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).
This functionality was only added to the default viewer for backwards compatibility and to support the various PDF viewer tests in mozilla-central, with the intention to eventually remove it completely.
While the different mozilla-central tests cannot be *easily* converted from DOM events, it's however possible to limit that functionality to only MOZCENTRAL builds *and* when tests are running.
Rather than depending of the re-dispatching of internal events to the DOM, the default viewer can instead be used in e.g. the following way:
```javascript
document.addEventListener("webviewerloaded", function() {
PDFViewerApplication.initializedPromise.then(function() {
// The viewer has now been initialized, and its properties can be accessed.
PDFViewerApplication.eventBus.on("pagerendered", function(event) {
console.log("Has rendered page number: " + event.pageNumber);
});
});
});
```
The correct/intended way of working with the "viewer components" is by providing an `EventBus` instance upon initialization, and the `getGlobalEventBus` was only added for backwards compatibility.
Note, for example, that using `getGlobalEventBus` doesn't really work at all well with a use-case where there's *multiple* `PDFViewer` instances on a one page, since it may then be difficult/impossible to tell which viewer a particular event originated from.
All of the "viewer components" examples have been previously updated, such that there's no longer any code/examples which relies on the now removed `getGlobalEventBus` functionality.
It occured to me that similar to the `getGlobalEventBus` function, it's probably a good idea to *also* notify users of the fact that `eventBusDispatchToDOM` is now deprecated.
Rather than depending of the re-dispatching of internal events to the DOM, the default viewer can instead be used in e.g. the following way:
```javascript
document.addEventListener("webviewerloaded", function() {
PDFViewerApplication.initializedPromise.then(function() {
// The viewer has now been initialized, and its properties can be accessed.
PDFViewerApplication.eventBus.on("pagerendered", function(event) {
console.log("Has rendered page number: " + event.pageNumber);
});
});
});
```
I overlooked this in PR 11631; sorry about that!
Also, ensure that `EventBus` instances *always* track "external" events using a boolean regardless of the actual option value.
Since the goal has always been, essentially since the `EventBus` abstraction was added, to remove all dispatching of DOM events[1] from the viewer components this patch tries to address one thing that came up when updating the examples:
The DOM events are always dispatched last, and it's thus guaranteed that all internal event listeners have been invoked first.
However, there's no such guarantees with the general `EventBus` functionality and the order in which event listeners are invoked is *not* specified. With the promotion of the `EventBus` in the examples, over DOM events, it seems like a good idea to at least *try* to keep this ordering invariant[2] intact.
Obviously this won't prevent anyone from manually calling the new *internal* viewer component methods on the `EventBus`, but hopefully that won't be too common since any existing third-party code would obviously use the `on`/`off` methods and that all of the examples shows the *correct* usage (which should be similarily documented on the "Third party viewer usage" Wiki-page).
---
[1] Looking at the various Firefox-tests, I'm not sure that it'll be possible to (easily) re-write all of them to not rely on DOM events (since getting access to `PDFViewerApplication` might be generally difficult/messy depending on scopes).
In any case, even if technically feasible, it would most likely add *a lot* of complication that may not be desireable in the various Firefox-tests. All-in-all, I'd be fine with keeping the DOM events only for the `MOZCENTRAL` target and gated on `Cu.isInAutomation` (or similar) rather than a preference.
[2] I wouldn't expect any *real* bugs in a custom implementation, simply based on event ordering, but it nonetheless seem like a good idea if any "external" events are still handled last.
To avoid outright breaking third-party usages of the "viewer components" the `getGlobalEventBus` functionality is left intact, but a deprecation message is printed if the function is invoked.
The various examples are updated to *explicitly* initialize an `EventBus` instance, and provide that when initializing the relevant viewer components.
This should hopefully be useful in environments where restrictive CSPs are in effect.
In most cases the replacement is entirely straighforward, and there's only a couple of special cases:
- For the `src/display/font_loader.js` and `web/pdf_outline_viewer.js `cases, since the elements aren't appended to the document yet, it shouldn't matter if the style properties are set one-by-one rather than all at once.
- For the `web/debugger.js` case, there's really no need to set the `padding` inline at all and the definition was simply moved to `web/viewer.css` instead.
*Please note:* There's still *a single* case left, in `web/toolbar.js` for setting the width of the zoom dropdown, which is left intact for now.
The reasons are that this particular case shouldn't matter for users of the general PDF.js library, and that it'd make a lot more sense to just try and re-factor that very old code anyway (thus fixing the `setAttribute` usage in the process).
This removes a couple of, thanks to preceeding code, unnecessary `typeof PDFJSDev` checks, and also fixes a couple of incorrectly implemented (my fault) checks intended for `TESTING` builds.
Please find additional details about the ESLint rule at https://eslint.org/docs/rules/prefer-const
Note that this patch is generated automatically, by using the ESLint `--fix` argument, and will thus require some additional clean-up (which is done separately).
Rather than having a copy of this regular expression in the `test/unit/api_spec.js` file, with a comment about keeping it up-to-date with the code in the viewer (note the incorrect file reference as well), we can just import it instead to simplify all of this.
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.)
Sometimes we also used `@return`, but `@returns` is what the JSDoc
documentation recommends. Even though `@return` works as an alias, it's
good to use the recommended syntax and to be consistent within the
project.
Rather than manually clamping the `width` here, we can just `export` an already existing helper function from `ui_utils.js` instead.
(Hopefully it will eventually be possible to replace this helper function with a native `Math.clamp` function, given that there exists a "Stage 1 Proposal" for adding such a thing to the ECMAScript specification.)
The intention with preferences such as `sidebarViewOnLoad`/`scrollModeOnLoad`/`spreadModeOnLoad` were always that they should be able to *unconditionally* override their view history counterparts.
Due to the way that these preferences were initially implemented[1], trying to e.g. force the sidebar to remain hidden on load cannot be guaranteed[2]. The reason for this is the use of "enumeration values" containing zero, which in hindsight was an unfortunate choice on my part.
At this point it's also not as simple as just re-numbering the affected structures, since that would wreak havoc on existing (modified) preferences. The only reasonable solution that I was able to come up with was to change the *default* values of the preferences themselves, but not their actual values or the meaning thereof.
As part of the refactoring, the `disablePageMode` preference was combined with the *adjusted* `sidebarViewOnLoad` one, to hopefully reduce confusion by not tracking related state separately.
Additionally, the `showPreviousViewOnLoad` and `disableOpenActionDestination` preferences were combined into a *new* `viewOnLoad` enumeration preference, to further avoid tracking related state separately.
When `firstVisibleElementInd === 0`, regardless of the number of views, there's no reason to attempt to backtrack at all since it's never possible to find an element before the *first* one anyway.
Previously a couple of different attempts at fixing this problem has been rejected, given how *crucial* this code is for the correct function of the viewer, since no one has thus far provided any evidence that the problem actually affects the default viewer[1] nor an example using the viewer components directly (without another library on top).
The fact that none of the prior patches contained even a *simple* unit-test probably contributed to the unwillingness of a reviewer to sign off on the suggested changes.
However, it turns out that it's possible to create a reduced test-case, using the default viewer, that demonstrates the error[2]. Since this utilizes a hidden `<iframe>`, please note that this error will thus affect Firefox as well.
Note that while errors are thrown when the hidden `<iframe>` loads, the default viewer doesn't break completely since rendering does start working once the `<iframe>` becomes visible (although the errors do break the initial Toolbar state).
Before making any changes here, I carefully read through not just the immediately relevant code but also the rendering code in the viewer (given it's dependence on `getVisibleElements`). After concluding that the changes should be safe in general, the default viewer was tested without any issues found. (The above being much easier with significant prior experience of working with the viewer code.)
Finally the patch also adds new unit-tests, one of which explicitly triggers the relevant code-path and will thus fail with the current `master` branch.
This patch also makes `PDFViewerApplication` slightly more robust against errors during document opening, to ensure that viewer/document initialization always completes as expected.
Please keep in mind that even though this patch prevents an error in `getVisibleElements`, it's still not possible to set the initial position/zoom level/sidebar view etc. when the viewer is hidden since rendering and scrolling is completely dependent[3] on being able to actually access the DOM elements.
---
[1] And hence the PDF Viewer that's built-in to Firefox.
[2] Copy the HTML code below and save it as `iframe.html`, and place the file in the `web/` folder. Then start the server, with `gulp server`, and navigate to http://localhost:8888/web/iframe.html
```html
<!DOCTYPE html>
<html>
<head>
<title>Iframe test</title>
<script>
window.onload = function() {
const button = document.getElementById('button1');
const frame = document.getElementById('frame1');
button.addEventListener('click', function(evt) {
frame.hidden = !frame.hidden;
});
};
</script>
</head>
<body>
<button id="button1">Toggle iframe</button>
<br>
<iframe id="frame1" width="800" height="600" src="http://localhost:8888/web/viewer.html" hidden="true"></iframe>
</body>
</html>
```
[3] This is an old, pre-exisiting, issue that's not relevant to this patch as such (and it's already being tracked elsewhere).
With modern JavaScript supporting block-scoped variables, it's no longer necessary to have large numbers of top-level variable definitions (especially when all variables are, implicitly, set to `undefined`).
Besides moving variable definintions, a number of them are also converted to `const` to help ensure that they cannot be *accidentally* modified in the code.
Finally, the `views.length` calculation is now cached *once* rather than being re-computed multiple times.
This patch is the first step to be able to eventually get rid of the `attachDOMEventsToEventBus` function, by allowing `EventBus` instances to simply re-dispatch most[1] events to the DOM.
Note that the re-dispatching is purposely implemented to occur *after* all registered `EventBus` listeners have been serviced, to prevent the ordering issues that necessitated the duplicated page/scale-change events.
The DOM events are currently necessary for the `mozilla-central` tests, see https://hg.mozilla.org/mozilla-central/file/tip/browser/extensions/pdfjs/test, and perhaps also for custom deployments of the PDF.js default viewer.
Once this have landed, and been successfully uplifted to `mozilla-central`, I intent to submit a patch to update the test-code to utilize the new preference. This will thus, eventually, make it possible to remove the `attachDOMEventsToEventBus` functionality.
*Please note:* I've successfully ran all `mozilla-central` tests locally, with these patches applied.
---
[1] The exception being events that originated on the `window` or `document`, since those are already globally available anyway.
*Another small piece of clean-up of code I've previously written; follow-up to PR 8775.*
Importing `createPromiseCapability`, and then using it in just *one* spot, seems unnecessary since the `waitOnEventOrTimeout` function may just as well return a regular `Promise` directly.
This builds on the scrolling mode work to add three buttons for joining
page spreads together: one for the default view, with no page spreads,
and two for spreads starting on odd-numbered or even-numbered pages.
Prior to this commit, if the vertical scroll bar is absent and the horizontal
scroll bar is present, a link to a particular point on the page which should
induce a horizontal scroll did not do so, because the absence of a vertical
scroll bar meant that the viewer was not recognized as the nearest scrolling
ancestor. This commit adds a check for horizontal scroll bars when searching
for the scrolling ancestor.
A couple of basic unit-tests are added, and a manual `isLandscape` check (in `web/base_viewer.js`) is also converted to use the helper function instead.
Rather than having two different (but connected) options for the textLayer, I think that it makes sense to try and unify this. For example: currently if `disableTextLayer === true`, then the value of `enhanceTextSelection` is simply ignored.
Since PDF.js version `2.0` already won't be backwards compatible in lots of ways, I don't think that we need to worry about migrating existing preferences here.
Unfortunately, as far as I can tell, we still need the ability to adjust certain viewer options depending on the browser environment in PDF.js version `2.0`. However, we should be able to separate this from the general compatibility code in the `src/shared/compatibility.js` file.
This rule is available from https://www.npmjs.com/package/eslint-plugin-mozilla, and is enforced in mozilla-central. Note that we have the necessary `Array`/`String` polyfills and that most cases have already been fixed, see PRs 9032 and 9434.
For sufficiently large page sizes, always limiting the minimum zoom level to 25% seem a bit too high. One example is pages, e.g. the first one, in:
Hence I think that it makes sense to lower `MIN_SCALE` slightly, since other PDF viewers (e.g. Adobe Reader) isn't limiting the minimum zoom level as aggressively. Obviously this will allow a greater number of pages to be visible at the same time in the viewer, but given that they will be small that shouldn't be an issue.
Note also that e.g. the `page-fit`/`page-width` zoom levels already allow `< MIN_SCALE` values, so I don't see why we shouldn't allow users the same functionality directly.
The only reason for adding this parameter in the first place, all the way back in PR 4074, was that the "maintain document position on zooming" feature was landed and backed out a couple of times before it finally stuck.
Hence it seemed, at the time, like a good idea to have a simple way to disable that behaviour. However, that was almost four years ago, and it's just not likely that we'd want/need to ever disable it now.
Furthermore I really cannot imagine why anyone would actually *want* to reset the position whenever zooming occurs, since it results in a quite annoying UX.
*So, to summarize:* Based on the above, I think that we should try to remove this parameter now. On the off chance that anyone complains, re-adding it shouldn't be difficult.
By making use of modern CSS features, in this case [CSS variables](https://developer.mozilla.org/en-US/docs/Web/CSS/Using_CSS_variables), implementing sidebar resizing is actually quite simple. Not only will the amount of added code be fairly small, but it should also be easy to maintain since there's no need for complicated JavaScript hacks in order to update the CSS. Another benefit is that the JavaScript code doesn't need to make detailed assumptions about the exact structure of the HTML/CSS code.
Obviously this will not work in older browsers, such as IE, that lack support for CSS variables. In those cases sidebar resizing is simply disabled (via feature detection), and the resizing DOM element hidden, and the behaviour is thus *identical* to the current (fixed-width) sidebar.
However, considering the simplicity of the implementation, I really don't see why limiting this feature to "modern" browsers is a problem.
Finally, note that a few edge-cases meant that the patch is a bit larger than what the basic functionality would dictate. Among those is first of all proper RTL support, and secondly (automatic) resizing of the sidebar when the width of the *entire* viewer changes. Another, pre-existing, issue fixed here is the incomplete interface of `NullL10n`.
*Please note:* This patch has been successfully tested in both LTR and RTL viewer locales, in recent versions of Firefox and Chrome.
Fixes 2072.
This patch introduces an abstract `BaseViewer` class, that the existing `PDFViewer` then extends. *Please note:* This lays the necessary foundation for the next patch.
This changes both `PDFViewer` and `PDFThumbnailViewer` to return early in the `pagesRotation` setters if the rotation doesn't change.
It also fixes an existing issue, in `PDFViewer`, that would cause errors if the rotation changes *before* the scale has been set to a non-default value.
Finally, in preparation for subsequent patches, it also refactors the rotation code in `web/app.js` to update the thumbnails and trigger rendering with the new `rotationchanging` event.
These changes consists mainly of replacing `var` with `let`/`const`, adding a couple of default parameters to function signatures, and finally converting `EventBus`/`ProgressBar` to proper classes.
This patch contains the following improvements:
- Only fetch the various document properties *once* per PDF file opened, and cache the result (in a frozen object).
- Always update the *entire* dialog at once, to prevent inconsistent UI state (issue 8371).
- Ensure that the dialog, and all its internal properties, are reset when `PDFViewerApplication.close` is called.
- Inline, and re-factor, the `getProperties` method in `open`, since that's the only call-site.
- Always overwrite the fileSize with the value obtained from `pdfDocument.getDownloadInfo`, to ensure that it's correct.
- ES6-ify the code that's touched in this patch.
Fixes 8371.
Please see http://eslint.org/docs/rules/object-shorthand.
For the most part, these changes are of the search-and-replace kind, and the previously enabled `no-undef` rule should complement the tests in helping ensure that no stupid errors crept into to the patch.
With the exception of just one test-case, all the current `ui_utils` unit-tests can run successfully on Node.js (since most of them doesn't rely on the DOM).
To get this working, I had to first of all add a new `LIB` build flag such that `gulp lib` produces a `web/pdfjs.js` file that is able to load `pdf.js` successfully.
Second of all, since neither `document` nor `navigator` is available in Node.js, `web/ui_utils.js` was adjusted slightly to avoid errors.
The patch also changes the `defaultFilename` to use the ES6 default parameter notation, and fixes the formatting of the JSDoc comment.
Finally, since `getPDFFileNameFromURL` currently has no unit-tests, a few basic ones are added to avoid regressions.
Note that as discussed on IRC, this makes the viewer slightly slower to load *only* in `gulp server` mode, however the difference seem slight enough that I think it will be fine.
The download method (and the PDF document properties) detect the
file name using `getPDFFileNameFromURL`. The title ought to also
display the PDF filename if available.
The regular expression incorrectly marked a group as capturing.
For `http://example.com/#file.pdf`, the expected result is "file.pdf",
but instead "document.pdf" was returned.
Using `else` after `return` is not necessary, and can often lead to unnecessarily cluttered code. By using the `no-else-return` rule in ESLint we can avoid this pattern, see http://eslint.org/docs/rules/no-else-return.
This is required to be able to use it in the annotation display code,
where we now apply it to sanitize the filename of the FileAttachment
annotation. The PDF file from https://bugzilla.mozilla.org/show_bug.cgi?id=1230933 has shown that some PDF generators include the path of the file rather than the filename, which causes filenames with weird initial characters. PDF viewers handle this differently (for example Foxit Reader just replaces forward slashes with spaces), but we think it's better to only show the filename as intended.
Additionally we add unit tests for the `getFilenameFromUrl` helper
function.
Apparently some PDF files can have annotations with `URI` entries ending with `null` characters, thus breaking the links.
To handle this edge-case of bad PDFs, this patch moves the already existing utility function from `ui_utils.js` into `util.js`, in order to fix those URLs.
Fixes 6832.
*This regressed in PR 5356.*
Rather than just backing out the offending code, this patch restores scrolling in PresentationMode by making the `overflow: hidden;` check optional and letting the callers that need it (e.g. `PDFFindController`) opt-in to use it.
Since some browsers render `null` characters, and others don't, this patch adds a way to remove them to prevent display issues in the viewer UI.
Given that documents may contain very long outlines, I've added a utility function to avoid creating a lot of unnecessary `RegExp` objects.
To avoid any future issues, this utility function is used for both the outline and the attachments.
Fixes 6416.
