fix(context): disable deep clone of injection metadata

BREAKING CHANGE: the `metadata` parameter of `@inject` is no longer cloned deeply. It's still cloned shallowly.
loopbackio · Mar 26, 2018 · 7d8a84c · 7d8a84c
1 parent 544052e
commit 7d8a84c
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Showing 2 changed files with 45 additions and 18 deletions.
diff --git a/packages/context/src/inject.ts b/packages/context/src/inject.ts
@@ -106,14 +106,20 @@ export function inject(
       // Please note propertyKey is `undefined` for constructor
       const paramDecorator: ParameterDecorator = ParameterDecoratorFactory.createDecorator<
         Injection
-      >(PARAMETERS_KEY, {
-        target,
-        member,
-        methodDescriptorOrParameterIndex,
-        bindingKey,
-        metadata,
-        resolve,
-      });
+      >(
+        PARAMETERS_KEY,
+        {
+          target,
+          member,
+          methodDescriptorOrParameterIndex,
+          bindingKey,
+          metadata,
+          resolve,
+        },
+        // Do not deep clone the spec as only metadata is mutable and it's
+        // shallowly cloned
+        {cloneInputSpec: false},
+      );
       paramDecorator(target, member!, methodDescriptorOrParameterIndex);
     } else if (member) {
       // Property or method
@@ -136,14 +142,20 @@ export function inject(
       }
       const propDecorator: PropertyDecorator = PropertyDecoratorFactory.createDecorator<
         Injection
-      >(PROPERTIES_KEY, {
-        target,
-        member,
-        methodDescriptorOrParameterIndex,
-        bindingKey,
-        metadata,
-        resolve,
-      });
+      >(
+        PROPERTIES_KEY,
+        {
+          target,
+          member,
+          methodDescriptorOrParameterIndex,
+          bindingKey,
+          metadata,
+          resolve,
+        },
+        // Do not deep clone the spec as only metadata is mutable and it's
+        // shallowly cloned
+        {cloneInputSpec: false},
+      );
       propDecorator(target, member!);
     } else {
       // It won't happen here as `@inject` is not compatible with ClassDecorator

diff --git a/packages/context/test/unit/inject.test.ts b/packages/context/test/unit/inject.test.ts
@@ -145,8 +145,12 @@ describe('property injection', () => {
     class SubTestClass extends TestClass {
       @inject('bar') foo: string;
     }
-    const meta = describeInjectedProperties(SubTestClass.prototype);
-    expect(meta.foo.bindingKey).to.eql('bar');
+
+    const base = describeInjectedProperties(TestClass.prototype);
+    expect(base.foo.bindingKey).to.eql('foo');
+
+    const sub = describeInjectedProperties(SubTestClass.prototype);
+    expect(sub.foo.bindingKey).to.eql('bar');
   });
 
   it('supports inherited and own properties', () => {
@@ -161,4 +165,15 @@ describe('property injection', () => {
     expect(meta.foo.bindingKey).to.eql('foo');
     expect(meta.bar.bindingKey).to.eql('bar');
   });
+
+  it('does not clone metadata deeply', () => {
+    const options = {x: 1};
+    class TestClass {
+      @inject('foo', options)
+      foo: string;
+    }
+    const meta = describeInjectedProperties(TestClass.prototype);
+    expect(meta.foo.metadata).to.be.not.exactly(options);
+    expect(meta.foo.metadata).to.eql({x: 1, decorator: '@inject'});
+  });
 });