Two-fer
or 2-fer
is short for two for one. One for you and one for me.
"One for X, one for me."
When X is a name or "you".
If the given name is "Alice", the result should be "One for Alice, one for me." If no name is given, the result should be "One for you, one for me."
Execute the tests with:
$ mix test
In the test suites, all but the first test have been skipped.
Once you get a test passing, you can unskip the next one by
commenting out the relevant @tag :pending
with a #
symbol.
For example:
# @tag :pending
test "shouting" do
assert Bob.hey("WATCH OUT!") == "Whoa, chill out!"
end
Or, you can enable all the tests by commenting out the
ExUnit.configure
line in the test suite.
# ExUnit.configure exclude: :pending, trace: true
If you're stuck on something, it may help to look at some of the available resources out there where answers might be found.
https://en.wikipedia.org/wiki/Two-fer
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
ExUnit.start()
ExUnit.configure(exclude: :pending, trace: true)
defmodule TwoFerTest do
use ExUnit.Case
test "no name given" do
assert TwoFer.two_fer() == "One for you, one for me"
end
@tag :pending
test "a name given" do
assert TwoFer.two_fer("Gilberto Barros") == "One for Gilberto Barros, one for me"
end
@tag :pending
test "when the parameter is a number" do
assert_raise FunctionClauseError, fn ->
TwoFer.two_fer(10)
end
end
@tag :pending
test "when the parameter is an atom" do
assert_raise FunctionClauseError, fn ->
TwoFer.two_fer(:bob)
end
end
@tag :pending
test "when the parameter is a charlist" do
assert_raise FunctionClauseError, fn ->
refute TwoFer.two_fer('Jon Snow')
end
end
end
defmodule TwoFer do
@spec two_fer(String.t()) :: String.t()
def two_fer(name \\ "you")
def two_fer(name) when is_binary(name), do: "One for #{name}, one for me"
def two_fer(_), do: raise FunctionClauseError
end
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