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Elixir / Files Data and Testing

ExUnit tests

Learn ExUnit tests in Elixir through a focused explanation, a dedicated topic-specific example, an engineering boundary, and a mastery check.

12 min read • Advanced

ExUnit tests is a focused Elixir lesson inside Files Data and Testing. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through ExUnit tests and identify the behavior that would change if that construct were removed or replaced. Pay attention to the language-specific rules shown by the syntax, because neighboring lessons intentionally exercise different mechanisms.

Topic-specific example

elixir-0078-800457d95b.exs
elixir Try It Live 
values = [79, 80, 81]
IO.inspect(Enum.sum(values)) # ExUnit tests
Edge case / engineering note

For ExUnit tests, test one realistic boundary: empty data, invalid input, unavailable resources, lifetime/cleanup, type constraints, or concurrency timing where applicable. A successful happy path is not enough to prove the construct is used correctly.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

ExUnit tests Mastery Check →
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Doctests