See briefcase and travertino

Issue

The tutorial contains code that does not work on the current release of colosseum.

Steps to Reproduce

1. Run pip install colosseum
2. Start Python interpreter
3. Run from colosseum.dimensions import Size, Box
4. Observe error message ModuleNotFoundError: No module named 'colosseum.dimensions'

The current release version of colosseum does not contains the dimensions module. See release history.

Related Screenshot

demo app making use of colosseum.

Can we compile the Rust AST generated from mozilla's CSS engine (in servo) into python so we can use it for Colosseum?

The Width-014 test for Colosseum creates a div of 1" height (which comes out to 96 px) by 1 px width, as seen here:

http://test.csswg.org/suites/css21_dev/nightly-unstable/html4/width-014.htm

The reference file for this test (colosseum/tests/web_platform/CSS2/normal_flow/ref/width-014.json) specifies it as 1.328125 px by 96 px.

This appears to be an incomplete reference file. The data file does return the correct value, but as the reference is incorrect, the test shows as failing.

...and in the event that I went about this all wrong and said something obvious or silly, do forgive me as I'm new and have no idea what I'm doing.

https://beekeeper.herokuapp.com/projects/pybee/colosseum

pytest gives a lot of flexibility for parametrized testing, and is becoming a defacto standard in Python testing. We should move the colosseum test suite to pytest.

Some values allow negative percentage values, but we are not checking those.

Extend the percent validator to include this extra check.

Issue

The following code, shown below, from this tutorial returns <Box (0x0 @ 0,0)> rather than what is expected: <Box (1000x1000 @ 0,0)>

Steps to Reproduce

Run the following lines of code as outlined in this tutorial:

>>> from colosseum import CSS
>>> node = MyDOMNode(style=CSS(width=1000, height=1000))
>>> layout = node.layout
>>> print(node.layout)

The response from print(node.layout) reveals that the width passed to the CSS object is not used by the resulting MyDOMNode object.

Please tag commit 6f9e93f for v0.1.6 and 5b33da6 for v0.1.5, so people can more easily find the version differences.

Thanks.

It feels like we should split the constants in a separate module just for that and the choices on another one.

This could lead to removing some circular imports and make the modules much more specific.

Describe the bug
The README points to the Technical reference but it is is essentially empty. It states "This is the technical reference for public APIs provided by Colosseum.".

To Reproduce
Steps to reproduce the behavior:

1. Go to the Technical reference.
2. See lack of content.

Expected behavior
A list of classes and functions.

Screenshots
If applicable, add screenshots to help explain your problem.

Environment:

• Software versions:
  • Browser: Firefox 9.3 (64-bit).

It looks like you can't add a node as a child of another node if the parent node has a display=BLOCK style.

from colosseum.constants import BLOCK
from colosseum.engine import layout
from colosseum import CSS
from tests.utils import TestNode, Display

root = TestNode(style=CSS(display=BLOCK), children=[TestNode()])
display = Display(dpi=96, width=1024, height=768)
layout(display, root)

Traceback (most recent call last):
File "test_box.py", line 25, in
layout(display, root)
File "/Users/mulka/Documents/Code/colosseum/colosseum/colosseum/engine.py", line 85, in layout
layout_box(display, node, containing_block, containing_block, font)
File "/Users/mulka/Documents/Code/colosseum/colosseum/colosseum/engine.py", line 234, in layout_box
calculate_height_and_margins(node, vertical)
File "/Users/mulka/Documents/Code/colosseum/colosseum/colosseum/engine.py", line 523, in calculate_height_and_margins
calculate_block_non_replaced_normal_flow_height(node, context)
File "/Users/mulka/Documents/Code/colosseum/colosseum/colosseum/engine.py", line 578, in calculate_block_non_replaced_normal_flow_height
content_height = last_child.layout.border_box_bottom
File "/Users/mulka/Documents/Code/colosseum/colosseum/colosseum/dimensions.py", line 393, in border_box_bottom
+ self.border_bottom_width
TypeError: unsupported operand type(s) for +: 'int' and 'NoneType'

After going through the how to contribute pages, and taking all the different steps I eventually get an error with the actual running of the test rather than a failed test. Is there any more documentation on where to look to fix these kinds of errors with tests?

This is my first time trying to contribute to open source, so if this is the wrong place to put this let me know, thanks for any help!

I think there should be a list of which CSS tests are higher priority to fix. Which ones are easy to fix? Which ones should we support? Which ones can wait?

The link to documentation in the changelog is broken:
https://github.com/beeware/colosseum/blob/master/CHANGELOG.rst