Merge branch 'main' of github.com:rudderlabs/rudder-json-template-engine

.vscode/launch.json

@@ -33,13 +33,24 @@
       }
     },
     {
-      "name": "Test Scenario",
-      "program": "${workspaceFolder}/test/test_scenario.ts",
+      "runtimeExecutable": "/usr/local/bin/node",
+      "name": "Jest Scenario",
+      "program": "${workspaceFolder}/node_modules/.bin/jest",
       "request": "launch",
-      "runtimeArgs": ["--nolazy", "-r", "ts-node/register/transpile-only"],
       "skipFiles": ["<node_internals>/**"],
-      "args": ["--scenario=${input:scenario}", "--index=${input:index}"],
-      "type": "node"
+      "args": [
+        "scenario.test",
+        "--config",
+        "jest.config.ts",
+        "--scenario=${input:scenario}",
+        "--index=${input:index}"
+      ],
+      "type": "node",
+      "console": "integratedTerminal",
+      "internalConsoleOptions": "neverOpen",
+      "windows": {
+        "program": "${workspaceFolder}/node_modules/jest/bin/jest"
+      }
     },
     {
       "runtimeExecutable": "/usr/local/bin/node",

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## [0.8.1](https://github.com/rudderlabs/rudder-json-template-engine/compare/v0.8.0...v0.8.1) (2023-10-18)
+
+
+### Bug Fixes
+
+* **INT-833:** conditional expression parsing is failing parse objects ([#46](https://github.com/rudderlabs/rudder-json-template-engine/issues/46)) ([bf27bae](https://github.com/rudderlabs/rudder-json-template-engine/commit/bf27baec9011d54d449adf8c1b4f5ce72d7f3444))
+
 ## [0.8.0](https://github.com/rudderlabs/rudder-json-template-engine/compare/v0.7.0...v0.8.0) (2023-10-10)
 
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@rudderstack/json-template-engine",
-  "version": "0.8.0",
+  "version": "0.8.1",
   "homepage": "https://github.com/rudderlabs/rudder-json-template-engine",
   "description": "A library for evaluating JSON template expressions.",
   "main": "build/index.js",

src/lexer.ts

@@ -13,7 +13,6 @@ export class JsonTemplateLexer {
   private readonly codeChars: string[];
   private buf: Token[];
   private idx = 0;
-  private lastParsedToken?: Token;
 
   constructor(template: string) {
     this.buf = [];
@@ -29,6 +28,11 @@ export class JsonTemplateLexer {
     return this.idx;
   }
 
+  reset(idx: number) {
+    this.idx = idx;
+    this.buf = [];
+  }
+
   getCode(start: number, end: number): string {
     return this.codeChars.slice(start, end).join('');
   }
@@ -272,12 +276,11 @@ export class JsonTemplateLexer {
   lex(): Token {
     if (this.buf[0]) {
       this.idx = this.buf[0].range[1];
-      this.lastParsedToken = this.buf[0];
+      let token = this.buf[0];
       this.buf = this.buf.slice(1);
-      return this.lastParsedToken;
+      return token;
     }
-    this.lastParsedToken = this.advance();
-    return this.lastParsedToken;
+    return this.advance();
   }
 
   static isLiteralToken(token: Token) {

src/parser.ts

@@ -35,7 +35,7 @@ import {
   LoopExpression,
   IncrementExpression,
 } from './types';
-import { JsonTemplateParserError } from './errors';
+import { JsonTemplateLexerError, JsonTemplateParserError } from './errors';
 import { BINDINGS_PARAM_KEY, DATA_PARAM_KEY } from './constants';
 import { JsonTemplateLexer } from './lexer';
 import { CommonUtils } from './utils';
@@ -471,8 +471,16 @@ export class JsonTemplateParser {
   }
 
   private parseConditionalBodyExpr(): Expression {
+    const currentIndex = this.lexer.currentIndex();
     if (this.lexer.match('{')) {
-      return this.parseCurlyBlockExpr({ blockEnd: '}', parentType: SyntaxType.CONDITIONAL_EXPR });
+      try {
+        return this.parseObjectExpr();
+      } catch (error: any) {
+        if (error instanceof JsonTemplateLexerError) {
+          this.lexer.reset(currentIndex);
+        }
+        return this.parseCurlyBlockExpr({ blockEnd: '}', parentType: SyntaxType.CONDITIONAL_EXPR });
+      }
     }
     return this.parseBaseExpr();
   }

test/scenarios/conditions/data.ts

@@ -1,14 +1,6 @@
 import { Scenario } from '../../types';
 
 export const data: Scenario[] = [
-  {
-    templatePath: 'empty_if.jt',
-    error: 'Empty statements are not allowed in loop and condtional expressions',
-  },
-  {
-    templatePath: 'empty_then.jt',
-    error: 'Empty statements are not allowed in loop and condtional expressions',
-  },
   {
     templatePath: 'if_block.jt',
     input: {
@@ -58,6 +50,20 @@ export const data: Scenario[] = [
     },
     output: 5,
   },
+  {
+    templatePath: 'objects.jt',
+    input: {
+      a: 5,
+    },
+    output: { message: 'a > 1' },
+  },
+  {
+    templatePath: 'objects.jt',
+    input: {
+      a: 0,
+    },
+    output: { message: 'a <= 1' },
+  },
   {
     input: {
       a: 5,

test/scenarios/conditions/objects.jt

@@ -0,0 +1 @@
+.a > 1 ? { message: "a > 1" } : { message: "a <= 1" }

test_engine_local1.ts

@@ -0,0 +1,6 @@
+import { JsonTemplateEngine } from './src';
+
+console.log(
+  JsonTemplateEngine.translate(`
+.output ? .output : { "foo": "bar" }`),
+);