Video Game Design and Coding

PLECK lesson 155 · suggested week 31, day 5

Run the core production regression

Objective. Prove the minimum loop before deeper-system work.

Godot Engine Standard desktop editor 4.7.2-stable, GDScript (Godot 4), Compatibility renderer. Headless Godot 4.7.2.stable.official.ed1daf0bf passed 106 assertions on the supplied scaffolds, including malformed JSON saves. Audio used the Dummy driver and a synthetic WAV, not a speaker. The visual editor, browser export, and signed-in submission were not tested. The desk still does not run a student's own upload.

About 55 minutes. The due date is chosen by a parent.

Input robustness, rule completion, challenge and progress

Suggested pace: Recall and predict 5 min; Read instruction and scaffold 12 min; Build or design the assigned artifact 25 min; Run acceptance tests 8 min; Explain and checkpoint 5 min.

Materials: Godot Standard 4.7.2 desktop editor (GDScript, Compatibility renderer), Local course folder and prior checkpoint, No paid assets or public account required.

Comes after VGC-L154.

Freeze the core for one session and run launch, input, rule, challenge, progress, ending and replay tests from a restored artifact. Record pass/fail, actual behavior and issue ID. Fix the most serious reproducible defect, then rerun its test and adjacent tests. Do not add art or a second room while a required loop is broken. A clean core checkpoint is a recovery point for the next phase, where the richer system and content add complexity.

Worked example

A repeat-input test might press a one-time choice rapidly. The accepted event happens once, while later calls observe the changed state and do nothing. Scaffold C-TESTS — A tiny pure-function test harness Setup: Attach to Node TestLab. If using command line, create a separate SceneTree harness rather than running this Node script with --script. Run current TestLab scene in editor; assert reports a failed condition in Debugger. No external test framework or package is needed. ```gdscript extends Node func bounded_score(old_score: int, change: int) -> int: return clampi(old_score + change, 0, 999) func _ready() -> void: assert(bounded_score(10, 2) == 12) assert(bounded_score(0, -3) == 0) assert(bounded_score(998, 9) == 999) print("3 score checks passed") ```

A tiny pure-function test harness

GDScript (Godot 4, not Scratch, Python, JavaScript or C#). Scaffold C-TESTS. Copy starts from this text. The desk does not run it.

Scene and node setup

Attach to Node TestLab. If using command line, create a separate SceneTree harness rather than running this Node script with --script. Run current TestLab scene in editor; assert reports a failed condition in Debugger. No external test framework or package is needed.

extends Node
func bounded_score(old_score: int, change: int) -> int:
    return clampi(old_score + change, 0, 999)
func _ready() -> void:
    assert(bounded_score(10, 2) == 12)
    assert(bounded_score(0, -3) == 0)
    assert(bounded_score(998, 9) == 999)
    print("3 score checks passed")

Checks to run in the editor

  • All three assertions pass.
  • Intentionally change expected 12 to 13 and observe a failure, then restore.

Native Godot 4.7.2.stable.official.ed1daf0bf headless compile and representative node-tree/runtime tests passed; see native-qa-results.json. Visual UI, audible output, exports and website submission still need separate checks.

Run the core production regression — evidence task

  1. 1. Run the seven core acceptance tests from restored source.
  2. 2. Repair one failing issue or demonstrate a controlled fault repair in a duplicate.

Deliverable. Core-production source checkpoint and regression report.

Acceptance checks

  • VGC-L155-T1. Every pass has an actual result.
  • VGC-L155-T2. The repaired case and neighboring features are retested.

Understanding question. Why test from a restored artifact rather than only the open editor project?

Include a downloadable project ZIP with project.godot, .tscn, .gd and original asset files when code changes. A private, teacher-accessible download link to that ZIP is equivalent. Screenshots or a playthrough do not replace editable source.

If this is still shaky. Work on one task-board item at a time and checkpoint after each passing test. Do not expand the room count yet. Start with the first assigned task and re-run its acceptance test before adding the remaining feature.

Optional extra. Add a harmless alternate input or optional route after required mechanics pass. Document one changed parameter, your prediction, and the observed effect; optional, not required for completion.

Turn in typed notes and a JPEG, PNG, or WebP screenshot. One https address is stored as text and is not opened, extracted, or run. An MP3, WAV, M4A, MP4, or WebM file up to 4 MB can show a demo. The demo does not replace editable source. Zip and code files are refused. If there is no private link, keep the project on the family computer and review the code in person.

  • Your first 2D game

    Free public tutorial; no account; external asset download is optional, not used by this course.

    · Opening this link does not submit the lesson.

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