Use Labels, rather than PathFragments, to represent Skylark loads internally. The load location for a Skylark Aspect is specified via a PathFragment, for consistency with current non-Aspect Skylark loads.

This should be a semantics-preserving change for users. In a subsequent CL, I'll change the Skylark syntax to allow load statements to use labels as well as paths, with the goal of eventually deprecating the latter.

Also:

- Removed the hack for handling relative loads in the prelude file.

- Refactored some redundant functionality in PackageFunction and SkylarkImportLookupFunction for handling loads.

- Removed the ability to put the BUILD file for the package containing a Skylark file under a different package root than the Skylark file itself. This functionality isn't currently used and is inconsistent with Blaze's handling of the package path elsewhere.

- Added BUILD files to a number of tests that load Skylark files; this is consistent with the requirement that all Skylark files need to be part of some package.

- Changed the constants used to set the location of the prelude file from paths to labels.

--
MOS_MIGRATED_REVID=107741568

1 files changed, 2 insertions, 2 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ErrorReadingSkylarkExtensionException.java b/src/main/java/com/google/devtools/build/lib/skyframe/ErrorReadingSkylarkExtensionException.java
index 6df01130fe..af4f039769 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ErrorReadingSkylarkExtensionException.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ErrorReadingSkylarkExtensionException.java
@@ -15,7 +15,7 @@ package com.google.devtools.build.lib.skyframe;
 
 /** Indicates some sort of IO error while dealing with a Skylark extension. */
 public class ErrorReadingSkylarkExtensionException extends Exception {
-  public ErrorReadingSkylarkExtensionException(String message) {
-    super(message);
+  public ErrorReadingSkylarkExtensionException(Exception e) {
+    super(e.getMessage(), e);
   }
 }