[colinleach]

They are getting a bit more complicated by this stage, with some serious Julia-only testing to think about. I'm happy to keep the ::Integer restriction in difference-of-squares. rational-numbers has always been near-impossibly difficult, so I've moved the most challenging bits behind an opt-in flag. I think this may need an instructions-append.md, so I'll mark this draft for now.

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Adds Jinja2 test templates for difference-of-squares, complex-numbers, rational-numbers, custom-set, circular-buffer and robot-simulator

Each runtests.jl is regenerated from canonical data, and every exercise passes against its example solution, including the opt-in bonus tests. Every templated exercise still passes generate_tests.py --check. No shared macros changed in this PR.

The canonical-only rule applies, with two kinds of exception, both worth a look:

• difference-of-squares keeps the ::Integer type assertions.
• Opt-in bonus tests are kept behind their flags. circular-buffer and complex-numbers already had them. rational-numbers now has one too.

The bonus blocks are Julia code, not cases, so they are written into the template as a fixed block after the canonical cases rather than in .meta/additional_tests.json. The test file checks the flag with @isdefined(...). Each example solution sets its flag, so CI runs the bonus tests.

Hand-written tests that weren't canonical, and weren't behind a flag, have been removed.

Things to look at:

• difference-of-squares:
  • Every assertion keeps the type check, e.g. @test square_of_sum(5)::Integer == 225, so solutions that use / instead of ÷ still fail.
  • 13 assertions became 9. The canonical inputs are 1, 5 and 100 for each function. Removed: the three 10 cases and difference(0).
• complex-numbers:
  • Canonical expressions become Julia: "pi" → π, "e" → ℯ, "ln(2)/2" → log(2)/2.
  • Division and exp compare with ≈. exp keeps atol = 1e-15. The two exact divisions that used == now also use ≈.
  • "Imaginary unit" is the canonical ComplexNumber(0, 1) * ComplexNumber(0, 1) instead of ComplexNumber(0, 1)^2.
  • Bonus A (operations between real and complex numbers) is canonical, so it is generated, behind enable_realcomplex_tests as before.
  • Bonus B (jm syntax sugar) is not canonical. It is copied unchanged into the template, behind enable_syntaxsugar_tests.
  • Removed: @test ComplexNumber <: Number.
• rational-numbers:
  • New enable_bonus_tests flag. The old file's Julia-specific tests are now opt-in, in a "Bonus: Julia number interfaces" testset. These are:
    • RationalNumber <: Real
    • RationalNumber(0, 0) throws ArgumentError
    • conversion and promotion, with the comment pointing to the manual
    • zero / one
    • adding a RationalNumber and an integer, in both orders
    • the "Ordering" loop based on Julia Base's tests (MIT, credited as before)
  • The stub has an "uncomment to enable" comment for the flag, as complex-numbers does. .meta/example.jl ends with enable_bonus_tests = true.
  • Without the flag, students only need the canonical operations between two RationalNumbers. Adding an integer moved into the bonus, because it depends on promotion.
  • The canonical cases include two the old file didn't have: abs(RationalNumber(-1, -2)) and RationalNumber(-3, 5)^-2.
  • Reduction cases keep the numerator(r) / denominator(r) checks.
  • The real-to-rational power 8^RationalNumber(4, 3) is compared with ≈ 16.0, the canonical value. Before, it was compared with ≈ 15.999999999999998.
• circular-buffer:
  • Each canonical operation becomes a statement in order:
    • write: @test push!(cb, x) === cb
    • overwrite: push!(cb, x; overwrite=true)
    • read: @test popfirst!(cb) == x
    • clear: @test empty!(cb) === cb
    • Operations that should fail are @test_throws BoundsError.
  • The bonus block (<: AbstractVector and the DataStructures.jl test set) is copied unchanged into the template, behind enable_bonus_tests. It matches the "Bonus tasks" section of instructions.append.md.
  • Removed, because they weren't behind the flag: the "overwrite=true and overwrite=false" and "type parameter" testsets.
• custom-set:
  • The canonical intersection, difference and union cases each test both the plain function and its in-place version (intersect / intersect!, complement / complement!, union / union!), as before. These used to be in separate "in-place" and "not in-place" testsets.
  • Empty results are checked with isempty(...).
  • Removed: CustomSet <: Base.AbstractSet, and the length, iteration and copy tests.
• robot-simulator:
  • Every canonical case builds Robot((x, y), DIRECTION), runs move!(r, "...") for move cases, then checks position(r) == Point(x, y) and heading(r) == DIRECTION.
  • The rotation and advance cases are now one testset each, run through move! with "R", "L" or "A". 31 assertions became 36.
  • Removed: "mutating functions should return robot", and the direct calls to turn_right!, turn_left! and advance!. Solutions still need these functions to implement move!, but no test calls them directly.

[github-actions]

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[colinleach]

I've added a brief instructions append to rational numbers, and a fairly minimal set of function stubs in the solution file. I still don't get an entirely warm fuzzy feeling about it, but it's probably OK for something with difficulty 8.

[colinleach]

I spotted belatedly that robot-simulator has no function stubs. That is fixed in #1167 (and much else besides).

[depial]

Just the one comment, but I think the rest is okay.

[exercism-i18n]

This PR has been translated 🚀