add readers for java.time.LocalDate and Period (#44)

* add readers for java.time.LocalDate and Period

* fix tests

turns out I missed putting the interpolated call into the 'is' comprehension.

src/main/scala/net/ceedubs/ficus/Ficus.scala

@@ -7,7 +7,7 @@ import scala.language.implicitConversions
 trait FicusInstances extends AnyValReaders with StringReader with SymbolReader with OptionReader
     with CollectionReaders with ConfigReader with DurationReaders
     with TryReader with ConfigValueReader with BigNumberReaders
-    with ISOZonedDateTimeReader
+    with ISOZonedDateTimeReader with PeriodReader with LocalDateReader
 
 object Ficus extends FicusInstances {
   implicit def toFicusConfig(config: Config): FicusConfig = SimpleFicusConfig(config)

src/main/scala/net/ceedubs/ficus/readers/AllValueReaderInstances.scala

@@ -2,6 +2,6 @@ package net.ceedubs.ficus.readers
 
 trait AllValueReaderInstances extends AnyValReaders with StringReader with SymbolReader with OptionReader
   with CollectionReaders with ConfigReader with DurationReaders with ArbitraryTypeReader
-  with TryReader with ConfigValueReader
+  with TryReader with ConfigValueReader with PeriodReader with LocalDateReader
 
 object AllValueReaderInstances extends AllValueReaderInstances

src/main/scala/net/ceedubs/ficus/readers/LocalDateReader.scala

@@ -0,0 +1,15 @@
+package net.ceedubs.ficus.readers
+
+import java.time.LocalDate
+
+import com.typesafe.config.Config
+
+trait LocalDateReader {
+  implicit val localDateReader: ValueReader[LocalDate] = new ValueReader[LocalDate] {
+    override def read(config: Config, path: String): LocalDate = {
+      LocalDate.parse(config.getString(path))
+    }
+  }
+}
+
+object LocalDateReader extends LocalDateReader

src/main/scala/net/ceedubs/ficus/readers/PeriodReader.scala

@@ -0,0 +1,15 @@
+package net.ceedubs.ficus.readers
+
+import java.time.Period
+
+import com.typesafe.config.Config
+
+trait PeriodReader {
+  implicit val periodReader: ValueReader[Period] = new ValueReader[Period] {
+    override def read(config: Config, path: String): Period = {
+      Period.parse(config.getString(path))
+    }
+  }
+}
+
+object PeriodReader extends PeriodReader

src/test/scala/net/ceedubs/ficus/readers/LocalDateReaderSpec.scala

@@ -0,0 +1,25 @@
+package net.ceedubs.ficus
+package readers
+
+import java.time.LocalDate
+import com.typesafe.config.ConfigFactory
+import Ficus.{ toFicusConfig, localDateReader }
+
+
+class LocalDateReaderSpec extends Spec { def is = s2"""
+  The LocalDateReader should 
+    read a LocalDate in ISO format without a time-zone: $readLocalDate
+  """
+
+  def readLocalDate = {
+    val cfg = ConfigFactory.parseString(
+      s"""
+         | foo {
+         |    date = "2003-01-03"
+         | }
+       """.stripMargin)
+    val localDate = cfg.as[LocalDate]("foo.date")
+    val expected = LocalDate.of(2003,1,3)
+    localDate should_==(expected)
+  }
+}

src/test/scala/net/ceedubs/ficus/readers/PeriodReaderSpec.scala

@@ -0,0 +1,37 @@
+package net.ceedubs.ficus
+package readers
+
+import java.time.Period
+import com.typesafe.config.ConfigFactory
+import Ficus.{ toFicusConfig, periodReader }
+
+class PeriodReaderSpec extends Spec { def is = s2"""
+  The PeriodReader should 
+    read a Period in ISO-8601 format $readPeriod
+    read a negative Period $readNegativePeriod
+  """
+
+  def readPeriod = {
+    val cfg = ConfigFactory.parseString(
+      s"""
+         | foo {
+         |    interval = "P1Y3M10D"
+         | }
+       """.stripMargin)
+    val period = cfg.as[Period]("foo.interval")
+    val expected = Period.of(1,3,10)
+    period should_==(expected)
+  }
+
+  def readNegativePeriod = {
+    val cfg = ConfigFactory.parseString(
+      s"""
+         | foo {
+         |    interval = "P-1Y10M3D"
+         | }
+       """.stripMargin)
+    val period = cfg.as[Period]("foo.interval")
+    val expected = Period.of(-1,10,3)
+    period should_==(expected)
+  }
+}