Data providers

bashunit offers a way to parameterize your test functions with data providers Ideal when the test function needs to accept a single or multiple argument.

---

You can add a special comment before a test function to specify an auxiliary function. This function controls how many times the test will run and what arguments it will receive.

Each run is treated as a separate test, so it can pass or fail independently. Plus, set_up and tear_down are called before and after each run. This reduces code repetition and helps create related tests more efficiently.

---

A data provider function is specified as follows:

Note: The previous # data_provider syntax is still supported but deprecated. Prefer using the @ prefix going forward.

Example

# @data_provider provider_function_name
function test_my_test_case() {
  ...
}

The provider function can echo a single value like "one" or multiple values "one" "two" "three".

Interpolating arguments in test names

You can reference the values provided by a data provider directly in the test function name using placeholders like ::1::, ::2::, ... matching the argument position.

example_test.sh

# @data_provider fizz_numbers
function test_returns_fizz_when_multiple_of_::1::_like_::2::_given() {
  # ...
}

function fizz_numbers() {
  echo 3 4
  echo 3 6
}

Output

Running example_test.sh
✓ Passed: Returns fizz when multiple of '3' like '4' given
✓ Passed: Returns fizz when multiple of '3' like '6' given

Multiple args in one call

example_test.sh

# @data_provider provider_directories
function test_directories_exists() {
  local dir1=$1
  local dir2=$2
  local dir3=$3

  assert_directory_exists "$dir1"
  assert_directory_exists "$dir2"
  assert_directory_exists "$dir3"
}

function provider_directories() {
  echo "/usr" "/etc" "/var"
}

Output

Running example_test.sh
✓ Passed: Directories exists (/usr /etc /var)

Single arg in multiple calls

example_test.sh

# @data_provider provider_directories
function test_directory_exists() {
  local directory=$1

  assert_directory_exists "$directory"
}

function provider_directories() {
  echo "/usr"
  echo "/etc"
  echo "/var"
}

Output

Running example_test.sh
✓ Passed: Directory exists (/usr)
✓ Passed: Directory exists (/etc)
✓ Passed: Directory exists (/var)

Multiple args in multiple calls

example_test.sh

# @data_provider provider_directories
function test_directory_exists() {
  local outro=$1
  local directory=$2

  assert_equals "outro" "$outro"
  assert_directory_exists "$directory"
}

function provider_directories() {
  echo "outro" "/usr"
  echo "outro" "/etc"
  echo "outro" "/var"
}

Output

Running example_test.sh
✓ Passed: Directory exists (outro /usr)
✓ Passed: Directory exists (outro /etc)
✓ Passed: Directory exists (outro /var)