http://github.com/norman/telescope/issues/issue/1

error_test.lua

require 'luarocks.require'
require 'telescope'

function raise_error() error("whoops") end
function do_not_raise_error() return true end

context("assert_error", function()
    test("with error being raised", function()
        assert_error(raise_error)
    end)

    test("with error not being raised", function()
        assert_error(do_not_raise_error)
    end)

    test("does not break the entire test suite", function()
        assert_error(raise_error)
    end)
end)

output.txt

^C------------------------------------------------------------------------
assert_error:
with error being raised                                              [P]
with error not being raised                                          [E]
does not break the entire test suite                                 [P]
------------------------------------------------------------------------
3 tests 2 passed 3 assertions 0 failed 1 error 0 unassertive 0 pending

with error not being raised:
...e/.luarocks/rocks//telescope/scm-1/lua/telescope.lua:147: interrupted!
stack traceback:
        ...e/.luarocks/rocks//telescope/scm-1/lua/telescope.lua:374: in function 'invoke_test'
        ...e/.luarocks/rocks//telescope/scm-1/lua/telescope.lua:399: in function 'run'
        ...ome/adaniele/.luarocks/rocks/telescope/scm-1/bin/tsc:266: in main chunk
        [C]: ?