From d0eefc499a199f23ea421d21a3110cdd2c3ea595 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20Adel=C3=B6w?= <freben@gmail.com>
Date: Mon, 8 Aug 2022 16:12:21 +0200
Subject: [PATCH] Make Link.to and Button.to more strict
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Signed-off-by: Fredrik Adelöw <freben@gmail.com>
---
 .changeset/tasty-falcons-press.md                     | 5 +++++
 packages/core-components/api-report.md                | 5 +++--
 packages/core-components/src/components/Link/Link.tsx | 5 +++--
 3 files changed, 11 insertions(+), 4 deletions(-)
 create mode 100644 .changeset/tasty-falcons-press.md

diff --git a/.changeset/tasty-falcons-press.md b/.changeset/tasty-falcons-press.md
new file mode 100644
index 0000000000..288f527e17
--- /dev/null
+++ b/.changeset/tasty-falcons-press.md
@@ -0,0 +1,5 @@
+---
+'@backstage/core-components': minor
+---
+
+Made the `to` prop of `Button` and `Link` more strict, only supporting plain strings. It used to be the case that this prop was unexpectedly too liberal, making it look like we supported the complex `react-router-dom` object form of the parameter as well, which led to unexpected results at runtime.
diff --git a/packages/core-components/api-report.md b/packages/core-components/api-report.md
index 4e3820967a..1cdba47257 100644
--- a/packages/core-components/api-report.md
+++ b/packages/core-components/api-report.md
@@ -613,8 +613,9 @@ export const Link: (props: LinkProps) => JSX.Element;
 // Warning: (ae-missing-release-tag) "LinkProps" is exported by the package, but it is missing a release tag (@alpha, @beta, @public, or @internal)
 //
 // @public (undocumented)
-export type LinkProps = LinkProps_2 &
-  LinkProps_3 & {
+export type LinkProps = Omit<LinkProps_2, 'to'> &
+  Omit<LinkProps_3, 'to'> & {
+    to: string;
     component?: ElementType<any>;
     noTrack?: boolean;
   };
diff --git a/packages/core-components/src/components/Link/Link.tsx b/packages/core-components/src/components/Link/Link.tsx
index 22b203d157..92ac92daad 100644
--- a/packages/core-components/src/components/Link/Link.tsx
+++ b/packages/core-components/src/components/Link/Link.tsx
@@ -47,8 +47,9 @@ const useStyles = makeStyles(
 
 export const isExternalUri = (uri: string) => /^([a-z+.-]+):/.test(uri);
 
-export type LinkProps = MaterialLinkProps &
-  RouterLinkProps & {
+export type LinkProps = Omit<MaterialLinkProps, 'to'> &
+  Omit<RouterLinkProps, 'to'> & {
+    to: string;
     component?: ElementType<any>;
     noTrack?: boolean;
   };