Split ScipShardWriter into a pure ScipShards utility

ScipShardWriter was a static-only utility named like a stateful writer.
Move the pure merge logic into ScipShards and inline the six-line file
I/O at the only call site (SemanticdbTaskListener.onFinishedAnalyze).

Author: jupblb

…ph/semanticdb_javac/ScipShardWriter.java …cegraph/semanticdb_javac/ScipShards.javasemanticdb-javac/src/main/java/com/sourcegraph/semanticdb_javac/ScipShardWriter.java renamed to semanticdb-javac/src/main/java/com/sourcegraph/semanticdb_javac/ScipShards.java semanticdb-javac/src/main/java/com/sourcegraph/semanticdb_javac/ScipShardWriter.java renamed to semanticdb-javac/src/main/java/com/sourcegraph/semanticdb_javac/ScipShards.java

@@ -2,45 +2,24 @@
 
 import org.scip_code.scip.Document;
 import org.scip_code.scip.Index;
-import org.scip_code.scip.Occurrence;
 import org.scip_code.scip.Relationship;
 import org.scip_code.scip.SymbolInformation;
 
-import java.io.IOException;
-import java.io.InputStream;
-import java.nio.file.Files;
-import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
 import java.util.List;
 
 /**
- * Writes and merges per-source SCIP shards produced by the compiler plugin.
+ * Pure merge helpers for SCIP shards produced by the compiler plugin.
  *
  * <p>Each source file produces a self-contained {@link Index} shard containing a single {@link
- * Document}. When a shard already exists on disk (e.g. during annotation processing rounds), the
- * new document is merged into the existing one, deduplicating occurrences, symbols and
- * relationships.
+ * Document}. When the compiler runs multiple analyze rounds for the same source (e.g. during
+ * annotation processing), the freshly built shard is merged with the one already on disk by
+ * combining their document lists and deduplicating occurrences, symbols and relationships.
  */
-public final class ScipShardWriter {
+public final class ScipShards {
 
-  private ScipShardWriter() {}
-
-  /**
-   * Writes the given {@code shard} to {@code output}, creating parent directories as needed. If
-   * {@code output} already exists, the existing shard is parsed and merged with the new one.
-   */
-  public static void writeOrMerge(Path output, Index shard) throws IOException {
-    Files.createDirectories(output.getParent());
-    if (Files.exists(output)) {
-      Index existing;
-      try (InputStream is = Files.newInputStream(output)) {
-        existing = Index.parseFrom(is);
-      }
-      shard = merge(existing, shard);
-    }
-    Files.write(output, shard.toByteArray());
-  }
+  private ScipShards() {}
 
   /**
    * Merges two SCIP shards by combining their document lists. Documents that share a {@code

semanticdb-javac/src/main/java/com/sourcegraph/semanticdb_javac/SemanticdbTaskListener.java

@@ -11,6 +11,7 @@
 import javax.tools.JavaFileObject;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.io.PrintWriter;
 import java.net.URI;
 import java.nio.file.Files;
@@ -114,7 +115,13 @@ private void onFinishedAnalyze(TaskEvent e) {
       Index shard =
           new ScipVisitor(globals, e.getCompilationUnit(), options, types, trees, elements)
               .buildShard(e.getCompilationUnit());
-      ScipShardWriter.writeOrMerge(shardPath, shard);
+      Files.createDirectories(shardPath.getParent());
+      if (Files.exists(shardPath)) {
+        try (InputStream is = Files.newInputStream(shardPath)) {
+          shard = ScipShards.merge(Index.parseFrom(is), shard);
+        }
+      }
+      Files.write(shardPath, shard.toByteArray());
     } catch (IOException ex) {
       this.reportException(ex, e);
     }