There's built-in ESLint rule, see `sort-imports`, to ensure that all `import`-statements are sorted alphabetically, since that often helps with readability.
Unfortunately there's no corresponding rule to sort `export`-statements alphabetically, however there's an ESLint plugin which does this; please see https://www.npmjs.com/package/eslint-plugin-sort-exports
The only downside here is that it's not automatically fixable, but the re-ordering is a one-time "cost" and the plugin will help maintain a *consistent* ordering of `export`-statements in the future.
*Note:* To reduce the possibility of introducing any errors here, the re-ordering was done by simply selecting the relevant lines and then using the built-in sort-functionality of my editor.
Given that the API will now, after PR 12039, automatically pick the correct factories to use depending on the environment (browser vs. Node.js), we can utilize that in the unit-tests as well. This way we don't have to manually repeat the same initialization code in *multiple* unit-tests.
*Note:* The *official* PDF.js API is defined in `src/pdf.js`, hence the new exports in `src/display/api.js` will not affect that.
Also, updates the unit-test `FileReaderFactory` helpers similarily.
*Drive-by change:* Fix the `CMapReaderFactory` usage in the annotation unit-tests, since the cache should only contain raw data and not a Promise. While this obviously works as-is, having unit-tests that "abuse" the intended data format can easily lead to unnecessary failures if changes are made to the relevant `src/core/` code.
The last unit-test didn't work correctly, since an error was thrown in `PDFDocument._hasOnlyDocumentSignatures` because the mocked `XRef`-instance wasn't actually being set correctly.
Also, updates the `XRefMock` to use `async` methods where appropriate.
Note how the `getFontID`-method in `src/core/fonts.js` is *completely* global, rather than properly tied to the current document. This means that if you repeatedly open and parse/render, and then close, even the *same* PDF document the `fontID`s will still be incremented continuously.
For comparison the `createObjId` method, on `idFactory`, will always create a *consistent* id, assuming of course that the document and its pages are parsed/rendered in the same order.
In order to address this inconsistency, it thus seems reasonable to add a new `createFontId` method on the `idFactory` and use that when obtaining `fontID`s. (When the current `getFontID` method was added the `idFactory` didn't actually exist yet, which explains why the code looks the way it does.)
*Please note:* Since the document id is (still) part of the `loadedName`, it's thus not possible for different documents to have identical font names.
This moves, and slightly simplifies, code that's currently residing in the unit-test utils into the actual library, such that it's bundled with `GENERIC`-builds and used in e.g. the API-code.
As an added bonus, this also brings out-of-the-box support for CMaps in e.g. the Node.js examples.
Since this helper function is no longer used anywhere in the main code-base, but only in a couple of unit-tests, it's thus being moved to a more appropriate spot.
Finally, the implementation of `isEmptyObj` is also tweaked slightly by removing the manual loop.
Please find additional details about the ESLint rule at https://eslint.org/docs/rules/prefer-const
With the recent introduction of Prettier this sort of mass enabling of ESLint rules becomes a lot easier, since the code will be automatically reformatted as necessary to account for e.g. changed line lengths.
Note that this patch is generated automatically, by using the ESLint `--fix` argument, and will thus require some additional clean-up (which is done separately).
In order to eventually get rid of SystemJS and start using native `import`s instead, we'll need to provide "complete" file identifiers since otherwise there'll be MIME type errors when attempting to use `import`.
Note that Prettier, purposely, has only limited [configuration options](https://prettier.io/docs/en/options.html). The configuration file is based on [the one in `mozilla central`](https://searchfox.org/mozilla-central/source/.prettierrc) with just a few additions (to avoid future breakage if the defaults ever changes).
Prettier is being used for a couple of reasons:
- To be consistent with `mozilla-central`, where Prettier is already in use across the tree.
- To ensure a *consistent* coding style everywhere, which is automatically enforced during linting (since Prettier is used as an ESLint plugin). This thus ends "all" formatting disussions once and for all, removing the need for review comments on most stylistic matters.
Many ESLint options are now redundant, and I've tried my best to remove all the now unnecessary options (but I may have missed some).
Note also that since Prettier considers the `printWidth` option as a guide, rather than a hard rule, this patch resorts to a small hack in the ESLint config to ensure that *comments* won't become too long.
*Please note:* This patch is generated automatically, by appending the `--fix` argument to the ESLint call used in the `gulp lint` task. It will thus require some additional clean-up, which will be done in a *separate* commit.
(On a more personal note, I'll readily admit that some of the changes Prettier makes are *extremely* ugly. However, in the name of consistency we'll probably have to live with that.)
This way we can avoid manually building a "document id" in multiple places in `evaluator.js`, and it also let's us avoid passing in an otherwise unnecessary `PDFManager` instance when creating a `PartialEvaluator`.
This allows simplification of the 'creates pdf doc from URL and aborts loading after worker initialized' API unit-test.
Note that the `DOMFileReaderFactory` uses the Fetch API, for simplicity, since it should be available in all browsers where we're running tests.
These were removed in PR 9170, since they were unused in the browsers that we'll support in PDF.js version `2.0`.
However looking at the output of Travis, where a subset of the unit-tests are run using Node.js, there's warnings about `btoa` being undefined. This doesn't appear to cause any errors, which probably explains why we didn't notice this before (despite PR 9201).
I really cannot understand why this change is necessary, since modern browsers such as Firefox and Chrome work just fine with the old code.
Hence this is patch is yet another "hack" that's needed just because IE apparently cannot just work like you'd expect.
For consistency, the Node factory used in the CMap unit-tests is changed as well.
Fixes 8193.