Holiday is over, now I have fun again. No code changes. (0.38.11)

docs/writing-tests.md

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+# Writing Tests
+
+How to author tests for Fun and its opcode implementations.
+
+## Test kinds
+- VM/opcode tests: exercise bytecode operations and VM behavior (target: `test_opcodes`).
+- Language/runtime tests: exercise user-visible features and stdlib behavior (target: `fun_test`).
+
+See `docs/testing.md` for how to build and run these targets with CTest.
+
+## Adding new tests
+The exact layout may evolve; generally:
+- Add new test sources alongside existing ones used by `fun_test`.
+- For opcode-focused tests, add cases where `test_opcodes` discovers them.
+
+Aim for:
+- Small, isolated test cases with clear assertions
+- One behavior per test; descriptive names
+- Minimal fixtures and setup
+
+## Guidelines
+- Prefer black-box testing via public APIs.
+- When adding features, include both positive and negative cases.
+- Keep tests deterministic; avoid non-deterministic timers or random sources unless seeded.