Test json parse errors (#8103)

src/language-js/parser-babel.js

@@ -140,11 +140,10 @@ function assertJsonNode(node, parent) {
     case "ObjectExpression":
       return node.properties.forEach(assertJsonChildNode);
     case "ObjectProperty":
-      // istanbul ignore if
       if (node.computed) {
         throw createJsonError("computed");
       }
-      // istanbul ignore if
+
       if (node.shorthand) {
         throw createJsonError("shorthand");
       }
@@ -154,7 +153,6 @@ function assertJsonNode(node, parent) {
         case "+":
         case "-":
           return assertJsonChildNode(node.argument);
-        // istanbul ignore next
         default:
           throw createJsonError("operator");
       }
@@ -168,7 +166,6 @@ function assertJsonNode(node, parent) {
     case "NumericLiteral":
     case "StringLiteral":
       return;
-    // istanbul ignore next
     default:
       throw createJsonError();
   }
@@ -177,7 +174,6 @@ function assertJsonNode(node, parent) {
     return assertJsonNode(child, node);
   }
 
-  // istanbul ignore next
   function createJsonError(attribute) {
     const name = !attribute
       ? node.type

tests/errors/json/__snapshots__/jsfmt.spec.js.snap

@@ -0,0 +1,37 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`snippet: #0 error test 1`] = `
+"ObjectProperty with shorthand=true is not allowed in JSON. (1:2)
+> 1 | {foo}
+    |  ^"
+`;
+
+exports[`snippet: #1 error test 1`] = `
+"ObjectProperty with computed=true is not allowed in JSON. (1:2)
+> 1 | {[\\"foo\\"]:\\"bar\\"}
+    |  ^"
+`;
+
+exports[`snippet: #2 error test 1`] = `
+"UnaryExpression with operator=\\"~\\" is not allowed in JSON. (1:9)
+> 1 | {\\"foo\\": ~1}
+    |         ^"
+`;
+
+exports[`snippet: #3 error test 1`] = `
+"LogicalExpression is not allowed in JSON. (1:9)
+> 1 | {\\"foo\\": false || \\"bar\\"}
+    |         ^"
+`;
+
+exports[`snippet: #4 error test 1`] = `
+"Identifier is not allowed in JSON. (1:9)
+> 1 | {\\"foo\\": undefined}
+    |         ^"
+`;
+
+exports[`snippet: #5 error test 1`] = `
+"ArrowFunctionExpression is not allowed in JSON. (1:9)
+> 1 | {\\"foo\\": () => {}}
+    |         ^"
+`;

tests/errors/json/jsfmt.spec.js

@@ -0,0 +1,14 @@
+run_spec(
+  {
+    dirname: __dirname,
+    snippets: [
+      "{foo}",
+      '{["foo"]:"bar"}',
+      '{"foo": ~1}',
+      '{"foo": false || "bar"}',
+      '{"foo": undefined}',
+      '{"foo": () => {}}',
+    ],
+  },
+  ["json-stringify"]
+);