Cleaner completion. Better test coverage

client/README.md

@@ -7,6 +7,17 @@ This extension provides syntax highlighting and code completion for DRL files.
 - Syntax highlighting
 - Code completion
 
+## How to build
+
+Under `client` directory, run:
+
+```bash
+npm install
+npm run pack:dev
+```
+
+vsix file will be generated in `dist` directory.
+
 ## Known Issues
 
 - Code completion may suggest words that are not valid in the current context

drools-completion/pom.xml

@@ -51,5 +51,17 @@
       <scope>test</scope>
     </dependency>
   </dependencies>
-
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>3.2.5</version>
+        <configuration>
+          <argLine>
+            -Djava.util.logging.config.file=${project.basedir}/src/test/resources/logging.properties
+          </argLine>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
 </project>

drools-completion/src/main/java/org/drools/completion/DRLCompletionHelper.java

@@ -15,11 +15,15 @@
  */
 package org.drools.completion;
 
+import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 import com.vmware.antlr4c3.CodeCompletionCore;
+import org.drools.drl.parser.antlr4.DRL10Lexer;
 import org.drools.drl.parser.antlr4.DRL10Parser;
 import org.eclipse.lsp4j.CompletionItem;
 import org.eclipse.lsp4j.CompletionItemKind;
@@ -31,6 +35,15 @@
 
 public class DRLCompletionHelper {
 
+    // PREFERRED_RULES is used to filter out the rules that consist of unwanted tokens
+    // additionally, it can be used to customize getCompletionItems behavior
+    private static final Set<Integer> PREFERRED_RULES = Set.of(
+            DRL10Parser.RULE_drlIdentifier,
+            DRL10Parser.RULE_drlQualifiedName,
+            DRL10Parser.RULE_stringId,
+            DRL10Parser.RULE_consequenceBody
+    );
+
     private DRLCompletionHelper() {
     }
 
@@ -47,11 +60,15 @@ public static List<CompletionItem> getCompletionItems(String text, Position care
     }
 
     static List<CompletionItem> getCompletionItems(DRL10Parser drlParser, int nodeIndex) {
-        CodeCompletionCore core = new CodeCompletionCore(drlParser, null, null);
+        CodeCompletionCore core = new CodeCompletionCore(drlParser, PREFERRED_RULES, Tokens.IGNORED);
         CodeCompletionCore.CandidatesCollection candidates = core.collectCandidates(nodeIndex, null);
 
+        if (candidates.rules.containsKey(DRL10Parser.RULE_consequenceBody)) {
+            // in RHS consequence, parser cannot suggest DRL_RHS_END because of island mode approach, so we add it manually
+            candidates.tokens.put(DRL10Lexer.DRL_RHS_END, List.of());
+        }
+
         return candidates.tokens.keySet().stream().filter(Objects::nonNull)
-                .filter(integer -> !Tokens.IGNORED.contains(integer))
                 .map(integer -> drlParser.getVocabulary().getDisplayName(integer).replace("'", ""))
                 .map(String::toLowerCase)
                 .map(k -> createCompletionItem(k, CompletionItemKind.Keyword))

drools-completion/src/main/java/org/drools/completion/Tokens.java

@@ -24,6 +24,7 @@ public class Tokens {
             DRL10Lexer.MOD_ASSIGN, DRL10Lexer.LSHIFT_ASSIGN, DRL10Lexer.RSHIFT_ASSIGN, DRL10Lexer.URSHIFT_ASSIGN,
             DRL10Lexer.ARROW, DRL10Lexer.COLONCOLON, DRL10Lexer.AT, DRL10Lexer.ELLIPSIS, DRL10Lexer.WS, DRL10Lexer.COMMENT,
             DRL10Lexer.LINE_COMMENT, DRL10Lexer.IDENTIFIER, DRL10Lexer.TEXT,
+            DRL10Lexer.DRL_STRING_LITERAL,
 
             DRL10Lexer.RHS_COMMENT, DRL10Lexer.RHS_LINE_COMMENT, DRL10Lexer.RHS_STRING_LITERAL, DRL10Lexer.RHS_NAMED_CONSEQUENCE_THEN, DRL10Lexer.RHS_CHUNK
     );

drools-completion/src/test/java/org/drools/completion/DRLCompletionHelperTest.java

@@ -5,38 +5,124 @@
 import java.util.concurrent.CompletableFuture;
 
 import org.eclipse.lsp4j.CompletionItem;
-import org.eclipse.lsp4j.CompletionParams;
 import org.eclipse.lsp4j.Diagnostic;
 import org.eclipse.lsp4j.MessageActionItem;
 import org.eclipse.lsp4j.MessageParams;
 import org.eclipse.lsp4j.Position;
 import org.eclipse.lsp4j.PublishDiagnosticsParams;
 import org.eclipse.lsp4j.ShowMessageRequestParams;
-import org.eclipse.lsp4j.TextDocumentIdentifier;
 import org.eclipse.lsp4j.services.LanguageClient;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
 class DRLCompletionHelperTest {
 
-    @Disabled("TBD")
     @Test
     void getCompletionItems() {
-        // TODO
-        String text = "rule MyRule when Dog(name == \"Bart\") then end";
-        CompletionParams completionParams = new CompletionParams();
-        completionParams.setTextDocument(new TextDocumentIdentifier("myDocument"));
+        String text = """
+                package org.example;
+
+                import org.example.model.Dog;
+
+                global java.util.List list;
+
+                rule MyRule
+                  when
+                    $dog : Dog(name == "Bart")
+                  then
+                    list.add($dog.getName());
+                end
+                """;
+
         Position caretPosition = new Position();
+        List<CompletionItem> result;
+
+        // at the beginning of the file
+        caretPosition.setCharacter(0); // caret character(column) position is zero-based
+        caretPosition.setLine(0); // caret line position is zero-based
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).contains("package", "unit"); // once in a file
+        assertThat(completionItemStrings(result)).contains("import", "global", "rule"); // top level statements
+
+        // 'package '
+        caretPosition.setCharacter(8);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(result).isEmpty(); // no completion for identifier
+
+        // 'package org.example;\n\n'
+        caretPosition.setLine(2);
         caretPosition.setCharacter(0);
-        caretPosition.setLine(-1); // -1 needed because of  int row = caretPosition == null ? -1 : caretPosition
-        // .getLine()+1; // caret line position is zero based
-        completionParams.setPosition(caretPosition);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).doesNotContain("package");  // once in a file (already used)
+        assertThat(completionItemStrings(result)).contains("unit"); // once in a file (not yet used)
+        assertThat(completionItemStrings(result)).contains("import", "global", "rule"); // top level statements
+
+        // 'import '
+        caretPosition.setLine(2);
+        caretPosition.setCharacter(7);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).contains("static", "function", "accumulate", "acc"); // 'import static' etc.
+
+        // 'import org.example.model.Dog;\n\n'
+        caretPosition.setLine(4);
+        caretPosition.setCharacter(0);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).doesNotContain("package", "unit");  // should be placed before import
+        assertThat(completionItemStrings(result)).contains("import", "global", "rule"); // top level statements
+
+        // 'global '
+        caretPosition.setLine(4);
+        caretPosition.setCharacter(7);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).contains("boolean", "int"); // types (primitives are not useful, but valid)
+
+        // `rule My`
+        caretPosition.setLine(6);
+        caretPosition.setCharacter(7);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(result).isEmpty(); // no completion for identifier
+
+        // `  wh`
+        caretPosition.setLine(7);
+        caretPosition.setCharacter(3);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).contains("when", "salience"); // inside rule
+
+        // `    $d`
+        caretPosition.setLine(8);
+        caretPosition.setCharacter(6);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).contains("exists", "not"); // inside LHS
+
+        // `    $dog : Dog(`
+        caretPosition.setLine(8);
+        caretPosition.setCharacter(15);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(result).isEmpty(); // no completion for identifier
+
+        // `  th`
+        caretPosition.setLine(9);
+        caretPosition.setCharacter(3);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).doesNotContain("salience"); // attribute is not allowed
+        assertThat(completionItemStrings(result)).contains("then", "exists"); // inside LHS
+
+        // `    li`
+        caretPosition.setLine(10);
+        caretPosition.setCharacter(6);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).contains("end"); // inside RHS
+
+        // at the end of the file
+        caretPosition.setLine(12);
+        caretPosition.setCharacter(0);
+        result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
+        assertThat(completionItemStrings(result)).contains("import", "global", "rule"); // top level statements
+    }
 
-        List<CompletionItem> result = DRLCompletionHelper.getCompletionItems(text, caretPosition, getLanguageClient());
-        CompletionItem completionItem = result.get(0);
-        assertThat(completionItem.getInsertText()).isEqualTo("suggestion");
+    private List<String> completionItemStrings(List<CompletionItem> result) {
+        return result.stream().map(CompletionItem::getInsertText).toList();
     }
 
     private LanguageClient getLanguageClient() {

drools-completion/src/test/resources/logging.properties

@@ -0,0 +1,8 @@
+handlers = java.util.logging.ConsoleHandler
+
+java.util.logging.ConsoleHandler.level = FINE
+java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter
+
+# To debug CodeCompletionCore
+#com.vmware.antlr4c3.CodeCompletionCore.level = FINE
+