testthat: Unit Testing for R

produces useful output

Test passed 
-- Failure ('reporters/tests.R:12:3'): Failure:1 -------------------------------
FALSE is not TRUE

`actual`:   FALSE
`expected`: TRUE

-- Failure ('reporters/tests.R:16:8'): Failure:2a ------------------------------
FALSE is not TRUE

`actual`:   FALSE
`expected`: TRUE 
Backtrace:
    x
 1. \-f()
 2.   \-testthat::expect_true(FALSE)

-- Error ('reporters/tests.R:23:3'): Error:1 -----------------------------------
Error in `eval(code, test_env)`: stop

-- Error ('reporters/tests.R:29:8'): errors get tracebacks ---------------------
Error in `h()`: !
Backtrace:
    x
 1. \-f()
 2.   \-g()
 3.     \-h()

-- Skip ('reporters/tests.R:37:3'): explicit skips are reported ----------------
Reason: skip

-- Skip ('reporters/tests.R:40:1'): empty tests are implicitly skipped ---------
Reason: empty test

-- Warning ('reporters/tests.R:47:5'): warnings get backtraces -----------------
def
Backtrace:
    x
 1. \-f()

-- Skip ('reporters/tests.R:45:1'): warnings get backtraces --------------------
Reason: empty test