This patch adds Streams API support in getTextContent
so that we can stream data in chunks instead of fetching
whole data from worker thread to main thread. This patch
supports Streams API without changing the core functionality
of getTextContent.
Enqueue textContent directly at getTextContent in partialEvaluator.
Adds desiredSize and ready property in streamSink.
The `ObjectLoader` currently takes an Object as input, despite actually working with `Dict`s internally. This means that at the (two) existing call-sites, we're passing in the "private" `Dict.map` property directly.
Doing this seems like an anti-pattern, and we could (and even should) simply provide the actual `Dict` when creating an `ObjectLoader` instance.
Accessing properties stored in the `Dict` is now done using the intended methods instead, in particular `getRaw` which (as the name suggests) doesn't do any de-referencing, thus maintaining the current functionality of the code.
The only functional change in this patch is that `ObjectLoader.load` will now ignore empty nodes, such that `ObjectLoader._walk` only needs to deal with nodes that are known to contain data. (This lets us skip, among other checks, meaningless `addChildren` function calls.)
*As mentioned the last time that I touched this particular part of the font code, I'm sincerely hope that this doesn't cause any regressions!*
However, the patch passes all tests added in PRs 5770, 6270, and 7904 (and obviously all other tests as well). Furthermore, I've manually checked all the issues/bugs referenced in those PRs without finding any issues.
Fixes 8480.
Please note that the `glyphlist.js` and `unicode.js` files are converted to CommonJS modules instead, since Babel cannot handle files that large and they are thus excluded from transpilation.
PR 7341 added special handling for `nameddest`s that look like pageNumbers, to prevent issues since we previously *incorrectly* supported specifying a pageNumber directly in the hash; i.e. `#10` versus the correct `#page=10` format.
Since this behaviour wasn't correct, PR 7757 fixed and deprecated the old format, which means that we no longer need to maintain the `nameddest` hack in multiple files.
For some reason, we're putting all kind of images *except* JPEG into the `imageCache` in `evaluator.js`.[1]
This means that in the PDF file in issue 8380, we'll keep sending the *same* two small images[2] to the main-thread and decoding them over and over. This is obviously hugely inefficient!
As can be seen from the discussion in the issue, the performance becomes *extremely* bad if the user has the addon "Adblock Plus" installed. However, even in a clean Firefox profile, the performance isn't that great.
This patch not only addresses the performance implications of the "Adblock Plus" addon together with that particular PDF file, but it *also* improves the rendering times considerably for *all* users.
Locally, with a clean profile, the rendering times are reduced from `~2000 ms` to `~500 ms` for my setup!
Obviously, the general structure of the PDF file and its operator sequence is still hugely inefficient, however I'd say that the performance with this patch is good enough to consider the issue (as it stands) resolved.[3]
Fixes 8380.
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[1] Not technically true, since inline images are cached from `parser.js`, but whatever :-)
[2] The two JPEG images have dimensions 1x2, respectively 4x2.
[3] To make this even more efficient, a new state would have to be added to the `QueueOptimizer`. Given that PDF files this stupid fortunately aren't too common, I'm not convinced that it's worth doing.
Currently these methods accept a large number of parameters, which creates quite unwieldy call-sites. When invoking them, you have to remember not only what arguments to supply, but also the correct order, to avoid runtime errors.
Furthermore, since some of the parameters are optional, you also have to remember to pass e.g. `null` or `undefined` for those ones.
Also, adding new parameters to these methods (which happens occasionally), often becomes unnecessarily tedious (based on personal experience).
Please note that I do *not* think that we need/should convert *every* single method in `evaluator.js` (or elsewhere in `/core` files) to take parameter objects. However, in my opinion, once a method starts relying on approximately five parameter (or even more), passing them in individually becomes quite cumbersome.
With these changes, I obviously needed to update the `evaluator_spec.js` unit-tests. The main change there, except the new method signatures[1], is that it's now re-using *one* `PartialEvalutor` instance, since I couldn't see any compelling reason for creating a new one in every single test.
*Note:* If this patch is accepted, my intention is to (time permitting) see if it makes sense to convert additional methods in `evaluator.js` (and other `/core` files) in a similar fashion, but I figured that it'd be a good idea to limit the initial scope somewhat.
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[1] A fun fact here, note how the `PartialEvaluator` signature used in `evaluator_spec.js` wasn't even correct in the current `master`.
Note that by using `let` instead of `var` in `PartialEvaluator.setGState` and `TranslatedFont.loadType3Data`, we can get rid of further `bind` usages since `let` is block-scoped.
Also, the fact that `bind` wasn't used in the `Font` case inside of `setGState` is actually a bug which has been present ever since PR 5205, where a closure was replaced by a standard loop.[1]
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[1] I'm not aware of any bugs caused by this, but that is probably more a happy accident than anything else, since e.g. just removing the `bind` from the `SMask` case without using block-scoped variables causes test failures.
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.
Please refer to the JBIG2 standard, see https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-T.88-200002-I!!PDF-E&type=items.
In particular, section "6.3.5.3 Fixed templates and adaptive templates" mentions that the offsets should be *subtracted*; where the offsets are defined according to "Table 6" under section "6.3.2 Input parameters".
Fixes 7145.
Fixes 7308.
Fixes 7401.
Fixes 7850.
Fixes 8270.
[api-minor] Always allow e.g. rendering to continue even if there are errors, and add a `stopAtErrors` parameter to `getDocument` to opt-out of this behaviour (issue 6342, issue 3795, bug 1130815)
This patch implements support for line annotations. Other viewers only
show the popup annotation when hovering over the line, which may have
any orientation. To make this possible, we render an invisible line (SVG
element) over the line on the canvas that acts as the trigger for the
popup annotation. This invisible line has the same starting coordinates,
ending coordinates and width of the line on the canvas.
Other PDF readers, e.g. Adobe Reader and PDFium (in Chrome), will attempt to render as much of a page as possible even if there are errors present.
Currently we just bail as soon the first error is hit, which means that we'll usually not render anything in these cases and just display a blank page instead.
NOTE: This patch changes the default behaviour of the PDF.js API to always attempt to recover as much data as possible, even when encountering errors during e.g. `getOperatorList`/`getTextContent`, which thus improve our handling of corrupt PDF files and allow the default viewer to handle errors slightly more gracefully.
In the event that an API consumer wishes to use the old behaviour, where we stop parsing as soon as an error is encountered, the `stopAtErrors` parameter can be set at `getDocument`.
Fixes, inasmuch it's possible since the PDF files are corrupt, e.g. issue 6342, issue 3795, and [bug 1130815](https://bugzilla.mozilla.org/show_bug.cgi?id=1130815) (and probably others too).
The display layer is responsible for creating the HTML elements for the
annotations from the core layer. If we need to ignore border styling for
the containers of certain elements, the display layer should do so and
not the core layer. I noticed this during the implementation of line
annotations, for which we actually need the original border width in the
display layer, even though we ignore it for the container. If we set the
border style to zero in the core layer, this becomes impossible.
To prevent this, this patch moves the container border removal code from
the core layer to the display layer. This makes the core layer output
the unchanged annotation data and lets the display layer remove any
border styling if necessary.
I happened to notice that the error handling wasn't that great, which I missed previously since there were no unit-tests for failure to load built-in CMap files.
Hence this patch, which improves the error handling *and* adds tests.
I found that PR 8105 unfortunately causes a *very serious* performance regression in long PDF documents where the `Pages` tree only has one level; my apologies for this!
Obviously we cannot revert that PR, since that would cause more issues than it solves. Hence it seems to me that the only viable solution here, is to add a simple `RefSetCache` to reduce the amount of redundant lookups.
Previously in PR 8105 caching was thought to be unnecessary, but as it turns out I don't think that we really have a choice in the matter any more.
For reasons I don't pretend to understand, we're passing around `xref` arguments to a bunch of methods despite `this.xref` being available in `PartialEvaluator`.
This patch is a small first small step towards cleaning up the, often unwieldy, signatures of methods in `PartialEvaluator`.
*My apologies for inadvertently breaking this in PR 8064; apparently we don't have any tests that cover this use-case :(*
Without this patch `getTextContent` will fail if called before `getOperatorList`, since loading of fonts during text-extraction may require fetching of built-in CMap files.
*Please note:* The `text` test added here, which uses an already existing PDF file, fails without this patch.
In core/document.js: `PDFDocument.prototype.parse` accesses a dictionary
property, which could throw if the underlying data is not yet available.
In core/obj.js: `get Catalog.prototype.metadata` calls
`stream.getBytes`, which can throw MissingDataException too when the
stream is a ChunkedStream.
Similar to other `try-catch` statements in `/core` code, we must re-throw `MissingDataException` to prevent issues with missing data during document loading.
Note that I'm not sure if/how we can test this, which is why the patch doesn't include any test(s).
Fixes 8180.
