fix(INT-833): conditional expression parsing is failing parse objects (…

…#46) * feat: add support for short key value in object expr * fix: conditional expression parsing is failing parse objects With this fix, conditional expression now accepts both objects and block of statements.
rudderlabs · Oct 18, 2023 · bf27bae · bf27bae
1 parent 501ddbc
commit bf27bae
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Showing 8 changed files with 55 additions and 22 deletions.
diff --git a/.vscode/launch.json b/.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",

diff --git a/src/lexer.ts b/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) {

diff --git a/src/parser.ts b/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();
   }

diff --git a/test/scenarios/conditions/data.ts b/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,

diff --git a/test/scenarios/conditions/empty_if.jt b/test/scenarios/conditions/empty_if.jt
diff --git a/test/scenarios/conditions/empty_then.jt b/test/scenarios/conditions/empty_then.jt
diff --git a/test/scenarios/conditions/objects.jt b/test/scenarios/conditions/objects.jt
@@ -0,0 +1 @@
+.a > 1 ? { message: "a > 1" } : { message: "a <= 1" }
diff --git a/test_engine_local1.ts b/test_engine_local1.ts
@@ -0,0 +1,6 @@
+import { JsonTemplateEngine } from './src';
+
+console.log(
+  JsonTemplateEngine.translate(`
+.output ? .output : { "foo": "bar" }`),
+);
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		.a > 1 ? { message: "a > 1" } : { message: "a <= 1" }