This simplifies/consolidates the ESLint configuration slightly in the `src/` folder, and prevents the addition of any new files where `var` is being used.[1]
Hence we no longer need to manually add `/* eslint no-var: error */` in files, which is easy to forget, and can instead disable the rule in the `src/core/` files where `var` is still in use.
---
[1] Obviously the `no-var` rule can, in the same way as every other rule, be disabled on a case-by-case basis where actually necessary.
This should be helpful to easily determine the *exact* version of the viewer itself, when looking at a *built* `web/viewer.js` file.
Note that we're already including this information in other built files, such as e.g. `pdf.js`, `pdf.worker.js`, `pdf_viewer.js`, and `pdf.image_decoders.js`.
Previously this rule has been enabled in the `web/` folder, and in select files in the `src/` sub-folders.
In this case, enabling of this rule didn't actually require any further code changes.
Please find additional details about the ESLint rule at https://eslint.org/docs/rules/no-var
Previously this rule has been enabled in the `web/` folder, and in select files in the `src/` sub-folders.
Note that a number of the files in the `src/display/` folder were already enforcing the `no-var` rule, and thanks to Prettier the necessary re-writing will be (mostly) handled automatically.
Please find additional details about the ESLint rule at https://eslint.org/docs/rules/no-var
This adds a new `PDFViewerApplication.triggerPrinting` method, which takes care of checking that printing is actually supported before calling `window.print`, to remove the need to duplicate that code in multiple places.
Also, removes the `PDFViewerApplication.printing` getter since it's not really necessary any more.
For now we need to use a Babel-plugin, since part of our build system doesn't support this fully (e.g. Babel-loader, Webpack 4.x, and SystemJS).
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/Optional_chaining
This release contains support for additional modern ECMAScript features, such as e.g. the nullish coalescing operator `??` and the optional chaining operator `?.`.
Given how those are used, there *should* not be any situation in which e.g. `undefined` is ever returned. However, actually checking that the pageView/thumbnail is defined cannot hurt.
Also, re-factor `webViewerPageRendered` slightly since the `pageView` is no longer unconditionally necessary after the previous patches; note in particular that the thumbnails will only be updated when the sidebar *and* the thumbnailView is visible.
Finally, fixes a bug in `webViewerPageChanging` whereby an empty string would not be treated as a valid pageLabel and instead be replaced by `null`.
Given that the default viewer only uses the "page stats" when debugging is enabled, it seems much simpler and more straightforward to simply query the API *directly* when this information is actually required. That way, there's a bit less information that needs to be stored/updated on each `PDFPageView`-instance.
Finally, since the `EventBus` now exists, we no longer need to handle the "page stats"-case in the regular listeners in `web/app.js`, but can instead add special "page stats"-listeners only when debugging is enabled.
The way that rendering errors are handled in `PDFPageView` is *very* old, and predates e.g. the introduction of the `EventBus` by several years.
Hence we should be able to simplify things a bit here, by including the Error (when it exists) in the "pagerendered" event and thus avoid having to reach into `PDFPageView` for it.
Note that a `RenderingCancelledException` *should* never actually reach this method, but better safe than sorry I suppose, considering that both `PDFPageView` and `PDFThumbnailView` are already catching `RenderingCancelledException`s since those are *not* Errors in the normal sense of the word.
This changes the `transformOrigin` calculations in `AnnotationElement._createContainer` and `PopupAnnotationElement.render`, to ensure that e.g. the clickable area of annotations and/or popups are both positioned correctly.
The problem occurs for *negative* values, since they're not negated correctly because of how the `transformOrigin` strings were build; see issue 12406 for a more in-depth explanation. Previously, for negative values, the `transformOrigin` strings would thus be ignored since they're not valid.
Given that the long-standing `webpack-stream` issue 201 was recently fixed in PR 207, and a new version released, we should now finally be able to update the dependency.
However, depending on if/when `webpack-stream` gets support for Webpack 5 (which is currently in beta) we may still want remove our `webpack-stream` dependency.
