Fix: Jupyter notebook LaTeX math tests

[b0ink]

Description

This fixes and improves the tests used in test_ipynb_to_pdf to confirm valid PDF rendering of LaTeX math in jupyter notebooks. The pdf-reader incorrectly parses a valid render of the inline math as BMI: bmi = weigh2 instead of weight.

I extended the LaTeX to ensure full words like weight and height are parsed correctly, though (kg) is still incorrectly parsed as (2g) (see below). Now, tests confirm a valid PDF render by checking for weight and height without needing to check for newlines or other notation.

I also used text{hei}text{ght} to separate the words to guarantee a reliable unit test pass if the words are detected. Below is a before/after of the inline LaTeX, the PDF render, and the output of pdf-reader.

Before

Inline math LaTeX:

$\text{bmi}=\frac{\text{weight}}{\text{height}^2}$

PDF Render

pdf-reader output

BMI: bmi =		weigh2
				height

After

Inline math LaTeX:

$\text{bmi}=\frac{\text{weig}\text{ht (kg)}}{\text{hei} \text{ght (m)}^2}$

PDF Render

pdf-reader output

BMI: bmi =		weight (2g)
				height (m)

Tests used to confirm math latex rendered correctly

assert reader.pages.last.text.include?("BMI: bmi =")
assert reader.pages.last.text.include?("weight")
assert reader.pages.last.text.include?("height (m)")

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

rake test

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation if appropriate
• My changes generate no new warnings
• I have created or extended unit tests to address my new additions
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[b0ink]

doubtfire-lms#444