breaking: don't serialize true/false/NaN keys, have IDB reject them

Author: vweevers

README.md

@@ -122,7 +122,6 @@ Note that this behavior is slightly different from values due to the way that In
 If the environment does not support a type, it will throw an error which `level-js` catches and passes to the callbacks of `get`, `put`, `del`, `batch` or an iterator. Exceptions are:
 
 - `null` and `undefined`: rejected early by `abstract-leveldown`
-- Boolean and `NaN`: though invalid per the IndexedDB specification, they are converted to strings for `abstract-leveldown` compatibility;
 - Binary and array keys: if not supported by the environment, `level-js` falls back to `String(key)`.
 
 ### Normalization

index.js

@@ -145,10 +145,6 @@ Level.prototype._serializeKey = function (key) {
     return Level.binaryKeys ? key : key.toString()
   } else if (Array.isArray(key)) {
     return Level.arrayKeys ? key.map(this._serializeKey, this) : String(key)
-  } else if (typeof key === 'boolean' || (typeof key === 'number' && isNaN(key))) {
-    // These types are invalid per the IndexedDB spec and ideally we'd treat
-    // them that way, but they're valid per the current abstract test suite.
-    return String(key)
   } else {
     return key
   }

test/index.js

@@ -34,4 +34,3 @@ require('./custom-test')(leveljs, test, testCommon)
 require('./structured-clone-test')(leveljs, test, testCommon)
 require('./key-type-test')(leveljs, test, testCommon)
 require('./key-type-illegal-test')(leveljs, test, testCommon)
-require('./key-type-stringified-test')(leveljs, test, testCommon)

test/key-type-illegal-test.js

@@ -13,6 +13,9 @@ var illegalTypes = [
   { name: 'DOMNode', key: global.document, error: 'DataError' },
   { name: 'Boolean(true)', key: new Boolean(true), error: 'DataError' }, // eslint-disable-line
   { name: 'Boolean(false)', key: new Boolean(false), error: 'DataError' }, // eslint-disable-line
+  { name: 'true', key: true, error: 'DataError' },
+  { name: 'false', key: false, error: 'DataError' },
+  { name: 'NaN', key: NaN, error: 'DataError' }
 ]
 
 // These are only tested if the environment supports array keys.