This essentially extends PR 11218 to also apply when looking up the final font-reference, via the XRef-table, fails because the font isn't available.
This patch also changes `PartialEvaluator.fallbackFontDict` to simply use "Helvetica" as the default font-name, since that seems generally reasonable given the now existing font-substitution code.
Given that the `css` property isn't constant, since it contains document/font ids, we cannot just check it directly. However, we can make use of regular expressions to ensure that the format is generally correct.
Originally the `PDFSidebarResizer` class was slightly larger, since the code used to contain e.g. feature testing for older (and no longer supported) browsers.
Given that there's some amount of overlap, when it comes to what DOM-elements and state that these classes need, it now seems reasonable to simply move the sidebar-resizing into the `PDFSidebar` class.
For the MOZCENTRAL build-target this patch reduces the size of the *built* `web/viewer.js` file by just over `1.1` kilobytes.
On my computer, it takes few tenths of a second to load a local font.
Since a font can be used several times in a document, the cache will
improve performances.
The /Decode-implementation in the our JPEG decoder, i.e. `src/core/jpg.js`, seems to only handle *inverting* of images properly. To support arbitrary /Decode-entries correctly we'll always use the `PDFImage.decodeBuffer` method, even for "simple" JPEG images, which should be fine since non-default /Decode-entries aren't a very common occurrence.
*Please note:* This patch will lead to a little bit of movement in some existing test-cases, however it should be virtually imperceivable to the naked eye.
While this slightly reduces duplication in the CSS rules, some of the auto-formatting done by Prettier is perhaps not great. (Given the overall advantage of using Prettier, we'll probably have to simply accept this.)
Some arabic chars like \ufe94 could be searched in a pdf, hence it must be normalized
when creating the search query. So to avoid to duplicate the normalization code,
everything is moved in the find controller.
The previous code to normalize text was using NFKC but with a hardcoded map, hence it
has been replaced by the use of normalize("NFKC") (it helps to reduce the bundle size
by 30kb).
In playing with this \ufe94 char, I noticed that the bidi algorithm wasn't taking into
account some RTL unicode ranges, the generated font wasn't embedding the mapping this
char and the unicode ranges in the OS/2 table weren't up-to-date.
When normalized some chars can be replaced by several ones and it induced to have
some extra chars in the text layer. To avoid any regression, when copying some text
from the text layer, a copied string is normalized (NFKC) before being put in the
clipboard (it works like this in either Acrobat or Chrome).
*Please note:* This patch only extends the `PDFFindController` implementation itself to support this functionality, however it's *purposely* not exposed in the default viewer.
This replaces the previous `phraseSearch`-parameter, and a `query`-string will now always be interpreted as a phrase-search.
To enable searching for individual words, the `query`-parameter must instead consist of an Array of strings. This way it's now also possible to combine phrase/word searches, with a `query`-parameter looking something like `["Lorem ipsum", "foo", "bar"]` which will search for the phrase "Lorem ipsum" *and* the words "foo" respectively "bar".
Currently we have two separate image-caches on the worker-thread:
- A local one, which is unique to each `PartialEvaluator.getOperatorList` invocation. This one caches both names *and* references, since image-resources may be accessed in either way.
- A global one, which applies to the entire PDF documents and all its pages. This one only caches references, since nothing else would work.
This patch introduces a third image-cache, which essentially sits "between" the two existing ones. The new `RegionalImageCache`[1] will be usable throughout a `PartialEvaluator` instance, and consequently it *only* caches references, which thus allows us to keep track of repeated image-resources found in e.g. different /Form and /SMask objects.
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[1] For lack of a better word, since naming things is hard...
*Please note:* This parameter has never been used within the PDF.js library/viewer itself, and it was only ever added for backwards compatibility reasons.
This parameter was added in PR 7475, over six years ago, to try and optionally maintain the previous *default* text-extraction behaviour.
However as part of the general text-extraction improvements in PR 13257, almost two years ago, the `disableCombineTextItems` functionality was accidentally "broken" in various ways. Note how the only (very basic) unit-test was updated in a way that doesn't really make sense, since generally speaking you'd expect that using the option should result in *more* (or at least the same number of) text-items. Furthermore there's also the recent issue 16209, where the option causes almost all textContent to be concatenated together.
Hence this patch proposes that we simply remove the `disableCombineTextItems` option since it's essentially unused/untested functionality, as evident from the fact that it took almost two years for someone to notice that it's broken.
