builtins: update json.is_valid and yaml.is_valid for OPA v0.44.0

Signed-off-by: Stephan Renatus <stephan.renatus@gmail.com>

Author: srenatus

.github/workflows/ci.yml

@@ -31,7 +31,7 @@ jobs:
         node-version: [14.x, 16.x, 18.x]
         opa-version:
         - 0.30.2 # last version with ABI 1.1, 0.31.0+ has ABI 1.2
-        - 0.41.0 # 0.35.0 is the first release with https://github.com/open-policy-agent/opa/pull/4055
+        - 0.45.0 # 0.35.0 is the first release with https://github.com/open-policy-agent/opa/pull/4055
 
     steps:
     - uses: actions/checkout@v3

src/builtins/json.js

@@ -1,6 +1,6 @@
 function isValidJSON(str) {
   if (typeof str !== "string") {
-    return;
+    return false;
   }
   try {
     JSON.parse(str);

src/builtins/yaml.js

@@ -30,9 +30,8 @@ function parse(str) {
 }
 
 module.exports = {
-  // is_valid is expected to return nothing if input is invalid otherwise
-  // true/false for it being valid YAML.
-  "yaml.is_valid": (str) => typeof str === "string" ? parse(str).ok : undefined,
+  // is_valid is expected to return false if input is invalid; and true/false for it being valid YAML.
+  "yaml.is_valid": (str) => typeof str === "string" && parse(str).ok,
   "yaml.marshal": (data) => yaml.stringify(data),
   "yaml.unmarshal": (str) => parse(str).result,
 };