Testing

VHP uses .vhpt files (inspired by PHP’s .phpt format) for testing.

Test File Format

Basic Test

--TEST--
Addition operator
--FILE--
<?php
echo 2 + 3;
--EXPECT--
5

Error Test

--TEST--
Division by zero
--FILE--
<?php
echo 10 / 0;
--EXPECT_ERROR--
Division by zero

Test Sections

Section Required Description
--TEST-- Yes Test name (displayed in output)
--FILE-- Yes PHP code to execute
--EXPECT-- Yes* Expected output (exact match)
--EXPECT_ERROR-- Yes* Expected error substring
--DESCRIPTION-- No Detailed description
--SKIPIF-- No Reason to skip (for unimplemented features)

*One of --EXPECT-- or --EXPECT_ERROR-- is required.

Running Tests

# Run all tests (compact output)
vhp test

# Verbose output (shows each test name)
vhp test -v

# Run tests from a custom directory
vhp test mydir

# Run a single test file
vhp test path/to/test.vhpt

Example Output

$ vhp test -v

Running 120 tests...
  PASS Addition operator
  PASS Basic if statement
  PASS For loop with break
  PASS User-defined function
  PASS Built-in strlen
  PASS String concatenation
  SKIP Array literals (Arrays not yet implemented)
  ...

Tests: 120 total, 119 passed, 0 failed, 0 errors, 1 skipped

Test Organization

Tests are organized by feature in the tests/ directory:

tests/
├── builtins/       # Built-in function tests
├── comments/       # Comment syntax tests
├── control_flow/   # Control flow tests (if, while, for, switch)
├── echo/           # Echo statement tests
├── errors/         # Error handling tests
├── expressions/    # Expression evaluation tests
├── functions/      # User-defined function tests
├── html/           # HTML passthrough tests
├── numbers/        # Numeric literal tests
├── operators/      # Operator tests
├── strings/        # String literal tests
├── tags/           # PHP tag tests
└── variables/      # Variable tests

Writing Tests

Best Practices

  1. One concept per test - Test a single feature or behavior
  2. Descriptive names - The --TEST-- section should clearly describe what’s being tested
  3. Minimal code - Keep the --FILE-- section as short as possible
  4. Exact expectations - The --EXPECT-- section must match output exactly (including whitespace)

Example: Testing a New Feature

When adding a new feature, create corresponding tests:

--TEST--
New feature: basic usage
--FILE--
<?php
// Test the basic case
--EXPECT--
expected output

--TEST--
New feature: edge case
--FILE--
<?php
// Test an edge case
--EXPECT--
expected output

--TEST--
New feature: error handling
--FILE--
<?php
// Test error case
--EXPECT_ERROR--
expected error message

Skipping Tests

Use --SKIPIF-- for features not yet implemented:

--TEST--
Array push function
--SKIPIF--
Arrays not yet implemented
--FILE--
<?php
$arr = [1, 2, 3];
array_push($arr, 4);
echo count($arr);
--EXPECT--
4

Skipped tests appear in the summary but don’t cause failures.