Test that plugin section in project.config is unset if all plugin configs are empty

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I2bd14319046ab1cd9e1480f44e9eda5341a3969a
diff --git a/javatests/com/google/gerrit/server/project/ProjectConfigTest.java b/javatests/com/google/gerrit/server/project/ProjectConfigTest.java
index 75e1cd7..07cfe2f 100644
--- a/javatests/com/google/gerrit/server/project/ProjectConfigTest.java
+++ b/javatests/com/google/gerrit/server/project/ProjectConfigTest.java
@@ -454,6 +454,27 @@
   }
 
   @Test
+  public void pluginSectionIsUnsetIfAllPluginConfigsAreEmpty() throws Exception {
+    RevCommit rev =
+        tr.commit()
+            .add(
+                "project.config",
+                "[commentlink \"bugzilla\"]\n"
+                    + "  match = \"(bugs#?)(d+)\"\n"
+                    + "[plugin \"somePlugin\"]\n"
+                    + "  key = value\n")
+            .create();
+    update(rev);
+
+    ProjectConfig cfg = read(rev);
+    PluginConfig pluginCfg = cfg.getPluginConfig("somePlugin");
+    pluginCfg.unset("key");
+    rev = commit(cfg);
+    assertThat(text(rev, "project.config"))
+        .isEqualTo("[commentlink \"bugzilla\"]\n  match = \"(bugs#?)(d+)\"\n");
+  }
+
+  @Test
   public void readPluginConfigGroupReference() throws Exception {
     RevCommit rev =
         tr.commit()