Separate core and std modules

The core module only contains the tiny kernel pull parser and common
types. This kernel is intendend to be used to implement higher-level XML
libraries including:

 - a DOM;
 - XML document manipulation utilities;
 - XML validation;
 - XPath;
 - and so on.

Default implementation for all these features is provided by the std
module where the DOM is represented as a tree and procesors are used to
perform various validations.

The pull parser is also more strict on syntax rules.
It won’t accept new tags after the root has been closed,
according to the `document` syntax rule of the specification.

Author: satabin

.scalariform.conf

@@ -2,5 +2,6 @@ autoformat=true
 alignSingleLineCaseStatements=true
 doubleIndentConstructorArguments=true
 doubleIndentMethodDeclaration=true
+doubleIndentClassDeclaration=true
 multilineScaladocCommentsStartOnFirstLine=true
 danglingCloseParenthesis=Prevent

build.sbt

@@ -4,6 +4,9 @@ val scala212 = "2.12.3"
 lazy val commonSettings = Seq(
   organization := "org.gnieh",
   scalaVersion := scala212,
+  libraryDependencies ++= Seq(
+    "org.scalatest" %% "scalatest" % "3.0.3" % Test,
+    "com.github.pathikrit" %% "better-files" % "2.17.1" % Test),
   version := "0.1.0-SNAPSHOT",
   description := "Scala XML library revisited",
   licenses += ("The Apache Software License, Version 2.0" -> url("http://www.apache.org/licenses/LICENSE-2.0.txt")),
@@ -13,7 +16,7 @@ lazy val commonSettings = Seq(
   fork in test := true,
   scalacOptions in (Compile,doc) ++= Seq("-groups", "-implicits"),
   autoAPIMappings := true,
-  scalacOptions ++= Seq("-deprecation", "-feature", "-unchecked")) ++ publishSettings
+  scalacOptions ++= Seq("-deprecation", "-feature", "-unchecked", "-Ypartial-unification")) ++ publishSettings
 
 lazy val publishSettings = Seq(
   publishMavenStyle := true,
@@ -56,13 +59,17 @@ lazy val xml = project.in(file("."))
   .settings(
     name := "xml",
     packagedArtifacts := Map())
-  .aggregate(core)
+  .aggregate(core, std)
 
 lazy val core = project.in(file("core"))
   .enablePlugins(ScoverageSbtPlugin)
   .settings(commonSettings)
   .settings(
-    name := "xml-core",
-    libraryDependencies ++= Seq(
-      "org.scalatest" %% "scalatest" % "3.0.3" % Test,
-      "com.github.pathikrit" %% "better-files" % "2.17.1" % Test))
+    name := "xml-core")
+
+lazy val std = project.in(file("std"))
+  .enablePlugins(ScoverageSbtPlugin)
+  .settings(commonSettings)
+  .settings(
+    name := "xml-std")
+  .dependsOn(core)

core/src/main/scala/scalax/xml/Position.scala

@@ -0,0 +1,26 @@
+/*
+* Copyright (c) 2017 Lucas Satabin
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+package scalax.xml
+
+trait Position
+
+object NoPosition extends Position {
+  override def toString = "<no position>"
+}
+
+class LineColumnPosition(line: Int, column: Int) extends Position {
+  override def toString = f"[$line.$column]"
+}

core/src/main/scala/scalax/xml/Utils.scala

@@ -0,0 +1,23 @@
+/*
+* Copyright (c) 2017 Lucas Satabin
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+package scalax.xml
+
+object XmlUtils {
+
+  def isXmlWhitespace(c: Char): Boolean =
+    c == ' ' || c == '\t' || c == '\r' || c == '\n'
+
+}

core/src/main/scala/scalax/xml/XmlException.scala

@@ -15,9 +15,9 @@
 */
 package scalax.xml
 
-case class XmlException(line: Int, column: Int, error: XmlError, message: String) extends Exception {
+case class XmlException(position: Position, error: XmlError, message: String) extends Exception {
 
   override def getMessage: String =
-    f"{$line.$column]: ${error.name} $message"
+    f"$position: ${error.name} $message"
 
 }

core/src/main/scala/scalax/xml/errors.scala

@@ -0,0 +1,26 @@
+/*
+* Copyright (c) 2017 Lucas Satabin
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+package scalax.xml
+
+/** All errors encountered in processing an Xml documents
+ *  have a kind.
+ *  These errors are unique code defined in the various normative documents
+ *  and recommendations.
+ */
+abstract class XmlError(val name: String)
+
+/** Represents a syntax error according to an XML production rule. */
+case class XmlSyntax(id: String) extends XmlError(f"XML [$id]")