Fix allowed characters in package and restore a comment

Follow-up to commit cae43035f9e6957ad05fec047d015a98aa53f97b

--
PiperOrigin-RevId: 148450575
MOS_MIGRATED_REVID=148450575

1 files changed, 9 insertions, 1 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/cmdline/LabelValidator.java b/src/main/java/com/google/devtools/build/lib/cmdline/LabelValidator.java
index 4d86f972da..035bfbbe4d 100644
--- a/src/main/java/com/google/devtools/build/lib/cmdline/LabelValidator.java
+++ b/src/main/java/com/google/devtools/build/lib/cmdline/LabelValidator.java
@@ -39,7 +39,11 @@ public final class LabelValidator {
    * Matches characters allowed in package name (allowed are A-Z, a-z, 0-9, '/', '-', '.' and '_')
    */
   private static final CharMatcher ALLOWED_CHARACTERS_IN_PACKAGE_NAME =
-      CharMatcher.javaLetterOrDigit().or(CharMatcher.anyOf("/-._")).precomputed();
+      CharMatcher.inRange('0', '9')
+          .or(CharMatcher.inRange('a', 'z'))
+          .or(CharMatcher.inRange('A', 'Z'))
+          .or(CharMatcher.anyOf("/-._"))
+          .precomputed();
 
   /**
    * Matches characters allowed in target names regardless of context.
@@ -121,6 +125,10 @@ public final class LabelValidator {
    */
   @Nullable
   public static String validateTargetName(String targetName) {
+    // We allow labels equaling '.' or ending in '/.' for now. If we ever
+    // actually configure the target we will report an error, but they are permitted for
+    // data directories.
+
     // Code optimized for the common case: success.
     int len = targetName.length();
     if (len == 0) {