|author||Lei Zhang <firstname.lastname@example.org>||Tue Feb 08 22:12:14 2022 +0000|
|committer||Pdfium LUCI CQ <email@example.com>||Tue Feb 08 22:12:14 2022 +0000|
Add a minimal test case for an XFA document with a missing image. The image should render as a red square, but is currently missing. The test expectation is just the current state to make the test pass, since it is unclear what the pixel perfect expectation is. Bug: pdfium:1337 Change-Id: I01888f0b13b84eceb12a621b8e69ae14797963c6 Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/90370 Reviewed-by: Nigi <firstname.lastname@example.org> Commit-Queue: Lei Zhang <email@example.com>
PDFium uses the same build tooling as Chromium. See the platform-specific Chromium build instructions to get started, but replace Chromium's “Get the code” instructions with PDFium's.
The default architecture for Windows, Linux, and Mac is “
x64”. On Windows, “
x86” is also supported. GN parameter “
target_cpu = "x86"” can be used to override the default value. If you specify Android build, the default CPU architecture will be “
It is expected that there are still some places lurking in the code which will not function properly on big-endian architectures. Bugs and/or patches are welcome, however providing this support is not a priority at this time.
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mkdir repo cd repo gclient config --unmanaged https://pdfium.googlesource.com/pdfium.git gclient sync cd pdfium
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<directory> name is
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pdfium_test to build, one must set
pdf_is_standalone = true.
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ninja -C <directory> pdfium_all.
The pdfium_test program supports reading, parsing, and rasterizing the pages of a .pdf file to .ppm or .png output image files (Windows supports two other formats). For example:
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There are currently several test suites that can be run:
It is possible the tests in the
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If your change affects rendering, a pixel test should be added. Simply add a
testing/resources/pixel and the pixel runner will pick it up at the next run.
Make sure that your test case doesn't have any copyright issues. It should also be a minimal test case focusing on the bug that renders the same way in many PDF viewers. Try to avoid binary data in streams by using the
ASCIIHexDecode simply because it makes the PDF more readable in a text editor.
To try out your new test, you can call the
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To generate the expected image, you can use the
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Please make sure to have
optipng installed which optimized the file size of the resulting png.
.in files are PDF template files. PDF files contain many byte offsets that have to be kept correct or the file won't be valid. The template makes this easier by replacing the byte offsets with certain keywords.
This saves space and also allows an easy way to reduce the test case to the essentials as you can simply remove everything that is not necessary.
A simple example can be found here.
To transform this into a PDF, you can use the
$ ./testing/tools/fixup_pdf_template.py your_file.in
This will create a
your_file.pdf in the same directory as
There is no official style guide for the .in file, but a consistent style is preferred simply to help with readability. If possible, object numbers should be consecutive and
/SubType should be on top of a dictionary to make object identification easier.
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