VerifyThat

Make testing validation more fluent and understandable.

Example:

String test = "asd";
Verify.that(test)
      .named("Check string {}", test)           // Name the test
      .sizeIsGreaterThan(2)                     // size > 2
      .contains("sd")                           // contains string "sd"
      .contains('q');                           // ERROR!!!
      
// ComparisionException: (Check string asd) Expected [contains q] but got [[a, s, d]]

String:

Verify.that("asdasd")
      .matches("\\w+")      // regex pattern
      .sizeIsGreaterThan(3) // length > 3
      .startsWith("as")     // starts with "as"
      .contains('d')        // contains letter d
      .notContains('q');    // contains letter q

Arrays:

Verify.that(new Object[] {1, 2, 3})
      .isNotEmpty()                 // size > 0
      .sizeIsGreaterThan(1)         // size > 1
      .sizeIsLessThan(4)            // size < 4
      .contains(1, 3)               // contains 1, contains 3
      .arrayEquals(1, 2, 3)         // is same as [1, 2, 3]

Map:

Verify.that(map)
      .sizeIsGreaterThan(1)     // size > 1
      .sizeIsLessThan(4)        // size < 4       
      .containsKey("a")         // contains key=a
      .containsValue(1)         // contains value=1
      .containsKeyValue("a", 1);// contains (a:1)

Runnable:

Verify.that(() -> { throw new IOException("BAD THINGS", new Exception()); })
      .timeout(10, TimeUnit.SECONDS)         // 10s timeout
      .throwsException(IOException.class)    // Caught IOException
      .messageIs("BAD THINGS")               // Exception message = "BAD THINGS"
      .causeIs(Exception.class);             // Cause of exception is Exception

Classes:

// Validation of modifiers
Verify.that(getClass()).is(ReflectModifier.PUBLIC);
 
// Verify existance of methods and fields matching conditions
Verify.that(Runnable.class)
      .matcher()
      .hasMethod()
      .typeIs(Void.TYPE)
      .getMatched()
      .sizeIs(1);

VCS:

https://jitpack.io/#kylepls/VerifyThat/