lucassales2 / pretty-print

pretty print module for the jvm

pretty-print - pp

Adds a pp(Any?) and T.pp() method to pretty print any Java or Kotlin object.

pp(Any?) takes any object and prints it in a pretty format. T.pp() pretty prints inside a method chain when called on an object inline.

Approach	Instruction
Gradle	testImplementation "com.tylerthrailkill.helpers:pretty-print:{version}"
Maven	<dependency> <groupId>com.tylerthrailkill.helpers</groupId> <artifactId>pretty-print</artifactId> <version>{version}</version> </dependency>

API

pp(obj: Any?, tabSize: Int = 2, printStream: PrintStream = System.out, wrappedLineWidth: Int = 80)

tabSize changes the number of spaces used to indent each level of the output. Default is 2.

printStream changes the PrintStream you are printing to. Default is System.out.

wrappedLineWidth changes the number of characters allowed before wrapping in a multiline string. Default is 80.

Examples

Main API

Top level method

data class TinyObject(var int: Int)
pp(TinyObject(1))

TinyObject(
  int = 1
)

Inline method

data class TinyObject(var int: Int)
fun callSomething(obj: Any?) {
    println("inline wrapper function entered")
}
callSomething(TinyObject(1).pp())

TinyObject(
  int = 1
)
inline wrapper function entered

Other uses

List

pp(listOf("1", 2, 3.0, true))

[
  "1",
  2,
  3.0,
  true
]

Object with list

data class OL(val list: List<String>)
pp(OL(listOf("1")))

OL(
  list = [
           "1"
         ]
)

Map

pp(mapOf("key1" to "value1", "key2" to "value2"))

{
  "key1" -> "value1",
  "key2" -> "value2"
}

Object with map

data class OM(val map: Map<Any, Any>)
pp(OM(mapOf(1 to "value", "key" to 1)))

OM(
  map = {
          1 -> "value",
          "key" -> 1
        }
)

Multiline strings

pp("Goodbye, cruel world. Goodbye, cruel lamp.", wrappedLineWidth = 22)

"""
Goodbye, cruel world.
Goodbye, cruel lamp.
"""

Multiline strings with unicode line breaking

pp("Goodbye, cruel world. Good­bye, cruel lamp.", wrappedLineWidth = 27)

"""
Goodbye, cruel world. Good­
bye, cruel lamp.
"""

pp("😍️🥞😍️", wrappedLineWidth = 3)

"""
😍️
🥞
😍️
"""

Multiple fields

pp(SmallObject("Goodbye, cruel world. Goodbye, cruel lamp.", 1))

SmallObject(
  field1 = "Goodbye, cruel world. Goodbye, cruel lamp."
  field2 = 1
)

Different indent size

data class TinyObject(var int: Int)
pp(TinyObject(1), tabSize = 0)

TinyObject(
int = 1
)

data class TinyObject(var int: Int)
pp(TinyObject(1), tabSize = 10)

TinyObject(
          int = 1
)

Different output stream

val stream = ByteArrayOutputStream()
pp(TinyObject(1), printStream = PrintStream(stream))
println(":::")
print(stream.toString())
println(":::")

:::
TinyObject(
  int = 1
)
:::

Cyclic references

data class O1(var c: O2? = null)
data class O2(var c: O1? = null)
val sco1 = O1()
val sco2 = O2(sco1)
sco1.c = sco2
pp(sco1)

O1(
  c = O2(
    c = cyclic reference detected for 50699452
  )
)[$id=50699452]

ToDo

• Test nullability cases
• implement pretty print for java* classes
• fix unicode line breaking with icu4j library characters