If a PDF included an embedded TrueType font whose preferred character
map (cmap) was in "format 2", the code would select that character map
and then refuse to read it because of an unsupported format, thus
causing the characters not to be rendered. This commit implements
support for format 2 as described at the link below.
https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6cmap.html
This is unfortunately *yet another* bug in the `preEvaluateFont`-implementation, and I've lost count of the number of times I've had to tweak this code over the years :-(
I really cannot help thinking that PR 4423 was way too simplistic, since it missed a bunch of cases that leads to broken font rendering in many PDF documents.
Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1734802
Note how both the annotationLayer and the document outline will apply various URL-related options when creating the link-elements.
For consistency the `xfaLayer`-rendering should obviously use the same options, to ensure that the existing options are indeed applied to all URLs regardless of where they originate.
- it aims to fix#12721.
- Thanks to PR #14023, we've now the fieldObjects in the annotation layer so we can easily map fields names on their id if needed.
- Reset values in the storage, in the JS sandbox and in the visible html elements.
In the referenced bug, the embedded fonts contain custom CMap-data that only include strings. Note how for embedded composite TrueType fonts we're using the CMap-data when building the glyph mapping, and currently we end up with a completely empty map because the code expects only CID *numbers*.
Furthermore, just fixing the glyph mapping alone isn't sufficient to fully address the bug, since we also need to consider this "special" kind of CMap-data when looking up glyph widths.
Having recently worked with, and reviewed patches touching, this code it seemed that it's probably not a bad idea to move that functionality into `createValidAbsoluteUrl` as new options instead.
For the `addDefaultProtocolToUrl` functionality in particular, the existing helper function was not only moved but slightly improved as well. Looking at the code, I realized that there's a small risk that it would incorrectly match a *relative* URL-string too.
With these changes, the `createValidAbsoluteUrl` call-sites in the `src/core/`-code can be simplified a little bit.
*Please note:* This patch may, indirectly, change the format of the `unsafeUrl`-property returned with relevant Annotations and OutlineItems; hence the `api-minor` tag.
However, I'd argue that it's actually more correct this way since the whole purpose of `unsafeUrl` is/was to return the URL data as-is without any parsing done.
- it aims to fix https://bugzilla.mozilla.org/show_bug.cgi?id=1716758;
- some buttons have a JS action with the pattern `app.launchURL(...)` (or similar) so extract when it's possible the url and generate a <a> element with the href equals to the found url;
- pdf.js already had some code to handle that so this patch slightly refactor that.
- it aims to fix#14021;
- the N dict is empty here so just create a default one;
- it implies that the checked checkbox has no appearance so create a default one too in order to print it;
- in the pdf in the issue, a checked box is not printed because it has no default appearance so we need to guess its appearance from its state.
In order to implement this, we utilize the existing `bidi` function to infer the text-direction of /T and /Contents entries. While this may not be perfect in cases where one PopupAnnotation mixes LTR and RTL languages, it should work well enough in most cases.
To avoid having to add *two new* properties in lots of annotations, supplementing the existing `title`/`contents`-properties, this patch instead re-factors the existing code such that the properties are replaced by Objects (containing `str` and `dir`).
*Please note:* In order avoid breaking existing third-party implementations, `GENERIC`-builds of the PDF.js library will still provide the old `title`/`contents`-properties on annotations returned by `PDFPageProxy.getAnnotations`.
- In the pdf in issue #14071, some select fields don't contain any values;
- the corresponding node has a bindItems and a bind elements and _bindItems function was just not called.
With this patch we'll ensure that only valid absolute URLs can be used in XFA documents, similar to the existing validation done for "regular" PDF documents.
Furthermore, we'll also attempt to add a default protocol (i.e. `http`) to URLs beginning with "www." in XFA documents as well; this on its own is enough to fix https://bugzilla.mozilla.org/show_bug.cgi?id=1731240
Rather than re-computing this value in a number of different places throughout the code-base[1], we can expose this in the API via the existing `PixelsPerInch`-structure instead.
There's also been feature requests asking for the old `CSS_UNITS` viewer constant to be made accessible, such that it could be used in third-party implementations.
I suppose that it could be argued that it's somewhat confusing to place a unitless property in `PixelsPerInch`, however given that the `PDF_TO_CSS_UNITS`-property is defined strictly in terms of the existing properties this is hopefully deemed reasonable.
---
[1] These include:
- The viewer, with the `CSS_UNITS` name.
- The reference-tests.
- The display-layer, when rendering images; see PR 13991.
Currently we only exclude /Encoding entries that also contains a /Differences array, which is the cause of the text-selection problem in the referenced issue.
In order to address this we'll now also exclude /Encoding entries that contain one of the predefined *named* encodings, and no longer require that it also contains a /Differences array.
*Please note:* This patch cases a small "regression" in the `bug1130815-text` test-case, however this is actually an improvement when compared with Adobe Reader and PDFium (in Google Chrome).
- it aims to fix https://bugzilla.mozilla.org/show_bug.cgi?id=1719148;
- JS can set a property for a non-rendered annotation using the annotationStorage but the other unset default properties must be used when the annotation is finally rendered;
- so this patch just adds the properties already set in the annotationStorage to the default value.
Rather than forcing the "regular" `EventBus` to check and handle `isInAutomation` for every `dispatch` call, we can take advantage of subclassing instead.
Hence this PR introduces a new `AutomationEventBus` class, which extends `EventBus`, and is used by the default viewer when `isInAutomation === true`.
In this particular case the `CMap`-data that we create contains only numbers, but no strings, which causes `PartialEvaluator.readToUnicode` to create a ToUnicode-map with only empty strings.
*Please note:* This is yet another case where I don't know if it's necessarily the best and most correct solution, but it does fix the referenced issue.
- it aims to fix https://bugzilla.mozilla.org/show_bug.cgi?id=1722036.
- AS and V should share the same value for checkbox: it's at least what the specs say;
- the pdf in the above bug opens correctly in Acrobat so it likely means that AS is chosen over V.
*Please note:* All of this feels very handwavy, but at least it passes all tests locally. Hopefully we have enough tests for this part of the font code.
For non-embedded composite standard fonts with an "incomplete" /CIDToGIDMap, we'll now fallback to an *explicitly defined* /ToUnicode map even when that one happens to be an /Identity-H or /Identity-V map.
The `Font.fallbackToSystemFont` method is unfortunately getting more and more special-cases, however that might be unavoidable given all the weird non-embedded fonts found in the wild :-(
*This fixes something that I noticed, having recently looked at both the `Lexer.getObj` and `writeValue` code.*
Please note that I unfortunately don't have an example of a form where saving fails without this patch. However, given its overall simplicity and that unit-tests are added, it's hopefully deemed useful to fix this potential issue pro-actively rather than waiting for a bug report.
At this point one might, and rightly so, wonder if there's actually any real-world PDF documents where a `null` value is being used?
Unfortunately the answer is *yes*, and we have a couple of examples in the test-suite (although none of those are related to forms); please see: `issue1015`, `issue2642`, `issue10402`, `issue12823`, `issue13823`, and `pr12564`.
While some of the output looks worse to my eye, this behavior more
closely matches what I see when I open the PDFs in Adobe acrobat.
Fixes: #4706, #9713, #8245, #1344
Currently it's possible to accidentally, e.g. by simply copy-and-pasting from an existing test-case, add an unnecessary `"link": true`-entry for locally available PDF files.
This leads to inconsistencies in the manifest file, and doesn't feel like a great developer experience. However we can easily fix it by having `verifyManifestFiles` fail in this situation, and doing so actually turned up a couple of existing cases.