Refactoring

expression-components/main/ui/controllers/FormulaEvaluatorUiController.cls

@@ -14,8 +14,7 @@ public with sharing class FormulaEvaluatorUiController {
     @AuraEnabled(Cacheable=true)
     public static Object evaluate(String recordId, String formula, Boolean respectSharing) {
         try {
-            Evaluator.Config config = new Evaluator.Config();
-            config.sharing = respectSharing ? Evaluator.SharingMode.WITH : Evaluator.SharingMode.WITHOUT;
+            Configuration config = new Configuration().respectSharing(respectSharing);
             if (String.isBlank(recordId)) {
                 return Evaluator.run(formula, config);
             } else {

expression-src/main/api/Configuration.cls

@@ -0,0 +1,43 @@
+global with sharing class Configuration {
+    public static Configuration.SharingMode evaluationSharingMode;
+
+    global enum SharingMode {
+        WITH,
+        WITHOUT
+    }
+
+    global SharingMode sharing = SharingMode.WITH;
+    global Boolean printAst = false;
+    public Boolean withDiagnostics = false;
+
+    global Configuration respectSharing(Boolean respect) {
+        sharing = respect ? SharingMode.WITH : SharingMode.WITHOUT;
+        return this;
+    }
+
+    global Configuration printAst() {
+        printAst = true;
+        return this;
+    }
+
+    global Configuration withDiagnostics() {
+        withDiagnostics = true;
+        return this;
+    }
+
+    public void subscribe(EvaluatorEventNotifier notifier) {
+        // Always subscribe to the event that sets the sharing mode
+        // at the beginning of the evaluation regardless of configuration.
+        notifier.subscribe(OnEvaluationStartEvent.class, new EvaluationSharingModeSetter());
+
+        if (this.printAst) {
+            notifier.subscribe(OnAfterParseEvent.class, new AstPrinter());
+        }
+
+        if (this.withDiagnostics) {
+            EvaluationDiagnosticsListener diagnosticsListener = new EvaluationDiagnosticsListener();
+            notifier.subscribe(OnEvaluationStartEvent.class, diagnosticsListener);
+            notifier.subscribe(OnEvaluationEndEvent.class, diagnosticsListener);
+        }
+    }
+}

expression-src/main/api/EvaluationResult.cls

@@ -0,0 +1,10 @@
+global with sharing class EvaluationResult {
+    global Object result { get; private set; }
+
+    public Map<String, Object> additionalData { get; private set; }
+
+    public EvaluationResult(Object result, Map<String, Object> additionalData) {
+        this.result = result;
+        this.additionalData = additionalData;
+    }
+}

expression-src/main/api/Evaluator.cls

@@ -1,16 +1,14 @@
 /**
  * @description Evaluates a formula and returns the result.
  */
-global with sharing class Evaluator {
-    public static SharingMode evaluationSharingMode;
-
+global with sharing abstract class Evaluator {
     /**
      * @description Evaluates a formula and returns the result.
      * @param formula The formula to evaluate.
      * @return The result of the formula.
      */
     global static Object run(String formula) {
-        return run(formula, new Config());
+        return run(formula, new Configuration());
     }
 
     /**
@@ -20,7 +18,7 @@ global with sharing class Evaluator {
      *        the evaluation.
      * @return The result of the formula.
      */
-    global static Object run(String formula, Config config) {
+    global static Object run(String formula, Configuration config) {
         return run(formula, (SObject) null, config);
     }
 
@@ -33,7 +31,7 @@ global with sharing class Evaluator {
      * @return The result of the formula.
      */
     global static Object run(String formula, SObject context) {
-        return run(formula, context, new Config());
+        return run(formula, context, new Configuration());
     }
 
     /**
@@ -46,9 +44,8 @@ global with sharing class Evaluator {
      *        the evaluation.
      * @return The result of the formula.
      */
-    global static Object run(String formula, SObject context, Config config) {
-        Expr pipedExpression = parseExpression(formula, config);
-        return interpretWithContext(context, pipedExpression, config);
+    global static Object run(String formula, SObject context, Configuration config) {
+        return EvaluatorResolver.forRecord(context).evaluate(formula, config).result;
     }
 
     /**
@@ -60,7 +57,7 @@ global with sharing class Evaluator {
      * @return The result of the formula.
      */
     global static Object run(String formula, Id recordId) {
-        return run(formula, recordId, new Config());
+        return run(formula, recordId, new Configuration());
     }
 
     /**
@@ -73,58 +70,7 @@ global with sharing class Evaluator {
      *        the evaluation.
      * @return The result of the formula.
      */
-    global static Object run(String formula, Id recordId, Config config) {
-        Expr pipedExpression = parseExpression(formula, config);
-        SObject record = getRecord(recordId, pipedExpression);
-        return interpretWithContext(record, pipedExpression, config);
-    }
-
-    private static Expr parseExpression(String formula, Config config) {
-        evaluationSharingMode = config.sharing;
-        Scanner scanner = new Scanner(formula);
-        List<Token> tokens = scanner.scanTokens();
-
-        Parser parser = new Parser(tokens);
-        Expr expression = parser.parse();
-
-        if (config.printAst) {
-            AstPrinter printer = new AstPrinter();
-            printer.printAst(expression);
-        }
-
-        PipeResolver pipeInterpreter = new PipeResolver();
-        Expr pipedExpression = pipeInterpreter.resolve(expression);
-        return pipedExpression;
-    }
-
-    private static SObject getRecord(Id recordId, Expr pipedExpression) {
-        ContextResolver ctxInterpreter = new ContextResolver(recordId);
-        return ctxInterpreter.build(pipedExpression);
-    }
-
-    private static Object interpretWithContext(SObject record, Expr pipedExpression, Config config) {
-        Environment env = new Environment(record);
-        IInterpreter interpreter = getInterpreter(env, config);
-        return interpreter.interpret(pipedExpression);
-    }
-
-    global enum SharingMode {
-        WITH,
-        WITHOUT
-    }
-
-    global class Config {
-        global SharingMode sharing = SharingMode.WITH;
-        global Boolean printAst = false;
-        public Boolean withDiagnostics = false;
-    }
-
-    private static IInterpreter getInterpreter(Environment env, Config config) {
-        IInterpreter mainInterpreter = new Interpreter(env);
-        if (config.withDiagnostics) {
-            return new DiagnosticsDecorator(mainInterpreter);
-        } else {
-            return mainInterpreter;
-        }
+    global static Object run(String formula, Id recordId, Configuration config) {
+        return EvaluatorResolver.forId(recordId).evaluate(formula, config).result;
     }
 }

expression-src/main/editor/controllers/PlaygroundController.cls

@@ -36,14 +36,20 @@ public with sharing class PlaygroundController {
     @AuraEnabled
     public static Result validate(String expr, Id recordId) {
         Result toReturn = new Result();
-        Evaluator.Config config = new Evaluator.Config();
-        config.withDiagnostics = true;
+        Configuration config = new Configuration().withDiagnostics().printAst();
         try {
+            EvaluationResult evalResult;
             if (String.isNotBlank(recordId)) {
-                toReturn.result = Evaluator.run(expr, recordId, config);
+                evalResult = EvaluatorResolver.forId(recordId).evaluate(expr, config);
             } else {
-                toReturn.result = Evaluator.run(expr, config);
+                evalResult = EvaluatorResolver.withoutContext().evaluate(expr, config);
             }
+
+            toReturn.result = evalResult.result;
+            EvaluationDiagnosticsListener.DiagnosticsResult diagnosticsResult =
+                (EvaluationDiagnosticsListener.DiagnosticsResult)evalResult.additionalData.get('diagnostics');
+            toReturn.diagnostics = new Diagnostics(diagnosticsResult);
+            toReturn.ast = evalResult.additionalData.get('ast');
         } catch (Exceptions.PositionAwareException e) {
             EvaluationError error = new EvaluationError();
             error.message = e.getMessage();
@@ -60,8 +66,6 @@ public with sharing class PlaygroundController {
             toReturn.error = error;
         }
 
-        toReturn.diagnostics = new Diagnostics(DiagnosticsDecorator.result);
-
         return toReturn;
     }
 
@@ -74,6 +78,9 @@ public with sharing class PlaygroundController {
 
         @AuraEnabled
         public Diagnostics diagnostics;
+
+        @AuraEnabled
+        public Object ast;
     }
 
     public class Diagnostics {
@@ -89,7 +96,7 @@ public with sharing class PlaygroundController {
         @AuraEnabled
         public Integer queryRows;
 
-        public Diagnostics(DiagnosticsDecorator.DiagnosticsResult result) {
+        public Diagnostics(EvaluationDiagnosticsListener.DiagnosticsResult result) {
             this.cpuTime = result?.cpuTime;
             this.dmlStatements = result?.dmlStatements;
             this.queries = result?.queries;

expression-src/main/editor/lwc/playground/playground.html

@@ -47,6 +47,12 @@
                                         <li><strong>Query Rows:</strong> {diagnostics.queryRows}</li>
                                     </ul>
                                 </lightning-tab>
+                                <lightning-tab label="AST">
+                                    <pre class={resultColor}>
+                                        <lightning-formatted-rich-text
+                                                value={ast}></lightning-formatted-rich-text>
+                                    </pre>
+                                </lightning-tab>
                             </lightning-tabset>
                         </div>
                     </div>

expression-src/main/editor/lwc/playground/playground.js

@@ -8,6 +8,7 @@ export default class Monaco extends LightningElement {
   iframeUrl = `${monaco}/main.html`;
   result = {};
   diagnostics = {};
+  ast = {};
 
   async iframeLoaded() {
     const functionKeywords = await getFunctions();
@@ -41,6 +42,7 @@ export default class Monaco extends LightningElement {
     }
 
     this.diagnostics = result.diagnostics;
+    this.ast = this._syntaxHighlight(JSON.stringify(result.ast, null, 4));
   }
 
   handleInputChange(event) {

expression-src/main/src/helpers/QRunner.cls

@@ -7,7 +7,7 @@ public inherited sharing abstract class QRunner {
             return mockRunner;
         }
 
-        if (Evaluator.evaluationSharingMode == Evaluator.SharingMode.WITH) {
+        if (Configuration.evaluationSharingMode == Configuration.SharingMode.WITH) {
             return new WithSharingRunner();
         } else {
             return new WithoutSharingRunner();

expression-src/main/src/interpreter/tests/DiagnosticsDecoratorTest.cls

@@ -1,17 +1,19 @@
+// TODO: Rename and move to a more appropriate location
 @IsTest
 private class DiagnosticsDecoratorTest {
     @IsTest
     static void populatesDiagnosticsWhenRun() {
         String expression = '1 + 2';
-        Evaluator.Config configWithDiagnostics = new Evaluator.Config();
-        configWithDiagnostics.withDiagnostics = true;
+        Configuration configWithDiagnostics = new Configuration().withDiagnostics();
+        EvaluationResult result = EvaluatorResolver.withoutContext().evaluate(expression, configWithDiagnostics);
 
-        Object result = Evaluator.run(expression, configWithDiagnostics);
+        Assert.isNotNull(result.additionalData.get('diagnostics'));
 
-        Assert.areEqual(3, result);
-        Assert.isNotNull(DiagnosticsDecorator.result.cpuTime);
-        Assert.isNotNull(DiagnosticsDecorator.result.dmlStatements);
-        Assert.isNotNull(DiagnosticsDecorator.result.queries);
-        Assert.isNotNull(DiagnosticsDecorator.result.queryRows);
+        EvaluationDiagnosticsListener.DiagnosticsResult diagnostics =
+            (EvaluationDiagnosticsListener.DiagnosticsResult) result.additionalData.get('diagnostics');
+        Assert.isNotNull(diagnostics.cpuTime);
+        Assert.isNotNull(diagnostics.dmlStatements);
+        Assert.isNotNull(diagnostics.queries);
+        Assert.isNotNull(diagnostics.queryRows);
     }
 }

expression-src/main/src/resolver/EvaluatorEventListener.cls

@@ -0,0 +1,3 @@
+public interface EvaluatorEventListener {
+    Map<String, Object> handle(EvaluatorEvent event);
+}

expression-src/main/src/resolver/EvaluatorEventListener.cls-meta.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ApexClass xmlns="http://soap.sforce.com/2006/04/metadata">
+    <apiVersion>58.0</apiVersion>
+    <status>Active</status>
+</ApexClass>

expression-src/main/src/resolver/EvaluatorEventNotifier.cls

@@ -0,0 +1,33 @@
+public with sharing class EvaluatorEventNotifier {
+    final Map<Type, List<EvaluatorEventListener>> listeners =
+        new Map<Type, List<EvaluatorEventListener>>();
+
+    // Holds any data received from the event handler.
+    final Map<String, Object> listenerData;
+
+    public EvaluatorEventNotifier(Map<String, Object> listenerData) {
+        this.listenerData = listenerData;
+    }
+
+    public void subscribe(Type eventType, EvaluatorEventListener listener) {
+        List<EvaluatorEventListener> users = listeners.get(eventType);
+        if (users == null) {
+            users = new List<EvaluatorEventListener>();
+            listeners.put(eventType, users);
+        }
+        users.add(listener);
+    }
+
+    public void notify(EvaluatorEvent event) {
+        Type eventType = event.getType();
+        List<EvaluatorEventListener> users = listeners.get(eventType);
+        if (users != null) {
+            for (EvaluatorEventListener listener : users) {
+                Map<String, Object> handlerResult = listener.handle(event);
+                if (handlerResult != null) {
+                    listenerData.putAll(handlerResult);
+                }
+            }
+        }
+    }
+}