diff --git a/src/main/java/com/github/_1c_syntax/utils/Lazy.java b/src/main/java/com/github/_1c_syntax/utils/Lazy.java
index f37a1bc..613bba1 100644
--- a/src/main/java/com/github/_1c_syntax/utils/Lazy.java
+++ b/src/main/java/com/github/_1c_syntax/utils/Lazy.java
@@ -56,9 +56,11 @@ public T getOrCompute(Supplier<T> supplier) {
     final T result = value; // Just one volatile read
     if (result == null) {
       lock.lock();
-      var localResult = maybeCompute(supplier);
-      lock.unlock();
-      return localResult;
+      try {
+        return maybeCompute(supplier);
+      } finally {
+        lock.unlock();
+      }
     }
     return result;
   }
diff --git a/src/test/java/com/github/_1c_syntax/utils/LazyTest.java b/src/test/java/com/github/_1c_syntax/utils/LazyTest.java
new file mode 100644
index 0000000..d5c6e7f
--- /dev/null
+++ b/src/test/java/com/github/_1c_syntax/utils/LazyTest.java
@@ -0,0 +1,113 @@
+/*
+ * This file is a part of 1c-syntax utils.
+ *
+ * Copyright (c) 2018-2026
+ * Alexey Sosnoviy <labotamy@gmail.com>, Nikita Fedkin <nixel2007@gmail.com> and contributors
+ *
+ * SPDX-License-Identifier: LGPL-3.0-or-later
+ *
+ * 1c-syntax utils is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3.0 of the License, or (at your option) any later version.
+ *
+ * 1c-syntax utils is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with 1c-syntax utils.
+ */
+package com.github._1c_syntax.utils;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.concurrent.locks.ReentrantLock;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class LazyTest {
+
+  @Test
+  void getOrComputeReturnsValue() {
+    var lazy = new Lazy<>(() -> "value");
+    assertThat(lazy.getOrCompute()).isEqualTo("value");
+    assertThat(lazy.isPresent()).isTrue();
+  }
+
+  @Test
+  void getOrComputeCachesValue() {
+    var counter = new int[]{0};
+    var lazy = new Lazy<>(() -> {
+      counter[0]++;
+      return "value";
+    });
+    lazy.getOrCompute();
+    lazy.getOrCompute();
+    lazy.getOrCompute();
+    assertThat(counter[0]).isEqualTo(1);
+  }
+
+  @Test
+  void supplierExceptionReleasesLock() {
+    // Регрессия: до фикса unlock() стоял после maybeCompute() без try/finally,
+    // и любое RuntimeException из supplier'а оставляло lock захваченным
+    // навсегда — следующий поток вешал getOrCompute() либо документ-сервис
+    // (где Lazy шарит lock с externalным ReentrantLock).
+    var lock = new ReentrantLock();
+    var lazy = new Lazy<String>(() -> {
+      throw new IllegalStateException("boom");
+    }, lock);
+
+    assertThatThrownBy(lazy::getOrCompute).isInstanceOf(IllegalStateException.class);
+    assertThat(lock.isLocked())
+      .as("lock должен быть отпущен после RuntimeException в supplier'е")
+      .isFalse();
+    assertThat(lock.getHoldCount()).isZero();
+  }
+
+  @Test
+  void supplierExceptionReleasesSharedLockMultipleAttempts() {
+    // Дважды бросаем, потом успешно вычисляем — lock должен корректно
+    // освобождаться каждый раз, и финальный getOrCompute должен пройти.
+    var lock = new ReentrantLock();
+    var attempt = new int[]{0};
+    var lazy = new Lazy<String>(() -> {
+      attempt[0]++;
+      if (attempt[0] < 3) {
+        throw new IllegalStateException("attempt " + attempt[0]);
+      }
+      return "ok";
+    }, lock);
+
+    assertThatThrownBy(lazy::getOrCompute).isInstanceOf(IllegalStateException.class);
+    assertThat(lock.isLocked()).isFalse();
+    assertThatThrownBy(lazy::getOrCompute).isInstanceOf(IllegalStateException.class);
+    assertThat(lock.isLocked()).isFalse();
+    assertThat(lazy.getOrCompute()).isEqualTo("ok");
+    assertThat(lock.isLocked()).isFalse();
+  }
+
+  @Test
+  void clearAllowsRecompute() {
+    var counter = new int[]{0};
+    var lazy = new Lazy<>(() -> {
+      counter[0]++;
+      return "v" + counter[0];
+    });
+    assertThat(lazy.getOrCompute()).isEqualTo("v1");
+    lazy.clear();
+    assertThat(lazy.isPresent()).isFalse();
+    assertThat(lazy.getOrCompute()).isEqualTo("v2");
+  }
+
+  @Test
+  void getReturnsNullBeforeCompute() {
+    var lazy = new Lazy<>(() -> "value");
+    assertThat(lazy.get()).isNull();
+    lazy.getOrCompute();
+    assertThat(lazy.get()).isEqualTo("value");
+  }
+}