```
# NOT RUN {
add_one <- function(x) x + 1
expect_equal(add_one(2), 3)
with_mock(
add_one = function(x) x - 1,
expect_equal(add_one(2), 1)
)
square_add_one <- function(x) add_one(x)^2
expect_equal(square_add_one(2), 9)
expect_equal(
with_mock(
add_one = function(x) x - 1,
square_add_one(2)
),
1
)
# local_mock() -------------------------------
plus <- function(x, y) x + y
test_that("plus(1, 1) == 2", {
expect_equal(plus(1, 1), 2)
})
test_that("plus(1, 1) == 3", {
local_mock(plus = function(x, y) 3)
expect_equal(plus(1, 1), 3)
})
# }
```

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