In the MutableList API, make an internal unsafe method public

This method acts as an "escape hatch" for mutating a list regardless of Mutability. It should be avoided if at all possible.

RELNOTES: None
PiperOrigin-RevId: 164716286

1 files changed, 11 insertions, 2 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkList.java b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkList.java
index bab6df740a..1f90a65c51 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkList.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkList.java
@@ -335,8 +335,17 @@ public abstract class SkylarkList<E> extends BaseMutableList<E>
           ImmutableList.copyOf(contents), env == null ? null : env.mutability());
     }
 
-    /** Appends the given elements to the end of the list, without calling {@link #checkMutable}. */
-    private void addAllUnsafe(Iterable<? extends E> elements) {
+    /**
+     * Appends the given elements to the end of the list, without calling {@link #checkMutable}.
+     *
+     * <p><em>Warning:</em> This method should never be used by a caller that cares about respecting
+     * mutability restrictions. Such callers should instead use the safe {@link #addAll(Iterable,
+     * Location, Mutability)} method below. This unsafe variant is only public in order to provide
+     * an "escape hatch" for when ordinary mutability restrictions are inapplicable, e.g. for
+     * constructing lists from outside a Skylark environment and where it's impossible for multiple
+     * threads to observe the value at once.
+     */
+    public void addAllUnsafe(Iterable<? extends E> elements) {
       Iterables.addAll(contents, elements);
     }