Merge pull request #1855 from bibonix/fix-1072-event-commit-id

#1072: add Event.Smart#commitId()

Author: yegor256

src/main/java/com/jcabi/github/Event.java

@@ -226,6 +226,18 @@ public Date createdAt() throws IOException {
             }
         }
 
+        /**
+         * SHA of the commit referenced by this event (if any).
+         * @return SHA of the commit, or absent if not associated with one
+         * @throws IOException If there is any I/O problem
+         * @since 1.7.0
+         */
+        public Optional<String> commitId() throws IOException {
+            return Optional.fromNullable(
+                this.event.json().getString("commit_id", null)
+            );
+        }
+
         /**
          * Label that was added or removed in this event (if any).
          * @return Label that was added or removed

src/test/java/com/jcabi/github/EventTest.java

@@ -0,0 +1,79 @@
+/*
+ * SPDX-FileCopyrightText: Copyright (c) 2013-2026 Yegor Bugayenko
+ * SPDX-License-Identifier: MIT
+ */
+package com.jcabi.github;
+
+import com.google.common.base.Optional;
+import jakarta.json.Json;
+import jakarta.json.JsonObject;
+import jakarta.json.JsonValue;
+import java.io.IOException;
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.Matchers;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+
+/**
+ * Test case for {@link Event.Smart}.
+ * @since 1.7.0
+ */
+final class EventTest {
+
+    @Test
+    void readsCommitIdWhenPresent() throws IOException {
+        final String sha = "6dcb09b5b57875f334f61aebed695e2e4193db51";
+        MatcherAssert.assertThat(
+            "Commit SHA is not equal",
+            new Event.Smart(
+                EventTest.eventWithJson(
+                    Json.createObjectBuilder()
+                        .add("commit_id", sha)
+                        .build()
+                )
+            ).commitId(),
+            Matchers.equalTo(Optional.of(sha))
+        );
+    }
+
+    @Test
+    void commitIdIsAbsentWhenJsonNull() throws IOException {
+        MatcherAssert.assertThat(
+            "Commit ID should be absent when JSON value is null",
+            new Event.Smart(
+                EventTest.eventWithJson(
+                    Json.createObjectBuilder()
+                        .add("commit_id", JsonValue.NULL)
+                        .build()
+                )
+            ).commitId(),
+            Matchers.equalTo(Optional.<String>absent())
+        );
+    }
+
+    @Test
+    void commitIdIsAbsentWhenMissing() throws IOException {
+        MatcherAssert.assertThat(
+            "Commit ID should be absent when key is missing",
+            new Event.Smart(
+                EventTest.eventWithJson(
+                    Json.createObjectBuilder().build()
+                )
+            ).commitId(),
+            Matchers.equalTo(Optional.<String>absent())
+        );
+    }
+
+    /**
+     * Build an Event whose json() method returns the given object.
+     * @param obj JSON object to expose via Event.json()
+     * @return Mocked Event
+     * @throws IOException If stubbing fails
+     */
+    private static Event eventWithJson(final JsonObject obj)
+        throws IOException {
+        final Event event = Mockito.mock(Event.class);
+        Mockito.doReturn(obj).when(event).json();
+        return event;
+    }
+}