fix: resolve falsy values

src/__tests__/resolver.spec.ts

@@ -224,6 +224,19 @@ describe('resolver', () => {
       expect(resolved.result.hello).toBe('world');
     });
 
+    test('should resolve json pointers pointing to falsy values', async () => {
+      const source = {
+        hello: {
+          $ref: '#/word',
+        },
+        word: '',
+      };
+
+      const resolver = new Resolver();
+      const resolved = await resolver.resolve(source);
+      expect(resolved.result.hello).toBe('');
+    });
+
     test('should only resolve valid $refs', async () => {
       const source = {
         hello: {
@@ -526,6 +539,34 @@ describe('resolver', () => {
       expect(resolved.result).toEqual(source);
     });
 
+    test('should resolve jsonPointer pointing to remote falsy values', async () => {
+      const source = {
+        root: {
+          $ref: 'custom://whatever#/entry',
+        },
+      };
+
+      const reader: Types.IResolver = {
+        async resolve(): Promise<any> {
+          return {
+            entry: 0,
+          };
+        },
+      };
+
+      const resolver = new Resolver({
+        resolvers: {
+          custom: reader,
+        },
+      });
+
+      const resolved = await resolver.resolve(source);
+
+      expect(resolved.result).toEqual({
+        root: 0,
+      });
+    });
+
     test('should support not resolving authorities', async () => {
       const data = {
         hello: 'world',

src/runner.ts

@@ -109,7 +109,7 @@ export class ResolveRunner implements Types.IResolveRunner {
       resolved.result = get(resolved.result, targetPath);
     }
 
-    if (!resolved.result) {
+    if (resolved.result === void 0) {
       resolved.errors.push({
         code: 'POINTER_MISSING',
         message: `'${jsonPointer}' does not exist @ '${this.baseUri.toString()}'`,
@@ -157,7 +157,7 @@ export class ResolveRunner implements Types.IResolveRunner {
           resolved.errors = resolved.errors.concat(r.resolved.errors);
         }
 
-        if (!r.resolved.result) continue;
+        if (r.resolved.result === void 0) continue;
 
         this._source = produce(this._source, (draft: any) => {
           if (r.resolved) {
@@ -207,7 +207,7 @@ export class ResolveRunner implements Types.IResolveRunner {
 
                 resolved.refMap[pathToPointer(dependantPath)] = pathToPointer(pointerPath);
 
-                if (val) {
+                if (val !== void 0) {
                   set(draft, dependantPath, val);
                 } else {
                   resolved.errors.push({