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Test suite overview

The Walrus test suite is located in the tests/ directory and contains .walrus files that exercise various language features.
As of now, the testing suite is extremely incomplete and immature. Many language features lack dedicated tests, and existing tests may not cover all edge cases. There is no automatic test runner or framework in place yet - correctness is evaluated manually by inspecting output.

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Running tests

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Individual test files

You can run individual test files using the Walrus interpreter: 
cargo run --release -- tests/fibonacci.walrus -c

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Test file categories

The test files cover various language features:
  • Control flow - if/else, while loops, for loops, break/continue
  • Functions - Named functions, anonymous functions, closures, recursion
  • Data structures - Lists, dictionaries, tuples, ranges
  • Structs - Struct definitions, static methods
  • String manipulation - Slicing, indexing, format strings
  • Operators - Arithmetic, comparison, logical, short-circuit evaluation
  • Memory management - Garbage collection stress tests
  • Standard library - File I/O, system operations, math functions

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Manual validation

Currently, tests are validated by:
  1. Running the test file
  2. Inspecting the output
  3. Verifying expected behavior manually
1

Run the test

cargo run --release -- tests/example.walrus
2

Check the output

Verify the output matches expected results.
3

Test different execution modes

Run the same test in both interpreted and compiled modes to ensure consistency:
# Interpreted mode
cargo run -- tests/example.walrus -i

# Compiled mode (bytecode VM)
cargo run -- tests/example.walrus -c

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Comment support in tests

Walrus supports both single-line and multi-line comments in test files: Single-line comments: 
// This is a single-line comment
let x = 42; // Comment after code
Multi-line comments: 
/* This is a multi-line comment
   that spans multiple lines */
let y = 84; /* Inline multi-line comment */
Use comments to document test behavior and expected outcomes.

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Writing new tests

When adding new language features, create corresponding test files:
  1. Create a .walrus file in the tests/ directory
  2. Name it descriptively (e.g., string_slicing.walrus)
  3. Include comments explaining what is being tested
  4. Add test cases that cover edge cases
  5. Run the test to verify correct behavior
Example test structure: 
// Test: String slicing operations
// Expected: Various slice operations should work correctly

let text = "Hello, World!";

// Basic slice
let hello = text[0..5];
println(hello);  // Should print: Hello

// Slice to end
let world = text[7..];
println(world);  // Should print: World!

// Negative indices
let last = text[-1];
println(last);  // Should print: !

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Future improvements

Contributions to improve the test suite are highly encouraged:
  • Automatic test runner framework
  • Expected output validation
  • Test coverage reporting
  • Performance regression testing
  • Integration tests
  • Error handling tests
See Contributing for information on submitting improvements.

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