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.
*After browsing through (a version of) the JPEG specification, see https://www.w3.org/Graphics/JPEG/itu-t81.pdf, I hope that this patch makes sense.*
Note that while issue 7828 became a problem after PR 7661, it isn't really a regression from than PR. The explanation is rather that we're now relying on `core/jpg.js` instead of the Native Image decoder in more situations than before, which thus exposed an *existing* issue in our JPEG decoder.
Another factor also seems to be that in many JPEG images, the DRI (Define Restart Interval) marker isn't present, in which case this bug won't manifest either.
According to https://www.w3.org/Graphics/JPEG/itu-t81.pdf#page=89 (at the bottom of the page):
"NOTE – The final restart interval may be smaller than the size specified by the DRI marker segment, as it includes only the number of MCUs remaining in the scan."
Furthermore, according to https://www.w3.org/Graphics/JPEG/itu-t81.pdf#page=39 (in the middle of the page):
"[...] If restart is enabled and the restart interval is defined to be Ri, each entropy-coded segment except the last one shall contain Ri MCUs. The last one shall contain whatever number of MCUs completes the scan."
Based on the above, it thus seem to me that we should simply ensure that we're not attempting to continue to parse Scan data once we've found all MCUs (Minimum Coded Unit) of the image.
Fixes 7828.
I happened to notice that some inequalities had the wrong order, and was surprised since I thought that the `yoda` rule should have caught that.
However, reading http://eslint.org/docs/rules/yoda#options a bit more closely than previously, it's quite obvious that the `onlyEquality` option does *exactly* what its name suggests. Hence I think that it makes sense to adjust the options such that only ranges are allowed instead.
*This is something that I noticed while working on PR 8126, which is (more) fallout from PR 6065.*
In general, it's actually *not* correct to return `Dict.empty` as the default value for non-existent properties. Please note that a prior PR, see https://github.com/mozilla/pdf.js/pull/5957#issuecomment-103112698, asked for that behaviour but I don't think that's right.
Obviously for properties that are (or should) be `Dict`s it makes sense, however certain properties can be e.g. Strings or Arrays instead. In the latter case, returning `Dict.empty` is just plain wrong, and it's quite fascinating that this hasn't caused any errors in practice. (The existing validation in the various getters has actually saved us here.)
Also, when looking at this code again, it seemed unnecessary to duplicate the `MAX_LOOP_COUNT` check since we could just return immediately instead.
When using content security headers to restrict connections to the same origin,
you may not make connections to `example.com`. This feature detection also
works with a request to the current location.
It appears that I accidentally broke this in PR 6065, sorry about that!
The issue in this particular PDF file is that there's `/Rotate` entries on different levels of the `/Pages` tree. We're supposed to use the `/Rotate` entry in the `/Page` dict (which is `0`), but because of an incorrect condition we instead ended up with the one from the `/Pages` dict (which is `180`).
Fixes 8125.
Ideally, the `Annotation` class should not have anything to do with the
page's operator list. How annotations are added to the page's operator
list is logic that belongs in `src/core/document.js` instead where the
operator list is constructed.
Moreover, some comments have been added to clarify the intent of the
code.
