[DO-NOT-MERGE][WIP][incubator-kie-drools-6220] Slim down DRL syntax with New Antlr4 Parser

.github/workflows/pr-downstream.yml

@@ -33,6 +33,7 @@ on:
 
 jobs:
   kogito-downstream-build:
+    if: false
     concurrency:
       group: pr-${{ matrix.job_name }}_${{ matrix.os }}_${{ matrix.java-version }}_${{ matrix.maven-version }}_${{ github.head_ref }}
       cancel-in-progress: true

.github/workflows/pr-drools.yml

@@ -61,7 +61,7 @@ jobs:
       - name: Build Chain
         uses: apache/incubator-kie-kogito-pipelines/.ci/actions/build-chain@main
         env:
-          BUILD_MVN_OPTS_CURRENT: '-Dfull -Dreproducible'
+          BUILD_MVN_OPTS_CURRENT: '-Dfull -Dreproducible -DenableNewParser'
           MAVEN_OPTS: "-Dfile.encoding=UTF-8"
         with:
           definition-file: https://raw.githubusercontent.com/${GROUP:apache}/incubator-kie-kogito-pipelines/${BRANCH:main}/.ci/pull-request-config.yaml

.gitignore

@@ -29,6 +29,7 @@ nbproject
 *.ipr
 *.iws
 *.iml
+build.log
 
 # generated files
 dependency-reduced-pom.xml

drools-drl/drools-drl-ast/src/main/java/org/drools/drl/ast/descr/OperatorDescr.java

@@ -26,6 +26,9 @@
 public class OperatorDescr extends BaseDescr {
     private static final long serialVersionUID = 520l;
 
+    // prefix for custom operators which are not built-in
+    public static final String CUSTOM_OPERATOR_PREFIX = "##";
+
     private String            operator;
     private boolean           negated;
     private List<String>      parameters;
@@ -55,7 +58,15 @@ public String getOperator() {
     }
 
     public void setOperator( String operator ) {
-        this.operator = operator != null ? operator.trim() : null;
+        this.operator = operator != null ? trimOperator(operator) : null;
+    }
+
+    private String trimOperator(String operator) {
+        operator = operator.trim();
+        if (operator.startsWith(CUSTOM_OPERATOR_PREFIX)) {
+            operator = operator.substring(CUSTOM_OPERATOR_PREFIX.length());
+        }
+        return operator;
     }
 
     public boolean isNegated() {

drools-drl/drools-drl-parser-tests/src/test/java/org/drools/drl/parser/antlr4/DRLParserTest.java → drools-drl/drools-drl-parser-tests/src/test/java/org/drools/drl/parser/antlr4/DRL10ParserTest.java

@@ -31,14 +31,14 @@
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.drools.drl.parser.antlr4.DRLParserHelper.computeTokenIndex;
-import static org.drools.drl.parser.antlr4.DRLParserHelper.createDrlParser;
-import static org.drools.drl.parser.antlr4.DRLParserHelper.parse;
+import static org.drools.drl.parser.antlr4.DRL10ParserHelper.computeTokenIndex;
+import static org.drools.drl.parser.antlr4.DRL10ParserHelper.createDrlParser;
+import static org.drools.drl.parser.antlr4.DRL10ParserHelper.parse;
 
 /**
  * This test class is specific to new antlr4 parser.
  */
-class DRLParserTest {
+class DRL10ParserTest {
 
     private static final String drl =
             "package org.test;\n" +
@@ -94,7 +94,7 @@ void parse_basicRule() {
 
     @Test
     void computeTokenIndex_basicRule() {
-        DRLParser parser = createDrlParser(drl);
+        DRL10Parser parser = createDrlParser(drl);
         parser.compilationUnit();
 
         assertThat((int) computeTokenIndex(parser, 1, 0)).isEqualTo(0);

drools-drl/drools-drl-parser-tests/src/test/java/org/drools/drl/parser/antlr4/DRLExprParserTest.java

@@ -27,7 +27,6 @@
 import org.drools.drl.ast.descr.ConstraintConnectiveDescr;
 import org.drools.drl.ast.descr.RelationalExprDescr;
 import org.drools.drl.parser.DrlExprParser;
-import org.drools.drl.parser.DrlExprParserFactory;
 import org.drools.drl.parser.DrlParser;
 import org.drools.drl.parser.DroolsParserException;
 import org.drools.drl.parser.impl.Operator;
@@ -38,7 +37,6 @@
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.EnumSource;
 import org.junit.jupiter.params.provider.ValueSource;
-import org.kie.internal.builder.conf.LanguageLevelOption;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assumptions.assumeFalse;
@@ -52,7 +50,7 @@ class DRLExprParserTest {
 
     @BeforeEach
     void setUp() {
-        this.parser = DrlExprParserFactory.getDrlExprParser(LanguageLevelOption.DRL6);
+        this.parser = ParserTestUtils.getExprParser();
     }
 
     @AfterEach
@@ -175,7 +173,7 @@ void bindingConstraint() {
 
     @Test
     void bindingWithRestrictions() {
-        String source = "$x : property > value && < 20";
+        String source = "$x : property > value && property < 20";
         ConstraintConnectiveDescr result = parser.parse( source );
         assertThat(parser.hasErrors()).as(parser.getErrors().toString()).isFalse();
 
@@ -458,7 +456,7 @@ void noViableAlt() {
             assertThat(exception.getColumn()).isEqualTo(2);
             assertThat(exception.getOffset()).isEqualTo(2);
             assertThat(exception.getMessage())
-                    .isEqualToIgnoringCase("[ERR 101] Line 1:2 no viable alternative at input 'a'");
+                    .isEqualToIgnoringCase("[ERR 101] Line 1:2 no viable alternative at input '~a'");
         } else {
             assertThat(parser.hasErrors()).isFalse();
         }

drools-drl/drools-drl-parser-tests/src/test/java/org/drools/drl/parser/antlr4/DescrCommonPropertyTest.java

@@ -245,7 +245,7 @@ void typeFieldDescr() {
     void attributeDescr() {
         final String source = "rule R1\n" +
                 "  salience 42\n" +
-                "  agenda-group \"my_group\"\n" +
+                "  ruleflow-group \"my_group\"\n" +
                 "  when\n" +
                 "  then\n" +
                 "end";
@@ -257,10 +257,10 @@ void attributeDescr() {
         //   Backward compatibility doesn't seem to be required in this case. (If do it, the code would be unnecessarily complicated.)
         if (DrlParser.ANTLR4_PARSER_ENABLED) {
             assertProperties(rule.getAttributes().get("salience"), 10, 21, 2, 2, 2, 12);
-            assertProperties(rule.getAttributes().get("agenda-group"), 24, 47, 3, 2, 3, 24);
+            assertProperties(rule.getAttributes().get("ruleflow-group"), 24, 49, 3, 2, 3, 26);
         } else {
             assertProperties(rule.getAttributes().get("salience"), 19, 21, 2, 11, 2, 12);
-            assertProperties(rule.getAttributes().get("agenda-group"), 37, 47, 3, 15, 3, 24);
+            assertProperties(rule.getAttributes().get("ruleflow-group"), 39, 49, 3, 17, 3, 26);
         }
     }
 

drools-drl/drools-drl-parser-tests/src/test/java/org/drools/drl/parser/antlr4/DescrDumperTest.java

@@ -24,13 +24,12 @@
 import org.drools.drl.ast.descr.BindingDescr;
 import org.drools.drl.ast.descr.ConstraintConnectiveDescr;
 import org.drools.drl.parser.DrlExprParser;
-import org.drools.drl.parser.DrlExprParserFactory;
 import org.drools.mvel.evaluators.MatchesEvaluatorsDefinition;
 import org.drools.mvel.evaluators.SetEvaluatorsDefinition;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
-import org.kie.internal.builder.conf.LanguageLevelOption;
+import org.junit.jupiter.api.condition.DisabledIfSystemProperty;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -47,6 +46,7 @@ void setUp() {
         dumper = new DescrDumper();
     }
 
+    @DisabledIfSystemProperty(named = "drools.drl.antlr4.parser.enabled", matches = "true")
     @Test
     void dump() {
         String input = "price > 10 && < 20 || == $val || == 30";
@@ -147,6 +147,7 @@ void dumpWithDateAttr() {
         assertThat(result).isEqualTo(expected);
     }
 
+    @DisabledIfSystemProperty(named = "drools.drl.antlr4.parser.enabled", matches = "true")
     @Test
     void dumpComplex() {
         String input = "a ( > 60 && < 70 ) || ( > 50 && < 55 ) && a3 == \"black\" || a == 40 && a3 == \"pink\" || a == 12 && a3 == \"yellow\" || a3 == \"blue\"";
@@ -220,6 +221,7 @@ void dumpBindings4() {
         assertThat(result).isEqualTo(expected);
     }
 
+    @DisabledIfSystemProperty(named = "drools.drl.antlr4.parser.enabled", matches = "true")
     @Test
     void dumpBindingsWithRestriction() {
         String input = "$x : age > 10 && < 20 || > 30";
@@ -360,7 +362,7 @@ void processImplicitConstraints() {
     }
 
     public ConstraintConnectiveDescr parse(final String constraint) {
-        DrlExprParser parser = DrlExprParserFactory.getDrlExprParser(LanguageLevelOption.DRL6);
+        DrlExprParser parser = ParserTestUtils.getExprParser();
         ConstraintConnectiveDescr result = parser.parse(constraint);
         assertThat(parser.hasErrors()).as(parser.getErrors().toString()).isFalse();