PackageNamesChecker should allow only lowercase alphabets (#18)

Author: anilkumarmyla

src/main/resources/default_config.xml

@@ -68,7 +68,7 @@
   <check class="org.scalastyle.scalariform.PackageNamesChecker" level="warning" enabled="true">
     <parameters>
       <parameter name="regex">
-        <![CDATA[^[a-z][A-Za-z]*$]]>
+        <![CDATA[^[a-z]+$]]>
       </parameter>
     </parameters>
   </check>

src/main/resources/scalastyle_definition.xml

@@ -39,7 +39,7 @@
     </checker>
     <checker class="org.scalastyle.scalariform.PackageNamesChecker" id="package.name" defaultLevel="warning">
         <parameters>
-            <parameter name="regex" type="string" default="^[a-z][A-Za-z]*$" />
+            <parameter name="regex" type="string" default="^[a-z]+$" />
         </parameters>
     </checker>
     <checker class="org.scalastyle.scalariform.PackageObjectNamesChecker" id="package.object.name" defaultLevel="warning">

src/main/resources/scalastyle_documentation.xml

@@ -693,7 +693,7 @@ To bring consistency with how comments should be formatted, leave a space right
  <![CDATA[
     <check level="warning" class="org.scalastyle.scalariform.PackageNamesChecker" enabled="true">
       <parameters>
-        <parameter name="regex">^[a-z][A-Za-z]*$</parameter>
+        <parameter name="regex">^[a-z]+$</parameter>
       </parameters>
     </check>
  ]]>

src/main/scala/org/scalastyle/scalariform/ClassNamesChecker.scala

@@ -81,7 +81,7 @@ class ObjectNamesChecker extends ScalariformChecker {
 }
 
 class PackageNamesChecker extends ScalariformChecker {
-  val DefaultRegex = "^[a-z][A-Za-z]*$"
+  val DefaultRegex = "^[a-z]+$"
   val errorKey = "package.name"
 
   def verify(ast: CompilationUnit): List[PositionError] = {

src/test/scala/org/scalastyle/scalariform/ClassNamesCheckerTest.scala

@@ -118,7 +118,15 @@ package foobar
 package FooBar
 """
 
-    assertErrors(List(columnError(2, 8, List("^[a-z][A-Za-z]*$"))), source)
+    assertErrors(List(columnError(2, 8, List("^[a-z]+$"))), source)
+  }
+
+  @Test def testSinglePartCamelCaseError(): Unit = {
+    val source = """
+package fooBar
+"""
+
+    assertErrors(List(columnError(2, 8, List("^[a-z]+$"))), source)
   }
 
   @Test def testMultiPartNoError(): Unit = {
@@ -134,7 +142,15 @@ package abc.foobar
 package abc.foo_bar
 """
 
-    assertErrors(List(columnError(2, 12, List("^[a-z][A-Za-z]*$"))), source)
+    assertErrors(List(columnError(2, 12, List("^[a-z]+$"))), source)
+  }
+
+  @Test def testMultiPartCamelCaseError(): Unit = {
+    val source = """
+package abc.fooBar
+"""
+
+    assertErrors(List(columnError(2, 12, List("^[a-z]+$"))), source)
   }
 
   @Test def testPackageObjectNoError(): Unit = {
@@ -162,7 +178,7 @@ package foo
 package Bar
 """
 
-    assertErrors(List(columnError(3, 8, List("^[a-z][A-Za-z]*$"))), source)
+    assertErrors(List(columnError(3, 8, List("^[a-z]+$"))), source)
   }
 
   @Test def testMultiLinePackageMultipleError(): Unit = {
@@ -172,7 +188,7 @@ package Bar
 """
 
     assertErrors(
-      List(columnError(2, 8, List("^[a-z][A-Za-z]*$")), columnError(3, 8, List("^[a-z][A-Za-z]*$"))),
+      List(columnError(2, 8, List("^[a-z]+$")), columnError(3, 8, List("^[a-z]+$"))),
       source
     )
   }