R: Capture conditions, including messeages, warnings,...

capture_condition {testthat} | R Documentation

## Capture conditions, including messeages, warnings, expectations, and errors.

### Description

These functions allow you to capture the side-effects of a function call including printed output, messages and warnings. They are used to evaluate code for `expect_output()`, `expect_message()`, `expect_warning()`, and `expect_silent()`.

### Usage

    capture_condition(code)

    capture_error(code)

    capture_expectation(code)

    capture_message(code)

    capture_warning(code)

    capture_messages(code)

    capture_warnings(code)

### Arguments

`code` | Code to evaluate

### Value

Singular functions (`capture_condition`, `capture_expectation` etc) return a condition object. `capture_messages()` and `capture_warnings` return a character vector of message text.

### Examples

    f <- function() {
      message("First")
      warning("Second")
      message("Third")
    }

    capture_message(f())
    capture_messages(f())

    capture_warning(f())
    capture_warnings(f())

    # Condition will capture anything
    capture_condition(f())

[Package testthat version 2.0.1 Index]