Treat numbers in the root scope as number literals

Author: jasny

src/Lexer.ts

@@ -312,7 +312,7 @@ class StreamLexer {
     }
     if (numberLooking.includes(literalString[0])) {
       // eslint-disable-next-line @typescript-eslint/naming-convention
-      const [_, ok] = this.parseJSON(literalString);
+      const [, ok] = this.parseJSON(literalString);
       return ok;
     }
     return false;

src/Parser.ts

@@ -110,6 +110,13 @@ class TokenParser {
     switch (token.type) {
       case Token.TOK_VARIABLE:
         return { type: 'Variable', name: token.value as string };
+      case Token.TOK_NUMBER: {
+        if (this.lookahead(0) === Token.TOK_RBRACKET || this.lookahead(0) === Token.TOK_COMMA) {
+          throw new Error('Syntax error: numeric literal is not allowed as identifier.');
+        } else {
+          return { type: 'Literal', value: token.value };
+        }
+      }
       case Token.TOK_LITERAL:
         return { type: 'Literal', value: token.value };
       case Token.TOK_UNQUOTEDIDENTIFIER: {
@@ -190,7 +197,7 @@ class TokenParser {
       }
       case Token.TOK_LPAREN: {
         const args: ExpressionNode[] = [];
-        let expression = this.expression(0);
+        const expression = this.expression(0);
         args.push(expression);
         this.match(Token.TOK_RPAREN);
         return args[0];

test/jmespath-extensions.spec.ts

@@ -216,3 +216,47 @@ describe('root', () => {
     expect(value).toEqual([1, 99]);
   });
 });
+
+describe('arithmetic', () => {
+  it('should add', () => {
+    const value = search({ foo: 60, bar: 10 }, 'foo + bar');
+    expect(value).toEqual(70);
+  });
+
+  it('should subtract', () => {
+    const value = search({ foo: 60, bar: 10 }, 'foo - bar');
+    expect(value).toEqual(50);
+  });
+
+  it('should multiply', () => {
+    const value = search({ foo: 60, bar: 10 }, 'foo * bar');
+    expect(value).toEqual(600);
+  });
+
+  it('should divide', () => {
+    const value = search({ foo: 60, bar: 10 }, 'foo / bar');
+    expect(value).toEqual(6);
+  });
+
+  it('should mod', () => {
+    const value = search({ foo: 62, bar: 10 }, 'foo % bar');
+    expect(value).toEqual(2);
+  });
+
+  it('should div', () => {
+    const value = search({ foo: 62, bar: 10 }, 'foo // bar');
+    expect(value).toEqual(6);
+  });
+});
+
+describe('number literals', () => {
+  it('should compare number literals', () => {
+    const value = search({ foo: 60, bar: 10 }, 'foo > 50');
+    expect(value).toEqual(true);
+  });
+
+  it('should add number literals', () => {
+    const value = search({}, '10 + 60');
+    expect(value).toEqual(70);
+  });
+});