fix(yaml): modified strain doesn't preserve version-lock on save

fixes #394

src/Strain.js

@@ -268,7 +268,7 @@ class Strain {
       this._ownProperties.forEach((key) => {
         const idx = node.items.findIndex((i) => i.key === key
           || (i.key.value && i.key.value === key));
-        let value = this[key];
+        let value = key === 'version-lock' ? this.versionLock : this[key];
         if (value && value.toYAMLNode) {
           value = value.toYAMLNode();
         }

test/config.test.js

@@ -313,6 +313,18 @@ describe('Helix Config Serializing', () => {
     assert.equal(actual, expected);
   });
 
+  it('can serialize back a modified strain with version-lock and modified package', async () => {
+    const source = await fs.readFile(path.resolve(SPEC_ROOT, 'minimal-lock.yaml'), 'utf-8');
+    const cfg = await new HelixConfig()
+      .withSource(source)
+      .init();
+
+    cfg.strains.get('default').package = 'bfbde5fbfbde5fbfbde5f';
+    const actual = cfg.toYAML();
+    const expected = await fs.readFile(path.resolve(SPEC_ROOT, 'minimal-lock-package.yaml'), 'utf-8');
+    assert.equal(actual, expected);
+  });
+
   it('can serialize back a modified strain with modified package (with refs)', async () => {
     const source = await fs.readFile(path.resolve(SPEC_ROOT, 'minimal-with-refs.yaml'), 'utf-8');
     const cfg = await new HelixConfig()

test/specs/configs/minimal-lock-package.yaml

@@ -0,0 +1,31 @@
+# Copyright 2018 Adobe. All rights reserved.
+# This file is licensed to you under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License. You may obtain a copy
+# of the License at http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software distributed under
+# the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+# OF ANY KIND, either express or implied. See the License for the specific language
+# governing permissions and limitations under the License.
+version: 1
+
+definitions:
+  constants:
+    defaultRepo:
+      &myrepo
+      owner: adobe
+      repo: project-helix.io
+      ref: master
+  strains:
+    base:
+      &basestrain
+      code: *myrepo
+      content: *myrepo
+      static: *myrepo
+
+strains:
+  - name: default
+    <<: *basestrain
+    version-lock:
+      word2md: 1.2.3
+    package: bfbde5fbfbde5fbfbde5f

test/specs/configs/minimal-lock.yaml

@@ -0,0 +1,30 @@
+# Copyright 2018 Adobe. All rights reserved.
+# This file is licensed to you under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License. You may obtain a copy
+# of the License at http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software distributed under
+# the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+# OF ANY KIND, either express or implied. See the License for the specific language
+# governing permissions and limitations under the License.
+version: 1
+
+definitions:
+  constants:
+    defaultRepo:
+      &myrepo
+      owner: adobe
+      repo: project-helix.io
+      ref: master
+  strains:
+    base:
+      &basestrain
+      code: *myrepo
+      content: *myrepo
+      static: *myrepo
+
+strains:
+  - name: default
+    <<: *basestrain
+    version-lock:
+      word2md: 1.2.3