From d6bfcc5052dcba18c521a20d62e2e67a81819112 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mateusz=20Burzy=C5=84ski?= <mateuszburzynski@gmail.com>
Date: Wed, 1 Jun 2022 08:38:17 +0200
Subject: [PATCH] Improve the error message when a package referenced in a
 changeset can't be found (#767)

---
 .changeset/ninety-moose-give.md                        | 6 ++++++
 packages/assemble-release-plan/src/flatten-releases.ts | 4 +++-
 2 files changed, 9 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/ninety-moose-give.md

diff --git a/.changeset/ninety-moose-give.md b/.changeset/ninety-moose-give.md
new file mode 100644
index 000000000..0e67e0483
--- /dev/null
+++ b/.changeset/ninety-moose-give.md
@@ -0,0 +1,6 @@
+---
+"@changesets/assemble-release-plan": patch
+"@changesets/cli": patch
+---
+
+Improve the error message when a package referenced in a changeset can't be found. The message will now also include the changeset's ID.
diff --git a/packages/assemble-release-plan/src/flatten-releases.ts b/packages/assemble-release-plan/src/flatten-releases.ts
index e82c6a055..d02dcb069 100644
--- a/packages/assemble-release-plan/src/flatten-releases.ts
+++ b/packages/assemble-release-plan/src/flatten-releases.ts
@@ -21,7 +21,9 @@ export default function flattenReleases(
         let release = releases.get(name);
         let pkg = packagesByName.get(name);
         if (!pkg) {
-          throw new Error(`Could not find package information for ${name}`);
+          throw new Error(
+            `"${changeset.id}" changeset mentions a release for a package "${name}" but such a package could not be found.`
+          );
         }
         if (!release) {
           release = {