assertThat: how to invert containsString

Question

I have an assertion that checks if a string is present in the currently selected text:

import static org.junit.Assert.assertThat;
import static org.hamcrest.Matchers.containsString;
assertThat(latest.getText(), containsString(targetString));

But I can't find the right way to write an assertion that checks if a string is NOT contained in the text.

I tried

assertThat(latest.getText(), not(containsString(targetString)));

but get an error

the method not(Matcher <String>) is undefined

What is the way to do this?

no: I tried that too, but it says 'the operator ! is undefined for the matcher type Matcher ' — ruud, May 14 '20 at 07:53
Thank you Joe, that works indeed. I have done an upvote, since a cannot accept it as an answer. — ruud, May 14 '20 at 07:55

score 5 · Accepted Answer · answered May 13 '20 at 14:22

to me this is working and raises an error:

import static org.junit.Assert.assertThat;
import static org.hamcrest.Matchers.containsString;
import static org.hamcrest.Matchers.not;

class Main {
  public static void main(String[] args) {
    String test = "qwerty";
    String contained = "ert";
    assertThat(test, not(containsString(contained)));
  }
}

score 1 · Answer 2 · answered May 13 '20 at 14:02

1

You could switch to AssertJ and then use

assertThat(latest.getText()).doesNotContain(targetString);

answered May 13 '20 at 14:02

tomasulo

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assertThat: how to invert containsString

2 Answers2