[backport] SI-9060 Backpatch fifth-edition names

Because the compiler and library share some code in this
version, compiler must exclude xml tags that look like
Scala operators, such as `<:`.

This is an upstream port of:
scala-xml/commit/968f7bd94e934c781c19e25847ab09ac98cfbaf6

3 files changed, 25 insertions, 39 deletions

diff --git a/src/compiler/scala/tools/nsc/ast/parser/Scanners.scala b/src/compiler/scala/tools/nsc/ast/parser/Scanners.scala
index 8d295a28d0..3ee7941995 100644
--- a/src/compiler/scala/tools/nsc/ast/parser/Scanners.scala
+++ b/src/compiler/scala/tools/nsc/ast/parser/Scanners.scala
@@ -367,7 +367,9 @@ trait Scanners extends ScannersCommon {
             val last = if (charOffset >= 2) buf(charOffset - 2) else ' '
             nextChar()
             last match {
-              case ' ' | '\t' | '\n' | '{' | '(' | '>' if isNameStart(ch) || ch == '!' || ch == '?' =>
+              // exclude valid xml names that happen to be Scala operator chars
+              case ' ' | '\t' | '\n' | '{' | '(' | '>' if (isNameStart(ch) && ch != ':' && !isSpecial(ch))
+                  || ch == '!' || ch == '?' =>
                 token = XMLSTART
               case _ =>
                 // Console.println("found '<', but last is '"+in.last+"'"); // DEBUG
diff --git a/src/library/scala/xml/parsing/TokenTests.scala b/src/library/scala/xml/parsing/TokenTests.scala
index c9cafaeea1..ce7accbd98 100644
--- a/src/library/scala/xml/parsing/TokenTests.scala
+++ b/src/library/scala/xml/parsing/TokenTests.scala
@@ -30,43 +30,25 @@ trait TokenTests {
   def isAlpha(c: Char) = (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z')
   def isAlphaDigit(c: Char) = isAlpha(c) || (c >= '0' && c <= '9')
 
-  /** {{{
-   *  NameChar ::= Letter | Digit | '.' | '-' | '_' | ':'
-   *             | CombiningChar | Extender
-   *  }}}
-   *  See [4] and Appendix B of XML 1.0 specification.
-  */
-  def isNameChar(ch: Char) = {
-    import java.lang.Character._
-    // The constants represent groups Mc, Me, Mn, Lm, and Nd.
-
-    isNameStart(ch) || (getType(ch).toByte match {
-      case COMBINING_SPACING_MARK |
-              ENCLOSING_MARK | NON_SPACING_MARK |
-              MODIFIER_LETTER | DECIMAL_DIGIT_NUMBER => true
-      case _                                         => ".-:" contains ch
-    })
-  }
-
-  /** {{{
-   *  NameStart ::= ( Letter | '_' )
-   *  }}}
-   *  where Letter means in one of the Unicode general
-   *  categories `{ Ll, Lu, Lo, Lt, Nl }`.
-   *
-   *  We do not allow a name to start with `:`.
-   *  See [3] and Appendix B of XML 1.0 specification
-   */
-  def isNameStart(ch: Char) = {
-    import java.lang.Character._
-
-    getType(ch).toByte match {
-      case LOWERCASE_LETTER |
-              UPPERCASE_LETTER | OTHER_LETTER |
-              TITLECASE_LETTER | LETTER_NUMBER => true
-      case _                                   => ch == '_'
-    }
-  }
+  def isNameChar(c: Char): Boolean = (
+    isNameStart(c) ||
+    (c >= '0' && c <= '9') ||
+    c == '-' ||
+    c == '.' ||
+    c == 0xB7 ||
+    (c >= 0x300 && c <= 0x36F) ||
+    (c >= 0x203F && c <= 0x2040)
+  )
+  def isNameStart(c: Char): Boolean = (
+         if (c < 0x00C0)  isAlpha(c) || c == ':' || c == '_'
+    else if (c < 0x0300)  c != 0xD7 && c != 0xF7
+    else if (c < 0x2000)  c >= 0x370 && c != 0x37E
+    else if (c < 0x3001)  c == 0x200C || c == 0x200D || (0x2070 to 0x218F contains c) ||
+                          (0x2C00 to 0x2FEF contains c)
+    else if (c < 0xD800)  true
+    else if (c < 0x10000) (0xF900 to 0xFDCF contains c) || (0xFDF0 to 0xFFFD contains c)
+    else                  false // codepoint < 0xF0000
+  )
 
   /** {{{
    *  Name ::= ( Letter | '_' ) (NameChar)*
diff --git a/test/files/jvm/unittest_xml.scala b/test/files/jvm/unittest_xml.scala
index 106334e625..9ffd459fde 100644
--- a/test/files/jvm/unittest_xml.scala
+++ b/test/files/jvm/unittest_xml.scala
@@ -62,7 +62,9 @@ object Test {
   object UtilityTest {
     def run() {
       assert(Utility.isNameStart('b'))
-      assert(!Utility.isNameStart(':'))
+
+      // no longer: this was a convenience for the implementation, not to spec.
+      //assert(!Utility.isNameStart(':'))
 
       val x = <foo>
                  <toomuchws/>