added the very basic stack tracking in SchemioScript to improve the e…

…rror message
ishubin · Jan 28, 2025 · 20bf06d · 20bf06d
1 parent ea1b120
commit 20bf06d
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Showing 6 changed files with 53 additions and 18 deletions.
diff --git a/src/ui/templater/ast.js b/src/ui/templater/ast.js
@@ -442,7 +442,7 @@ class ASTParser extends TokenScanner {
             throw new Error(`Expected function body declaration for "${funcNameToken.v}" function, got: "${funcBodyToken.text}"`);
         }
 
-        const functionAST = parseFunctionDeclarationUsing(funcArgsToken, funcBodyToken);
+        const functionAST = parseFunctionDeclarationUsing(funcArgsToken, funcBodyToken, funcNameToken.v);
         return new ASTAssign(new ASTVarRef(funcNameToken.v), functionAST);
     }
 
@@ -545,7 +545,7 @@ class ASTParser extends TokenScanner {
  * @param {ScriptToken} argsToken
  * @param {ScriptToken} bodyToken
  */
-function parseFunctionDeclarationUsing(argsToken, bodyToken) {
+function parseFunctionDeclarationUsing(argsToken, bodyToken, funcName = '< anonymous >') {
     if (!argsToken) {
         throw new Error('Cannot parse function declaration. Missing arguments definition');
     }
@@ -579,7 +579,7 @@ function parseFunctionDeclarationUsing(argsToken, bodyToken) {
 
     const funcBody = parseAST(bodyToken.groupTokens);
 
-    return new ASTFunctionDeclaration(argNames, funcBody);
+    return new ASTFunctionDeclaration(argNames, funcBody, funcName);
 }
 
 /**

diff --git a/src/ui/templater/error.js b/src/ui/templater/error.js
@@ -0,0 +1,19 @@
+export class SchemioScriptError extends Error{
+    constructor(message, scope, error) {
+        super(message);
+        this.message = message;
+        this.scope = scope;
+        this.error = error;
+    }
+
+    print() {
+        let fullMessage = this.message;
+
+        let scope = this.scope;
+        while(scope) {
+            fullMessage += '\n\tat ' + scope.stackName;
+            scope = scope.parent;
+        }
+        console.error(fullMessage);
+    }
+}
diff --git a/src/ui/templater/nodes.js b/src/ui/templater/nodes.js
@@ -11,6 +11,7 @@ import { parseColor } from "../colors";
 import { Color } from "./color";
 import { Area } from "./area";
 import { Fill } from "./fill";
+import { SchemioScriptError } from "./error";
 
 const FUNC_INVOKE = 'funcInvoke';
 const VAR_REF = 'var-ref';
@@ -205,8 +206,8 @@ export class ASTWhileStatement extends ASTNode {
      */
     evalNode(scope) {
         let lastResult = null;
-        while (this.whileExpression.evalNode(scope.newScope())) {
-            lastResult = this.whileBlock.evalNode(scope.newScope());
+        while (this.whileExpression.evalNode(scope.newScope('while expression'))) {
+            lastResult = this.whileBlock.evalNode(scope.newScope('while block'));
         }
         return lastResult;
     }
@@ -235,7 +236,7 @@ export class ASTForLoop extends ASTNode {
      * @param {Scope} scope
      */
     evalNode(scope) {
-        scope = scope.newScope();
+        scope = scope.newScope('for loop');
         this.init.evalNode(scope);
 
         while(this.condition.evalNode(scope)) {
@@ -258,14 +259,14 @@ export class ASTIFStatement extends ASTNode {
     }
 
     evalNode(scope) {
-        const result = this.conditionExpression.evalNode(scope.newScope());
+        const result = this.conditionExpression.evalNode(scope.newScope('if statement'));
         if (result) {
             if (!this.trueBlock) {
                 return null;
             }
-            return this.trueBlock.evalNode(scope.newScope());
+            return this.trueBlock.evalNode(scope.newScope('if block'));
         } else if (this.falseBlock) {
-            return this.falseBlock.evalNode(scope.newScope());
+            return this.falseBlock.evalNode(scope.newScope('else block'));
         }
         return null;
     }
@@ -680,10 +681,11 @@ export class ASTFunctionDeclaration extends ASTNode {
      * @param {Array<String>} argNames
      * @param {ASTNode} body
      */
-    constructor(argNames, body) {
+    constructor(argNames, body, funcName) {
         super('function');
         this.argNames = argNames;
         this.body = body;
+        this.funcName = funcName;
     }
     print() {
         return `(${this.argNames.join(',')}) => {(${this.body.print()})}`;
@@ -694,11 +696,19 @@ export class ASTFunctionDeclaration extends ASTNode {
      */
     evalNode(scope) {
         return (...args) => {
-            const funcScope = scope.newScope();
+            const funcScope = scope.newScope('func ' + this.funcName);
             for (let i = 0; i < args.length && i < this.argNames.length; i++) {
                 funcScope.setLocal(this.argNames[i], args[i]);
             }
-            return this.body.evalNode(funcScope);
+            try {
+                return this.body.evalNode(funcScope);
+            } catch (err) {
+                if (err instanceof SchemioScriptError) {
+                    throw err;
+                } else {
+                    throw new SchemioScriptError(err.message, funcScope, err);
+                }
+            }
         };
     }
 }

diff --git a/src/ui/templater/scope.js b/src/ui/templater/scope.js
@@ -5,8 +5,9 @@ export class Scope {
      * @param {Scope|null} parent
      * @param {function(string): any} externalObjectProvider
      */
-    constructor(data, parent, externalObjectProvider) {
+    constructor(data, parent, externalObjectProvider, stackName = '< unknown >') {
         this.data = data || {};
+        this.stackName = stackName;
         this.parent = parent;
         this.externalObjectProvider = externalObjectProvider;
     }
@@ -54,8 +55,8 @@ export class Scope {
         this.data[varName] = value;
     }
 
-    newScope(data = {}) {
-        return new Scope(data, this, this.externalObjectProvider);
+    newScope(stackName = '< unknown >', data = {}) {
+        return new Scope(data, this, this.externalObjectProvider, stackName);
     }
 
     getData() {

diff --git a/src/ui/templater/struct.js b/src/ui/templater/struct.js
@@ -34,7 +34,7 @@ export class ASTStructNode extends ASTNode {
     evalNode(scope) {
         const initFunc = (...args) => {
             const structObj = {};
-            const structScope = scope.newScope({'this': structObj});
+            const structScope = scope.newScope('struct ' + this.name, {'this': structObj});
 
             this.fieldDefinitions.forEach((fieldDef, idx) => {
                 if (idx < args.length) {

diff --git a/src/ui/templater/templater.js b/src/ui/templater/templater.js
@@ -1,4 +1,5 @@
 import { ASTNode, parseExpression } from "./ast";
+import { SchemioScriptError } from "./error";
 import { List } from "./list";
 import { Scope } from './scope';
 import { parseStringExpression } from "./strings";
@@ -192,7 +193,11 @@ function compileExpression(expr) {
             return ast.evalNode(scope);
         } catch(ex) {
             console.error('Failed to evaluate expression:\n' + expr);
-            console.error(ex);
+            if (ex instanceof SchemioScriptError) {
+                ex.print();
+            } else {
+                console.error(ex);
+            }
         }
     };
 }
@@ -356,7 +361,7 @@ function compileRecursiveBuilder(item, $recurse, customDefinitions) {
         }
         const data = {};
         data[iteratorName] = sourceObject;
-        const iteratorScope = scope.newScope(data);
+        const iteratorScope = scope.newScope('buildObject', data);
 
         const processedObj = itemProcessor(iteratorScope);
         const children = childrenFetcher.evalNode(iteratorScope);