fix: default to precedence 1 for custom operators

src/tokens/operator-token.ts

@@ -25,6 +25,7 @@ export class OperatorToken extends Token {
     this.operator = this.getText()
   }
   getPrecedence () {
-    return precedence[this.getText()]
+    const key = this.getText()
+    return key in precedence ? precedence[key] : 1
   }
 }

test/integration/liquid/operators-option.ts

@@ -24,4 +24,11 @@ describe('LiquidOptions#operators', function () {
     const second = await engine.parseAndRender('{% if "foo" isFooBar "foo" %}True{% else %}False{% endif %}')
     expect(second).to.equal('False')
   })
+
+  it('should evaluate a custom operator with the correct precedence', async function () {
+    const first = await engine.parseAndRender('{% if "foo" isFooBar "bar" or "foo" == "bar" %}True{% else %}False{% endif %}')
+    expect(first).to.equal('True')
+    const second = await engine.parseAndRender('{% if "foo" isFooBar "foo" or "foo" == "bar" %}True{% else %}False{% endif %}')
+    expect(second).to.equal('False')
+  })
 })