fix(core): fix casting symbol values to strings in the prop type check warning

src/core/util/props.js

@@ -210,7 +210,8 @@ function getInvalidTypeMessage (name, value, expectedTypes) {
   // check if we need to specify expected value
   if (expectedTypes.length === 1 &&
       isExplicable(expectedType) &&
-      !isBoolean(expectedType, receivedType)) {
+      !isBoolean(expectedType, receivedType) &&
+      !isSymbol(expectedType, receivedType)) {
     message += ` with value ${expectedValue}`
   }
   message += `, got ${receivedType} `
@@ -223,11 +224,11 @@ function getInvalidTypeMessage (name, value, expectedTypes) {
 
 function styleValue (value, type) {
   if (type === 'String') {
-    return `"${value}"`
+    return `"${String(value)}"`
   } else if (type === 'Number') {
-    return `${Number(value)}`
+    return `${Number(String(value))}`
   } else {
-    return `${value}`
+    return String(value)
   }
 }
 
@@ -239,3 +240,7 @@ function isExplicable (value) {
 function isBoolean (...args) {
   return args.some(elem => elem.toLowerCase() === 'boolean')
 }
+
+function isSymbol (...args) {
+  return args.some(elem => elem.toLowerCase() === 'symbol')
+}

test/unit/features/options/props.spec.js

@@ -241,6 +241,36 @@ describe('Options props', () => {
         makeInstance({}, Symbol)
         expect('Expected Symbol, got Object').toHaveBeenWarned()
       })
+
+      it('string & symbol', () => {
+        makeInstance(Symbol('foo'), String)
+        expect('Expected String, got Symbol').toHaveBeenWarned()
+      })
+
+      it('number & symbol', () => {
+        makeInstance(Symbol('foo'), Number)
+        expect('Expected Number, got Symbol').toHaveBeenWarned()
+      })
+
+      it('boolean & symbol', () => {
+        makeInstance(Symbol('foo'), Boolean)
+        expect('Expected Boolean, got Symbol').toHaveBeenWarned()
+      })
+
+      it('function & symbol', () => {
+        makeInstance(Symbol('foo'), Function)
+        expect('Expected Function, got Symbol').toHaveBeenWarned()
+      })
+
+      it('object & symbol', () => {
+        makeInstance(Symbol('foo'), Object)
+        expect('Expected Object, got Symbol').toHaveBeenWarned()
+      })
+
+      it('array & symbol', () => {
+        makeInstance(Symbol('foo'), Array)
+        expect('Expected Array, got Symbol').toHaveBeenWarned()
+      })
     }
 
     it('custom constructor', () => {