electrum-store - npm Package Compare versions

Comparing version 1.12.0 to 2.0.0

lib/store/state.js

@@ -14,2 +14,5 @@ 'use strict';
 
+Object.freeze(emptyValues);
+Object.freeze(secretKey);
+
 function isPositiveInteger(value) {
@@ -64,5 +67,10 @@ if (typeof value === 'number') {
     }
-    if (values.length === 0) {
+    if (isEmpty(values)) {
       values = emptyValues; // optimize for values set to {}
-    }
+    } else {
+        Object.freeze(values);
+        for (let key of Object.getOwnPropertyNames(values)) {
+          State.freezeTop(values[key]);
+        }
+      }
 
@@ -391,2 +399,25 @@ this._id = id;
     }
+  }, {
+    key: 'freeze',
+    value: function freeze(obj) {
+      if (Array.isArray(obj)) {
+        obj.forEach(x => State.freeze(x));
+      }
+      if (obj && typeof obj === 'object') {
+        Object.freeze(obj);
+        for (let key of Object.getOwnPropertyNames(obj)) {
+          State.freeze(obj[key]);
+        }
+      }
+    }
+  }, {
+    key: 'freezeTop',
+    value: function freezeTop(obj) {
+      if (Array.isArray(obj)) {
+        obj.forEach(x => State.freezeTop(x));
+      }
+      if (obj && typeof obj === 'object') {
+        Object.freeze(obj);
+      }
+    }
   }]);
@@ -393,0 +424,0 @@

package.json

 {
   "name": "electrum-store",
-  "version": "1.12.0",
+  "version": "2.0.0",
   "description": "Electrum store provides a store implementation tailored for Electrum.",
@@ -5,0 +5,0 @@ "main": "lib/index.js",

README.md

@@ -119,3 +119,3 @@ # Electrum Store
 expect (state.generation).to.equal (2);
-expect (state.shouldUpdate (1)).to.be.false ();  // provided gen=1 older than state.generation 
+expect (state.shouldUpdate (1)).to.be.false ();  // provided gen=1 older than state.generation
 expect (state.shouldUpdate (2)).to.be.true ();
@@ -140,3 +140,3 @@ expect (state.shouldUpdate (3)).to.be.true ();
 expect (store.select ('a.b').get ('name')).to.equal ('foo');
-expect (store.select ('a.b.c').get ('value')).to.equal ('bar'); 
+expect (store.select ('a.b.c').get ('value')).to.equal ('bar');
 ```
@@ -301,2 +301,31 @@
 
+## Setting values freezes them
+
+When setting values on a state object, we do not want them to be
+mutated arbitrarily by an external source (at least at the top
+level).
+
+In order to prevent mutation of values stored in a state object,
+every value is automatically frozen (`Object.freeze()`):
+
+```javascript
+const state = State.create ('a').set ('x', {foo: 'bar'});
+expect (Object.isFrozen (state.get ('x'))).to.be.true ();
+expect (() => state.get ('x').foo = 'baz').to.throw ();
+```
+
+If the value is an array, the values of the array will also be
+frozen (recursively for sub-arrays).
+
+## Explicit freeze API
+
+The `State` class exposes two methods to explicitly freeze
+objects:
+
+* `State.freeze(obj)` → freezes recursively the full object
+  tree.
+* `State.freezeTop(obj)` → freezes the object; if it is an
+  array, then every item of the array will be frozen by calling
+  `freezeTop()` recursively.
+
 ## Mutate state in a store
@@ -303,0 +332,0 @@

src.test/state-static.js

@@ -33,2 +33,10 @@ 'use strict';
     });
+
+    it ('freezes the initial values', () => {
+      const state = State.create ('a', {o: {foo: 'bar'}});
+      const ref = state.get ('o');
+      expect (ref).to.deep.equal ({foo: 'bar'});
+      expect (() => ref.foo = 'baz').to.throw ();
+      expect (ref).to.deep.equal ({foo: 'bar'});
+    });
   });
@@ -166,2 +174,49 @@
   });
+
+  describe ('State.freeze()', () => {
+    it ('accepts plain values', () => {
+      expect (() => State.freeze (undefined)).to.not.throw ();
+      expect (() => State.freeze (1)).to.not.throw ();
+      expect (() => State.freeze ('hello')).to.not.throw ();
+      expect (() => State.freeze (function (x) {
+        return x;
+      })).to.not.throw ();
+    });
+
+    it ('freezes deeply an object', () => {
+      const obj = {x: 1, y: {a: ['A', [{q: 'Q'}]]}};
+      State.freeze (obj);
+      expect (Object.isFrozen (obj)).to.be.true ();
+      expect (Object.isFrozen (obj.x)).to.be.true ();
+      expect (Object.isFrozen (obj.y)).to.be.true ();
+      expect (Object.isFrozen (obj.y.a)).to.be.true ();
+      expect (Object.isFrozen (obj.y.a[0])).to.be.true ();
+      expect (Object.isFrozen (obj.y.a[1])).to.be.true ();
+      expect (Object.isFrozen (obj.y.a[1][0])).to.be.true ();
+      expect (Object.isFrozen (obj.y.a[1][0].q)).to.be.true ();
+      //  Just to make sure...
+      expect (() => obj.y.a[1][0].r = 'R').to.throw ();
+    });
+  });
+
+  describe ('State.freezeTop()', () => {
+    it ('freezes top level only', () => {
+      const obj = {x: 1, y: {a: 'A'}};
+      State.freezeTop (obj);
+      expect (Object.isFrozen (obj)).to.be.true ();
+      expect (Object.isFrozen (obj.x)).to.be.true ();
+      expect (Object.isFrozen (obj.y)).to.be.false ();
+      expect (() => obj.y.a = 'B').to.not.throw ();
+    });
+
+    it ('freezes top level only, but walks arrays', () => {
+      const obj = [{x: 1, y: {a: 'A'}}];
+      State.freezeTop (obj);
+      expect (Object.isFrozen (obj)).to.be.true ();
+      expect (Object.isFrozen (obj[0])).to.be.true ();
+      expect (Object.isFrozen (obj[0].x)).to.be.true ();
+      expect (Object.isFrozen (obj[0].y)).to.be.false ();
+      expect (() => obj[0].y.a = 'B').to.not.throw ();
+    });
+  });
 });

src.test/state.js

@@ -40,3 +40,3 @@ 'use strict';
   describe ('set()', () => {
-    it ('produces new instance of state', () => {
+    it ('produces new instance of state (with key)', () => {
       const state1 = State.create ('a', {a: 1});
@@ -49,3 +49,3 @@ const state2 = state1.set ('b', 2);
 
-    it ('produces new instance of state', () => {
+    it ('produces new instance of state (without key)', () => {
       const state1 = State.create ('a', {'': 'x'});
@@ -56,2 +56,44 @@ const state2 = state1.set ('y');
     });
+
+    it ('freezes an object value', () => {
+      const state = State.create ('a').set ('x', {a: 1});
+      const ref = state.get ('x');
+      expect (ref).to.deep.equal ({a: 1});
+      expect (() => ref.a = 2).to.throw ();
+      expect (ref).to.deep.equal ({a: 1});
+    });
+
+    it ('freezes an array value', () => {
+      const state = State.create ('a').set ('x', [1, 2]);
+      const ref = state.get ('x');
+      expect (ref).to.deep.equal ([1, 2]);
+      expect (() => ref.a.push (3)).to.throw ();
+      expect (ref).to.deep.equal ([1, 2]);
+    });
+
+    it ('freezes the top level of an object', () => {
+      const state = State.create ('a').set ('x', [{a: 1}, {b: {x: 2}}]);
+      const ref = state.get ('x');
+      expect (Object.isFrozen (ref[0])).to.be.true ();
+      expect (Object.isFrozen (ref[1])).to.be.true ();
+      expect (Object.isFrozen (ref[1].b)).to.be.false ();
+      expect (ref).to.deep.equal ([{a: 1}, {b: {x: 2}}]);
+      expect (() => ref[0].a = 0).to.throw ();
+      expect (() => ref[1].b = 0).to.throw ();
+      expect (() => ref[1].b.x = 0).to.not.throw ();
+      expect (ref).to.deep.equal ([{a: 1}, {b: {x: 0}}]);
+    });
+
+    it ('freezes deeply arrays up to the top level objects', () => {
+      const state = State.create ('a').set ('x', [{a: 1}, [{b: {x: 2}}]]);
+      const ref = state.get ('x');
+      expect (Object.isFrozen (ref[0])).to.be.true ();
+      expect (Object.isFrozen (ref[1])).to.be.true ();
+      expect (Object.isFrozen (ref[1][0])).to.be.true ();
+      expect (Object.isFrozen (ref[1][0].b)).to.be.false ();
+      expect (ref).to.deep.equal ([{a: 1}, [{b: {x: 2}}]]);
+      expect (() => ref[0].a = 0).to.throw ();
+      expect (() => ref[1][0].b.x = 0).to.not.throw ();
+      expect (ref).to.deep.equal ([{a: 1}, [{b: {x: 0}}]]);
+    });
   });
@@ -58,0 +100,0 @@

src/store/state.js

@@ -9,2 +9,5 @@ 'use strict';
 
+Object.freeze (emptyValues);
+Object.freeze (secretKey);
+
 function isPositiveInteger (value) {
@@ -55,4 +58,9 @@ if (typeof value === 'number') {
     }
-    if (values.length === 0) {
+    if (isEmpty (values)) {
       values = emptyValues; // optimize for values set to {}
+    } else {
+      Object.freeze (values);
+      for (let key of Object.getOwnPropertyNames (values)) {
+        State.freezeTop (values[key]);
+      }
     }
@@ -340,2 +348,23 @@
   }
+
+  static freeze (obj) {
+    if (Array.isArray (obj)) {
+      obj.forEach (x => State.freeze (x));
+    }
+    if (obj && typeof obj === 'object') {
+      Object.freeze (obj);
+      for (let key of Object.getOwnPropertyNames (obj)) {
+        State.freeze (obj[key]);
+      }
+    }
+  }
+
+  static freezeTop (obj) {
+    if (Array.isArray (obj)) {
+      obj.forEach (x => State.freezeTop (x));
+    }
+    if (obj && typeof obj === 'object') {
+      Object.freeze (obj);
+    }
+  }
 }
@@ -342,0 +371,0 @@

New alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Fixed alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

95062

increased by7.31%

Lines of code

2179

increased by7.08%

Number of lines in readme file

349

increased by9.06%

No dependency changes