fix(config): throw error if value contain not valid json string

lib/config/util.js

@@ -49,15 +49,11 @@ function parseBoolean(value) {
 }
 
 function parsePrimitive(str) {
-    let value;
-
     try {
-        value = JSON.parse(str);
+        return JSON.parse(str);
     } catch (error) {
-        // do nothing
+        throw new GeminiError('a value must be a primitive type');
     }
-
-    return value;
 }
 
 function positiveIntegerOption(defaultValue) {

test/unit/config-options/config-options.test.js

@@ -236,11 +236,11 @@ describe('config', function() {
             });
         });
 
-        it('should not throws if value from environment is not valid', () => {
+        it('should throw if value from environment is not valid', () => {
             ['{a:1}', '{', ']', '\'string\'', '\n'].forEach((value) => {
-                assert.doesNotThrow(() => {
+                assert.throw(() => {
                     assertParsesEnv({property: name, value});
-                });
+                }, GeminiError);
             });
         });
 
@@ -251,11 +251,11 @@ describe('config', function() {
             });
         });
 
-        it('should not throws if value from cli is not valid', () => {
+        it('should throw if value from cli is not valid', () => {
             ['{a:1}', '{', ']', '\'string\'', '\n'].forEach((value) => {
-                assert.doesNotThrow(() => {
+                assert.throw(() => {
                     assertParsesCli({property: name, value});
-                });
+                }, GeminiError);
             });
         });
     }
@@ -475,7 +475,7 @@ describe('config', function() {
             });
         });
 
-        describe.only('plugins', () => {
+        describe('plugins', () => {
             testObjectOption('system.plugins.plugin');
         });
     });