improve readme, add block syntax for abstract assertions

Author: memoizr

README.md

@@ -1,2 +1,47 @@
-# assertk
-A kotlin-friendly wrapper for assertJd
+# AssertK - Fluent assertions for Kotlin
+AssertK provides a Kotlin-friendly syntax for using the amazing AssertJ assertion framework.
+
+###Simple assertions
+```
+assert that Unit isEqualTo Unit
+assert that Any() isNotEqualTo Any()
+assert that Any() _is notNull
+assert that nullObject _is null
+assert that anObject isInstance of<Any>()
+assert that Any() describedAs "A labeled object" isInstance of<Unit>()
+```
+
+###Chained syntax
+```
+assert that Unit isNotEqualTo Any() isEqualTo Unit _is notNull isInstance of<Any>()
+```
+
+###Block syntax
+```
+assert that Any() isSuchThat {
+    it _is notNull
+    it isInstance of<Any>()
+    it isNotEqualTo Unit
+    it isNotEqualTo Any()
+}
+```
+
+##Assertions on exceptions
+###Chained syntax
+```
+assert thatExceptionIsThrownBy { failFunction() } hasMessageContaining "foo" hasCause Throwable()
+```
+
+###Block syntax
+```
+assert thatExceptionIsThrownBy {
+    throw Throwable("exception foo", Throwable())
+} and {
+    it hasMessage "exception foo"
+    it hasCause Throwable()
+    it hasCauseExactlyInstanceOf Throwable::class.java
+    it hasMessageContaining "foo"
+    it hasMessageStartingWith "ex"
+    it hasMessageEndingWith "foo"
+}
+```

src/main/kotlin/com/memozr/assertk/AbstractAssertBuilder.kt

@@ -47,4 +47,9 @@ class AbstractAssertBuilder<T : Any>(other: T?) {
         assertion.`as`(description)
         return this
     }
+
+    infix fun isSuchThat(assertionBlock: AbstractAssertBuilder<T>.(AbstractAssertBuilder<T>) -> Unit): AbstractAssertBuilder<T> {
+        assertionBlock(this)
+        return this
+    }
 }

src/test/kotlin/com/memozr/assertk/AbstractAssertBuilderTest.kt

@@ -59,4 +59,21 @@ class AbstractAssertBuilderTest {
             assert that Any() describedAs "A labeled object" isInstance of<Unit>()
         } hasMessageContaining "A labeled object"
     }
+
+    @Test
+    fun `block assertions`() {
+        assert that Any() isSuchThat {
+            it _is notNull
+            it isInstance of<Any>()
+            it isNotEqualTo Unit
+            it isNotEqualTo Any()
+        }
+
+        assert thatExceptionIsThrownBy {
+            assert that Any() isSuchThat {
+                it _is null
+                it isInstance of<Unit>()
+            }
+        }
+    }
 }