refactor(language): use a Cleaner for cleanup

Author: ObserverOfTime

scripts/jextract.ps1

@@ -181,7 +181,3 @@ $env:package = 'io.github.treesitter.jtreesitter.internal'
     -I "$($args[0])/core/lib/include" `
     -DTREE_SITTER_HIDE_SYMBOLS `
     "$($args[0])/core/lib/include/tree_sitter/api.h"
-
-$env:package = $env:package -replace '\.', '/'
-$env:file = "$($args[1])/generated-sources/jextract/$env:package/TreeSitter.java"
-(Get-Content -path "$env:file").Replace('static final Arena', 'public $0') | Set-Content "$env:file"

scripts/jextract.sh

@@ -2,7 +2,7 @@
 
 package=io.github.treesitter.jtreesitter.internal
 
-jextract \
+exec jextract \
     --include-struct TSInput \
     --include-struct TSInputEdit \
     --include-struct TSLogger \
@@ -182,6 +182,3 @@ jextract \
     -I "$1"/core/lib/include \
     -DTREE_SITTER_HIDE_SYMBOLS \
     "$1"/core/lib/include/tree_sitter/api.h
-
-sed -i'' 's/static final Arena/public &/' \
-    "$2/generated-sources/jextract/${package//.//}/TreeSitter.java"

src/main/java/io/github/treesitter/jtreesitter/Language.java

@@ -2,8 +2,8 @@
 
 import static io.github.treesitter.jtreesitter.internal.TreeSitter.*;
 
-import io.github.treesitter.jtreesitter.internal.TreeSitter;
 import java.lang.foreign.*;
+import java.lang.ref.Cleaner;
 import org.jspecify.annotations.NullMarked;
 import org.jspecify.annotations.Nullable;
 
@@ -28,6 +28,8 @@ public final class Language {
 
     private static final Linker LINKER = Linker.nativeLinker();
 
+    private static final Cleaner CLEANER = Cleaner.create();
+
     private final MemorySegment self;
 
     private final @Unsigned int version;
@@ -40,8 +42,9 @@ public final class Language {
      * @throws IllegalArgumentException If the language version is incompatible.
      */
     public Language(MemorySegment self) throws IllegalArgumentException {
-        this.self = self.reinterpret(LIBRARY_ARENA, TreeSitter::ts_language_delete);
+        this.self = self.asReadOnly();
         version = ts_language_version(this.self);
+        CLEANER.register(self, new Cleanup(this.self));
         if (version < MIN_COMPATIBLE_LANGUAGE_VERSION || version > LANGUAGE_VERSION) {
             throw new IllegalArgumentException(String.format(
                     "Incompatible language version %d. Must be between %d and %d.",
@@ -196,4 +199,17 @@ public int hashCode() {
     public String toString() {
         return "Language{id=0x%x, version=%d}".formatted(self.address(), version);
     }
+
+    private static final class Cleanup implements Runnable {
+        MemorySegment segment;
+
+        private Cleanup(MemorySegment segment) {
+            this.segment = segment;
+        }
+
+        @Override
+        public void run() {
+            ts_language_delete(segment);
+        }
+    }
 }

src/test/java/io/github/treesitter/jtreesitter/languages/TreeSitterJava.java

@@ -1,7 +1,6 @@
 package io.github.treesitter.jtreesitter.languages;
 
 import java.lang.foreign.*;
-import java.lang.invoke.MethodHandle;
 
 public final class TreeSitterJava {
     private static final ValueLayout VOID_PTR =
@@ -39,8 +38,8 @@ private static UnsatisfiedLinkError unresolved(String name) {
     private MemorySegment call(String name) throws UnsatisfiedLinkError {
         var address = symbols.find(name).orElseThrow(() -> unresolved(name));
         try {
-            final MethodHandle function = LINKER.downcallHandle(address, FUNC_DESC);
-            return ((MemorySegment) function.invokeExact()).asReadOnly();
+            var function = LINKER.downcallHandle(address, FUNC_DESC);
+            return (MemorySegment) function.invokeExact();
         } catch (Throwable e) {
             throw new RuntimeException("Call to %s failed".formatted(name), e);
         }