Fix a bug with linked packages where it would break if there was a li…

…nked package that didn't have a changeset (#33)

* Fix a bug with linked packages where it would break if there was a linked package that didn't have a changeset

* Add a changeset

.changeset/9c2cafae/changes.json

@@ -0,0 +1,4 @@
+{
+  "releases": [{ "name": "@changesets/cli", "type": "patch" }],
+  "dependents": []
+}

.changeset/9c2cafae/changes.md

@@ -0,0 +1 @@
+Fix a bug with linked packages where it would break if there was a linked package that didn't have a changeset

packages/cli/src/commands/bump/__tests__/consume.js

@@ -134,6 +134,21 @@ describe("running version in a simple project", () => {
     );
   });
 
+  it("should not break when there is a linked package without a changeset", async () => {
+    const cwd2 = await copyFixtureIntoTempDir(__dirname, "linked-packages");
+    const spy = jest.spyOn(fs, "writeFile");
+    await writeChangesets([simpleChangeset], cwd2);
+
+    await versionCommand({ cwd: cwd2 });
+    const calls = spy.mock.calls;
+
+    expect(JSON.parse(calls[0][1])).toEqual(
+      expect.objectContaining({ name: "pkg-a", version: "1.1.0" })
+    );
+
+    expect(spy).toHaveBeenCalledTimes(2);
+  });
+
   describe("when there are multiple changeset commits", () => {
     it("should bump releasedPackages", async () => {
       await writeChangesets([simpleChangeset, simpleChangeset2], cwd);

packages/cli/src/utils/createRelease/flattenChangesets.js

@@ -46,12 +46,16 @@ export default function flattenReleases(changesets, allLinkedPackages) {
     const allBumpTypes = [];
     for (let linkedPackage of linkedPackages) {
       let release = flatReleases.get(linkedPackage);
-      allBumpTypes.push(release.type);
+      if (release) {
+        allBumpTypes.push(release.type);
+      }
     }
     const highestBumpType = maxType(allBumpTypes);
     for (let linkedPackage of linkedPackages) {
       let release = flatReleases.get(linkedPackage);
-      release.type = highestBumpType;
+      if (release) {
+        release.type = highestBumpType;
+      }
     }
   }