Add tests for revisions/current/test.submit_rule and fix subtle bug

This commit adds two tests for verifying that the input provided to
test.submit_rule makes it's way into RulesEvaluator and returns a
meaningful response.

This commit fixes a subtle bug that would make it so that we don't pass
the input to the evaluator if the project has not set up any Prolog rule
before.

Change-Id: I25445abccb02a72995abc289d169699fac2536ba

java/com/google/gerrit/extensions/common/TestSubmitRuleInfo.java

@@ -14,7 +14,9 @@
 
 package com.google.gerrit.extensions.common;
 
+import com.google.common.base.MoreObjects;
 import java.util.Map;
+import java.util.Objects;
 
 public class TestSubmitRuleInfo {
   /** @see com.google.gerrit.common.data.SubmitRecord.Status */
@@ -32,4 +34,37 @@ public class TestSubmitRuleInfo {
 
     public static None INSTANCE = new None();
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof TestSubmitRuleInfo) {
+      TestSubmitRuleInfo other = (TestSubmitRuleInfo) o;
+      return Objects.equals(status, other.status)
+          && Objects.equals(errorMessage, other.errorMessage)
+          && Objects.equals(ok, other.ok)
+          && Objects.equals(reject, other.reject)
+          && Objects.equals(need, other.need)
+          && Objects.equals(may, other.may)
+          && Objects.equals(impossible, other.impossible);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(status, errorMessage, ok, reject, need, may, impossible);
+  }
+
+  @Override
+  public String toString() {
+    return MoreObjects.toStringHelper(this)
+        .add("status", status)
+        .add("errorMessage", errorMessage)
+        .add("ok", ok)
+        .add("reject", reject)
+        .add("need", need)
+        .add("may", may)
+        .add("impossible", impossible)
+        .toString();
+  }
 }

java/com/google/gerrit/server/rules/PrologRule.java

@@ -39,8 +39,8 @@ public class PrologRule implements SubmitRule {
   @Override
   public Collection<SubmitRecord> evaluate(ChangeData cd, SubmitRuleOptions opts) {
     ProjectState projectState = projectCache.get(cd.project());
-    // We only want to run the prolog engine if we have at least one rules.pl file to use.
-    if (projectState == null || !projectState.hasPrologRules()) {
+    // We only want to run the Prolog engine if we have at least one rules.pl file to use.
+    if ((projectState == null || !projectState.hasPrologRules()) && opts.rule() == null) {
       return Collections.emptyList();
     }
 

javatests/com/google/gerrit/acceptance/api/change/SubmitTypeRuleIT.java

@@ -23,12 +23,14 @@ import static com.google.gerrit.extensions.client.SubmitType.REBASE_ALWAYS;
 import static com.google.gerrit.extensions.client.SubmitType.REBASE_IF_NECESSARY;
 
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.extensions.api.changes.ReviewInput;
 import com.google.gerrit.extensions.api.projects.BranchInput;
 import com.google.gerrit.extensions.client.SubmitType;
+import com.google.gerrit.extensions.common.TestSubmitRuleInfo;
 import com.google.gerrit.extensions.common.TestSubmitRuleInput;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.RestApiException;
@@ -255,6 +257,43 @@ public class SubmitTypeRuleIT extends AbstractDaemonTest {
     }
   }
 
+  @Test
+  public void invalidSubmitRuleWithNoRulesInProject() throws Exception {
+    String changeId = createChange("master", "change 1").getChangeId();
+
+    TestSubmitRuleInput in = new TestSubmitRuleInput();
+    in.rule = "invalid prolog rule";
+    // We have no rules.pl by default. The fact that the default rules are showing up here is a bug.
+    List<TestSubmitRuleInfo> response = gApi.changes().id(changeId).current().testSubmitRule(in);
+    assertThat(response).containsExactly(defaultUnsatisfiedRuleInfo(), invalidPrologRuleInfo());
+  }
+
+  @Test
+  public void invalidSubmitRuleWithRulesInProject() throws Exception {
+    setRulesPl(SUBMIT_TYPE_FROM_SUBJECT);
+
+    String changeId = createChange("master", "change 1").getChangeId();
+
+    TestSubmitRuleInput in = new TestSubmitRuleInput();
+    in.rule = "invalid prolog rule";
+    List<TestSubmitRuleInfo> response = gApi.changes().id(changeId).current().testSubmitRule(in);
+    assertThat(response).containsExactly(invalidPrologRuleInfo());
+  }
+
+  private static TestSubmitRuleInfo invalidPrologRuleInfo() {
+    TestSubmitRuleInfo info = new TestSubmitRuleInfo();
+    info.status = "RULE_ERROR";
+    info.errorMessage = "operator expected after expression at: invalid prolog rule end_of_file.";
+    return info;
+  }
+
+  private static TestSubmitRuleInfo defaultUnsatisfiedRuleInfo() {
+    TestSubmitRuleInfo info = new TestSubmitRuleInfo();
+    info.status = "NOT_READY";
+    info.need = ImmutableMap.of("Code-Review", TestSubmitRuleInfo.None.INSTANCE);
+    return info;
+  }
+
   private List<RevCommit> log(String commitish, int n) throws Exception {
     try (Repository repo = repoManager.openRepository(project);
         Git git = new Git(repo)) {