The `getPageSizeInches` method was implemented on `PDFDocumentProxy`, which seems conceptually wrong since the size property isn't global to the document but rather specific to each page. Hence the method is moved into `PDFPageProxy`, as `get pageSizeInches` instead to address this.
Despite the fact that new API functionality was implemented, no unit-tests were added. To prevent issues later on, we should *always* ensure that new functionality has at least some test-coverage; something that this patch also takes care of.
The new `PDFDocumentProperties._parsePageSize` method seemed unnecessary convoluted. Furthermore, in the "no data provided"-case it even returned incorrect data (an array, rather than the expected object).
Finally, the fallback strings didn't actually agree with the `en-US` locale. This inconsistency doesn't look too great, and it's thus addressed here as well.
With options being moved from the global `PDFJS` object and into `getDocument`, a side-effect is that we're now passing in a fair number of useless parameters to the various transport/network streams.
Even though this doesn't *currently* cause any problems, it nonetheless seem like a good idea to explicitly provide the parameters that are actually necessary.
One additional complication with removing this option from the global `PDFJS` object, is that the viewer currently needs to check `disableAutoFetch` in a couple of places. To address this I'm thus proposing adding a getter in `PDFDocumentProxy`, to allow checking the *actually* used values for a particular `getDocument` invocation.
Unfortunately, as far as I can tell, we still need the ability to adjust certain API 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.
Compared to most other options currently/previously residing on the global `PDFJS` object, some of the Worker specific ones (e.g. `workerPort`/`workerSrc`) probably cannot be moved into options provided directly when initializing e.g. `PDFWorker`.
The reason is that in some cases, e.g. the Webpack examples, we try to provide Worker auto-configuration and I cannot see a good solution for that use-case if we completely remove the globally available Worker configuration.
However inline with previous patches for PDF.js version `2.0`, it does seem like a worthwhile goal to move away from storing options directly on the global `PDFJS` object, since that is a pattern we should avoid going forward. Especially since one of the (eventual) goals is to attempt to *completely* remove the global `PDFJS` object, and rely solely on exporting/importing the needed functionality.
By introducing the `GlobalWorkerOptions` we thus have larger flexibility in the future, if/when the global `PDFJS` object will be removed.
In order to simplify things, the undocumented `enableStats` option was removed and `pdfBug` is now instead used to enabled general debugging *and* page request/rendering stats.
Considering that in the default viewer the `stats` was only used when debugging was also enabled, this simplification (code wise) definitely seem worthwhile to me.
This removes the `PDFJS.externalLinkTarget`/`PDFJS.externalLinkRel` dependency from the viewer components, but please note that as a *temporary* solution the default viewer still uses it.
This removes the `PDFJS.imageResourcesPath` dependency from the viewer components and the test-suite, but please note that as a *temporary* solution the default viewer still uses it.
Fallback to the built-in JPEG decoder when browser decoding fails, and attempt to handle JPEG images with DNL (Define Number of Lines) markers (issue 8614)
First of all, note how in both `fetch_stream.js` and `node_stream.js` we always overwrite the `this._contentLength` property even when the response headers doesn't actually contain any (valid) length information. This could thus result in the `length` parameter, as passed to the network stream, being completely ignored despite having no better information available.
Secondly, in `node_stream.js` the `this._isRangeSupported` property wasn't always updated correctly based on the response headers.
This works by making `PartialEvaluator.buildPaintImageXObject` wait for the success/failure of `loadJpegStream` on the API side *before* parsing continues.
Please note that in practice, it should be quite rare for the browser to fail loading/decoding of a JPEG image. In the general case, it should thus not be completely surprising if even `src/core/jpg.js` will fail to decode the image.
Since `loadJpegStream` is only used at a *single* spot in the code-base, and given that it's very heavily tailored to the calling code (since it relies on the data structure of `PDFObjects`), this patch simply inlines the code in `src/display/api.js` instead.
Despite this patch removing the `disableWorker` option itself, please note that we'll still fallback to loading the worker file(s) on the main-thread when running in environments without proper Web Worker support.
Furthermore it's still possible, even with this patch, to force the use of fake workers by manually loading the necessary file using a `<script>` tag on the main-thread.[1]
That way, the functionality of the now removed `SINGLE_FILE` build target and the resulting `build/pdf.combined.js` file can still be achieved simply by adding e.g. `<script src="build/pdf.worker.js"></script>` to the HTML (obviously with the path adjusted as needed).
Finally note that the `disableWorker` option is a performance footgun, and unfortunately many existing third-party examples actually use it without providing any sort of warning/justification.
---
[1] This approach is used in the default viewer, since certain kind of debugging may be easier if the code is running directly on the main-thread.
This method returns the currently used `workerSrc`, which thus allows obtaining the fallback `workerSrc` value (e.g. when the option wasn't set by the user).
Please note that this build target, and the resulting `build/pdf.combined.js` file, is equivalent to setting the `PDFJS.disableWorker` option to `true` which is a performance footgun.
It turns out that PR 9245 unfortunately broke benchmarking completely, sorry about that!
The bug is that we were attempting to reset the current instance of `StatTimer`, instead of creating a new one as was previously done. By resetting the current instance, the `StatTimer` data fetched in `test/driver.js` is now wiped out since it points to the *same* underlying object.
This re-use of a `StatTimer` instance was asked for during review, and unfortunately I didn't test this thoroughly enough before submitting the final version of the PR.[1]
---
[1] Note that while I did test the benchmarking scripts with that PR *before* initially submitting it, I did however forget to do that after addressing the review comments which might explain why this problem went unnoticed.
