patch. Given that there's been no updates on that PR for almost two months, this alternative may possibly take a while.
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[1] Note that Type3 fonts are first of all not very common in PDF documents, and secondly that compilation only applies specifically to Type3 glyphs that contain /ImageMask-data (i.e. not all Type3 fonts are affected).
This exports the same constants as the viewer components, but in the default viewer. To avoid bloating the global-scope the constants are added to a new `PDFViewerApplicationConstants` object[1], which also allows us to skip this in builds where it's not actually needed (e.g. the Firefox *built-in* PDF Viewer).
*Please note:* I'm not completely sold on this idea, and thus wouldn't mind the patch being rejected, since we probably don't want to export every single viewer constant this way. (And it may seem a bit arbitrary, to users, why some constants are exported and others are not.)
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[1] Somewhat similar to the existing `PDFViewerApplicationOptions` structure.
In addition to the existing `LinkTarget` constant, used by the `PDFLinkService`-constructor, this patch exports the following constants in the viewer components:
- `ScrollMode` and `SpreadMode`, since the `BaseViewer` has getters/setters which work with those constants.
- `RenderingStates`, since that one may be helpful when using `PDFPageView` directly.
While this has always worked, as a consequence of the implementation, it's never been officially supported.
In addition to adding basic unit-tests, this patch also introduces a couple of new JSDoc `@typedef`s in the API to avoid overly long lines.
By invoking the `reset` methods *last* in the `Toolbar`/`SecondaryToolbar`-constructors, we ensure that the "toolbarreset"/"secondarytoolbarreset"-events are actually handle when the viewer loads. Note that previously those events were dispatched *before* the relevant event-listeners had been attached.
With this small change we can avoid inconsistent initial toolbar-state, specifically in the case when the viewer is *reloaded* (since Firefox keeps the HTML-state on "soft" reloads).
