Generate page extraneous objects

[akarki2005]

Proposed Changes

This change fixes an issue which was causing extraneous nodes to appear in graphs on the generate page.

Before

Extraneous ellipses would appear on top of directed edges when hovering over a course to reveal its prerequisites.

After

These extraneous ellipses have been removed.

Type of Change

(Write an X or a brief description next to the type or types that best describe your changes.)

Type	Applies?
🚨 Breaking change (fix or feature that would cause existing functionality to change)
✨ New feature (non-breaking change that adds functionality)
🐛 Bug fix (non-breaking change that fixes an issue)	X
🎨 User interface change (change to user interface; provide screenshots)
♻️ Refactoring (internal change to codebase, without changing functionality)
🚦 Test update (change that only adds or modifies tests)
📦 Dependency update (change that updates a dependency)
🔧 Internal (change that only affects developers or continuous integration)

Checklist

(Complete each of the following items for your pull request. Indicate that you have completed an item by changing the [ ] into a [x] in the raw text, or by clicking on the checkbox in the rendered description on GitHub.)

Before opening your pull request:

• I have performed a self-review of my changes.
  • Check that all changed files included in this pull request are intentional changes.
  • Check that all changes are relevant to the purpose of this pull request, as described above.
• I have added tests for my changes, if applicable.
  • This is required for all bug fixes and new features.
• [N/A] I have updated the project documentation, if applicable.
  • This is required for new features.
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After opening your pull request:

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[coveralls]

Pull Request Test Coverage Report for Build dcca69fe-0286-465d-9841-42c195111577

Details

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+3.3%) to 54.096%

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Totals
Change from base Build c0eb9b7d-4eda-43fc-a7f8-d84bf4bcb0e2:	3.3%
Covered Lines:	2102
Relevant Lines:	3886

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💛 - Coveralls

[akarki2005]

Hi David, I've written up tests to ensure that my bug fix is working as intended; however, these tests only pass locally. In the CI run, they are failing with the below error message:

    GenerateControllerTests
      Generate Controller tests
        CSC148H1:                                                                                                                                                           FAIL
          Exception: Error running utility program: Unable to call the command  dot  with the arguments: " -Tsvg " because of:  dot: runInteractiveProcess: posix_spawnp: does not exist (No such file or directory)
          Use -p '/CSC148H1/' to rerun this test only.

I believe this issue stems from the fact that graphviz is not installed in the CI container, but I'm a bit apprehensive on just adding an install command to the CI config for it - was hoping for a second opinion. Thanks!

[david-yz-liu]

@akarki2005 nice work! I just left one minor comment, but overall the test approach is good. It's okay (and in fact, a good idea) to modify the CI configuration to install the system package for graphviz there.