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Assert

Must be included via require.

assert.isnil​

Asserts that value is nil

Parameters​

  1. value — The value which should be nil.

Errors​

An assertion error is thrown if the value is not nil.

pluto
local assert = require("assert")
assert.isnil(nil) -- Passes.
assert.isnil(5) -- Error:
--[[
test.pluto:4 -> Assertion Error: (assert.isnil)
    Intended Value: nil
    Received Value: 5
stack traceback:
    [C]: in function 'error'
    [string "pluto:assert"]:75: in function <[string "pluto:assert"]:46>
    (...tail calls...)
    [C]: in ?
--]]

assert.istrue​

Asserts that value is true.

Parameters​

  1. value — The value which should be true.

Errors​

An assertion error is thrown if value is not true

pluto
local assert = require("assert")
assert.istrue(true) -- Passes.
assert.istrue(false) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.istrue)
    Intended Value: true
    Received Value: false
stack traceback:
    [C]: in function 'error'
    [string "pluto:assert"]:75: in function <[string "pluto:assert"]:46>
    (...tail calls...)
    test.pluto:4: in main chunk
    [C]: in ?
--]]

assert.isfalse​

Asserts that value is false.

Parameters​

  1. value — The value which should be false.

Errors​

An assertion error is thrown if value is not false.

pluto
local assert = require("assert")
assert.isfalse(false) -- Passes.
assert.isfalse(true) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.isfalse)
    Intended Value: false
    Received Value: true
stack traceback:
    [C]: in function 'error'
    [string "pluto:assert"]:75: in function <[string "pluto:assert"]:46>
    (...tail calls...)
    test.pluto:4: in main chunk
    [C]: in ?
--]]

assert.falsy​

Asserts that value is a "falsy" value. Falsy means the value is nil or false.

Parameters​

  1. value — The value which should be falsy.

Errors​

An assertion error is thrown if value is not falsy.

pluto
local assert = require("assert")
assert.falsy(nil) -- Passes.
assert.falsy(false) -- Passes.
assert.falsy("Hello, world!") -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.falsy)
    Intended Value: nil or false
    Received Value: string(13) "Hello, world!"
stack traceback:
    [C]: in function 'error'
    [string "pluto:assert"]:75: in function <[string "pluto:assert"]:46>
    (...tail calls...)
    test.pluto:4: in main chunk
    [C]: in ?
--]]

assert.truthy​

Asserts that value is a "truthy" value. This is the inverse of "falsy", a.k.a, any value that isn't nil or false is truthy.

Parameters​

  1. value — The value which should be truthy, a.k.a it should not be nil or false.

Errors​

An assertion error is thrown if value is not truthy, i.e if value is nil or false.

pluto
local assert = require("assert")
assert.truthy("Hello, world!") -- Passes.
assert.truthy(nil) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.truthy)
    Intended Value: not nil or false
    Received Value: nil
stack traceback:
    [C]: in function 'error'
    [string "pluto:assert"]:75: in function <[string "pluto:assert"]:46>
    (...tail calls...)
    test.pluto:4: in main chunk
    [C]: in ?
--]]

assert.notnil​

Asserts that value is not nil.

Parameters​

  1. value — The value which should not be nil.

Errors​

An assertion error is thrown if value is nil.

pluto
local assert = require("assert")
assert.notnil("Hello, world!") -- Passes.
assert.notnil(nil) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.notnil)
    Intended Value: not nil
    Received Value: nil
stack traceback:
    [C]: in function 'error'
    [string "pluto:assert"]:75: in function <[string "pluto:assert"]:46>
    (...tail calls...)
    test.pluto:4: in main chunk
    [C]: in ?
--]]

assert.equal​

Asserts that value1 is equal to value2.

This function can compare tables, looking at both the table's reference and what's inside it. If the tables aren't exactly the same (meaning they don't reference the same table), the function will go through the contents of the tables and compare them step by step.

Parameters​

  1. value1 — The first value.
  2. value2 — The second value.

Errors​

An assertion error is thrown if value1 does not equal value2.

pluto
local assert = require("assert")
assert.equal("Hello, world!", "Hello, world...") -- Error:
--[[
pluto: test.pluto:3 -> Assertion Error: (assert.equal)
    Intended Value: string(13) "Hello, world!"
    Received Value: string(15) "Hello, world..."
--]]
assert.equal("Hi there.":split(" "), "Hello there.":split(" ")) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.equal)
    Intended Value: { [1] = string(2) "Hi", [2] = string(6) "there.", }
    Received Value: { [1] = string(5) "Hello", [2] = string(6) "there.", }
--]]

assert.nequal​

Asserts that value1 is not equal to value2.

This function can compare tables, looking at both the table's reference and what's inside it. If the tables aren't exactly the same (meaning they don't reference the same table), the function will go through the contents of the tables and compare them step by step.

Parameters​

  1. value1 — The first value.
  2. value2 — The second value.

Errors​

An assertion error is thrown of value1 does equal value2.

pluto
local assert = require("assert")
assert.nequal("Hello, world!", "Hi, world!") -- Passes.
assert.nequal("Hi there.":split(" "), "Hello there.":split(" ")) -- Passes.

assert.less​

Asserts that value1 is less than value2.

Parameters​

  1. value1 — The first number.
  2. value2 — The second number.

Errors​

An assertion error is thrown if value1 is not less than value2.

pluto
local assert = require("assert")
assert.less(1, 2) -- Passes.
assert.less(1, 1) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.less)
    Expression: (1 < 1) == false
--]]

assert.lesseq​

Asserts that value1 is less than or equal to value2.

Parameters​

  1. value1 — The first number.
  2. value2 — The second number.

Errors​

An assertion error is thrown if value1 is not less than or equal to value2.

pluto
local assert = require("assert")
assert.lesseq(1, 2) -- Passes.
assert.lesseq(1, 0) -- Error:
--[[
pluto: test.pluto:3 -> Assertion Error: (assert.lesseq)
    Expression: (1 <= 0) == false
--]]

assert.greater​

Asserts that value1 is greater than value2.

Parameters​

  1. value1 — The first number.
  2. value2 — The second number.

Errors​

An assertion errros is thrown if value1 is not greater than value2.

pluto
local assert = require("assert")
assert.greater(3, 2) -- Passes.
assert.greater(3, 3) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.greater)
    Expression: (3 > 3) == false
--]]

assert.greatereq​

Asserts that value1 is greater than or equal to value2.

Parameters​

  1. value1 — The first number.
  2. value2 — The second number.

Errors​

An assertion errros is thrown if value1 is not greater than or equal to value2.

pluto
local assert = require("assert")
assert.greatereq(3, 2) -- Passes.
assert.greatereq(3, 3) -- Passes.

assert.noerror​

Asserts that callback does not raise an error when called.

Parameters​

  1. callback — A function reference.
  2. ... — Any other parameters passed to this function will be passed to the callback.

Errors​

An assertion error is thrown if callback raises an error.

pluto
local assert = require("assert")
assert.noerror(tostring, 400) -- Passes.
assert.noerror(error, "argument argument") -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.noerror)
    An error was raised: argument argument
--]]

assert.haserror​

Asserts that callback does raise an error when called.

Parameters​

  1. callback — A function reference.
  2. ... — Any other parameters passed to this function will be passed to the callback.

Errors​

An assertion error is thrown if callback does not raise an error.

pluto
local assert = require("assert")
assert.haserror(error, "argument argument") -- Passes.
assert.haserror(tostring, 400) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.haserror)
    Expected an error, but there was none.
--]]

assert.searcherror​

Asserts that callback raises an error, and that substring is present within the error message.

Parameters​

  1. substring — The substring that should be inside of the error message.
  2. callback — A function reference.
  3. ... — Any other parameters passed to this function will be passed to the callback.

Errors​

An assertion error is thrown if:

  1. callback does not raise an error.
  2. callback does raise an error, but the error message does not contain substring.
pluto
local assert = require("assert")
assert.searcherror("argument", error, "argument argument") -- Passes.
assert.searcherror("something", tostring, 400) -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.searcherror)
    Expected an error, but there was none.
--]]
assert.searcherror("argument", error, "argument argument") -- Passes.
assert.searcherror("argument", error, "something something") -- Error:
--[[
pluto: test.pluto:4 -> Assertion Error: (assert.searcherror)
    Absent String: argument
    Error Message: something s
--]]

assert.contains​

Asserts that element is contained inside of container by using Pluto's modified in operator. It's important to understand the type constraints of in to understand the type constraints here.

Parameters​

  1. element — The element to search for. If container is a string, element must be a string. If container is a table, element can be any type.
  2. container — The container that element should be inside of. The container should be a string or table.

Errors​

An assertion error is thrown if:

  1. element is not contained inside of container.
  2. element or container are of the wrong type and cannot be used with Pluto's modified in operator. 
pluto
assert.contains("hello", { "hello", "world" }) -- Passes.
assert.contains("world", { "hello", "hello" }) -- Fails.