From 0be7a89cbf65738e3351a9dc102ca1bec83cb9a4 Mon Sep 17 00:00:00 2001
From: Liam Miller-Cushon <cushon@google.com>
Date: Thu, 25 Jan 2024 13:48:56 -0800
Subject: [PATCH] Work around a javac end position bug for empty statements

See https://bugs.openjdk.org/browse/JDK-8324736

Fixes https://github.com/google/error-prone/issues/4245

PiperOrigin-RevId: 601554857
---
 .../bugpatterns/EmptyTopLevelDeclaration.java       | 12 +++++++++++-
 .../bugpatterns/EmptyTopLevelDeclarationTest.java   | 13 +++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/com/google/errorprone/bugpatterns/EmptyTopLevelDeclaration.java b/core/src/main/java/com/google/errorprone/bugpatterns/EmptyTopLevelDeclaration.java
index a896c2bc295..622b5a662f6 100644
--- a/core/src/main/java/com/google/errorprone/bugpatterns/EmptyTopLevelDeclaration.java
+++ b/core/src/main/java/com/google/errorprone/bugpatterns/EmptyTopLevelDeclaration.java
@@ -19,6 +19,7 @@
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.matchers.Description.NO_MATCH;
+import static com.google.errorprone.util.ASTHelpers.getStartPosition;
 
 import com.google.common.collect.ImmutableList;
 import com.google.errorprone.BugPattern;
@@ -44,7 +45,16 @@ public Description matchCompilationUnit(CompilationUnitTree tree, VisitorState s
       return NO_MATCH;
     }
     SuggestedFix.Builder fixBuilder = SuggestedFix.builder();
-    toDelete.forEach(fixBuilder::delete);
+    toDelete.forEach(
+        x -> {
+          int start = getStartPosition(x);
+          int end = state.getEndPosition(x);
+          if (end <= start) {
+            // work around https://bugs.openjdk.org/browse/JDK-8324736
+            end = start + 1;
+          }
+          fixBuilder.replace(start, end, "");
+        });
     return describeMatch(toDelete.get(0), fixBuilder.build());
   }
 }
diff --git a/core/src/test/java/com/google/errorprone/bugpatterns/EmptyTopLevelDeclarationTest.java b/core/src/test/java/com/google/errorprone/bugpatterns/EmptyTopLevelDeclarationTest.java
index cfc534685c9..d69211cca73 100644
--- a/core/src/test/java/com/google/errorprone/bugpatterns/EmptyTopLevelDeclarationTest.java
+++ b/core/src/test/java/com/google/errorprone/bugpatterns/EmptyTopLevelDeclarationTest.java
@@ -43,4 +43,17 @@ public void positive() {
             "class One {};")
         .doTest();
   }
+
+  // https://github.com/google/error-prone/issues/4245
+  @Test
+  public void noImports() {
+    compilationHelper
+        .addSourceLines(
+            "ReproFile.java", //
+            "package errorpronecrash;",
+            "// BUG: Diagnostic contains: Did you mean to remove this line?",
+            ";",
+            "public class ReproFile {}")
+        .doTest();
+  }
 }