Merge pull request #2 from jg-rp/operator-precedence

Fix JSONPath filter operator precedence.

CHANGELOG.md

@@ -1,5 +1,11 @@
 # JSON P3 Change Log
 
+# Version 0.2.1
+
+**Fixes**
+
+- Fixed JSONPath filter operator precedence. Previously logical _and_ (`&&`) and _or_ (`||`) were binding more tightly than logical negation (`!`).
+
 # Version 0.2.0
 
 **Breaking Changes**

package.json

@@ -1,6 +1,6 @@
 {
   "name": "json-p3",
-  "version": "0.2.0",
+  "version": "0.2.1",
   "author": "James Prior",
   "license": "MIT",
   "description": "JSONPath, JSON Pointer and JSON Patch",

src/path/parse.ts

@@ -29,10 +29,10 @@ import {
 import { Token, TokenKind, TokenStream } from "./token";
 
 const PRECEDENCE_LOWEST = 1;
-const PRECEDENCE_LOGICALRIGHT = 3;
 const PRECEDENCE_LOGICAL_AND = 4;
 const PRECEDENCE_LOGICAL_OR = 5;
 const PRECEDENCE_COMPARISON = 6;
+const PRECEDENCE_PREFIX = 7;
 
 const PRECEDENCES: Map<TokenKind, number> = new Map([
   [TokenKind.AND, PRECEDENCE_LOGICAL_AND],
@@ -42,7 +42,7 @@ const PRECEDENCES: Map<TokenKind, number> = new Map([
   [TokenKind.LE, PRECEDENCE_COMPARISON],
   [TokenKind.LT, PRECEDENCE_COMPARISON],
   [TokenKind.NE, PRECEDENCE_COMPARISON],
-  [TokenKind.NOT, PRECEDENCE_LOGICALRIGHT],
+  [TokenKind.NOT, PRECEDENCE_PREFIX],
   [TokenKind.OR, PRECEDENCE_LOGICAL_OR],
   [TokenKind.RPAREN, PRECEDENCE_LOWEST],
 ]);
@@ -312,7 +312,7 @@ export class Parser {
     return new PrefixExpression(
       stream.current,
       "!",
-      this.parseFilterExpression(stream, PRECEDENCE_LOGICALRIGHT),
+      this.parseFilterExpression(stream, PRECEDENCE_PREFIX),
     );
   }
 

tests/path/parse.test.ts

@@ -1,6 +1,44 @@
-import { JSONPathSyntaxError, compile, query } from "../../src/path";
+import {
+  JSONPathEnvironment,
+  JSONPathSyntaxError,
+  compile,
+  query,
+} from "../../src/path";
+
+type TestCase = {
+  description: string;
+  path: string;
+  want: string;
+};
+
+const TEST_CASES: TestCase[] = [
+  {
+    description: "not binds more tightly than and",
+    path: "$[[email protected] && [email protected]]",
+    want: "$[?(!@['a'] && !@['b'])]",
+  },
+  {
+    description: "not binds more tightly than or",
+    path: "$[[email protected] || [email protected]]",
+    want: "$[?(!@['a'] || !@['b'])]",
+  },
+  {
+    description: "control precedence with parens",
+    path: "$[?!(@.a && [email protected])]",
+    want: "$[?!(@['a'] && !@['b'])]",
+  },
+];
 
 describe("parse", () => {
+  const env = new JSONPathEnvironment();
+
+  test.each<TestCase>(TEST_CASES)(
+    "$description",
+    ({ path, want }: TestCase) => {
+      expect(env.compile(path).toString()).toBe(want);
+    },
+  );
+
   test("well-typed nested functions", () => {
     const data = {
       regex: "a.*",