fix(Link): Do not ignore onMouseEnter prop with absolute href

[ericmatthys]

Fixes #22733

Regardless of whether it's recommended that Link be used with external href values or not, they can be used and onMouseEnter being swallowed with an external href value is unexpected behavior.

Bug

• Related issues linked using fixes #number
• Integration tests added
• Errors have helpful link attached, see contributing.md

Documentation / Examples

• Make sure the linting passes by running yarn lint

[ijjk]

Hi, can you add a test for this? It can go in this test suite

[ericmatthys]

@ijjk I added a test. I wasn't sure where exactly it fit best since there weren't others like it, but let me know if it should be moved.

[ijjk]

Stats from current PR

Default Build (Increase detected ⚠️)

General Overall increase ⚠️

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
buildDuration	26.3s	26.5s	⚠️ +171ms
buildDurationCached	4.7s	4.6s	-116ms
nodeModulesSize	347 MB	347 MB	⚠️ +25 B

Page Load Tests Overall increase ✓

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
/ failed reqs	0	0	✓
/ total time (seconds)	4.267	4.342	⚠️ +0.07
/ avg req/sec	585.88	575.83	⚠️ -10.05
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	2.325	2.204	-0.12
/error-in-render avg req/sec	1075.37	1134.35	+58.98

Client Bundles (main, webpack, commons)

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
450.HASH.js gzip	179 B	179 B	✓
framework-HASH.js gzip	42.2 kB	42.2 kB	✓
main-HASH.js gzip	28.4 kB	28.4 kB	✓
webpack-HASH.js gzip	1.45 kB	1.45 kB	✓
Overall change	72.3 kB	72.3 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages Overall decrease ✓

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
_app-HASH.js gzip	1.37 kB	1.37 kB	✓
_error-HASH.js gzip	194 B	194 B	✓
amp-HASH.js gzip	312 B	312 B	✓
css-HASH.js gzip	326 B	326 B	✓
dynamic-HASH.js gzip	2.38 kB	2.38 kB	✓
head-HASH.js gzip	350 B	350 B	✓
hooks-HASH.js gzip	635 B	635 B	✓
image-HASH.js gzip	4.49 kB	4.49 kB	✓
index-HASH.js gzip	263 B	263 B	✓
link-HASH.js gzip	1.87 kB	1.87 kB	-4 B
routerDirect..HASH.js gzip	321 B	321 B	✓
script-HASH.js gzip	383 B	383 B	✓
withRouter-HASH.js gzip	318 B	318 B	✓
85e02e95b279..7e3.css gzip	107 B	107 B	✓
Overall change	13.3 kB	13.3 kB	-4 B

Client Build Manifests

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
_buildManifest.js gzip	460 B	460 B	✓
Overall change	460 B	460 B	✓

Rendered Page Sizes Overall decrease ✓

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
index.html gzip	532 B	532 B	✓
link.html gzip	546 B	545 B	-1 B
withRouter.html gzip	527 B	527 B	✓
Overall change	1.6 kB	1.6 kB	-1 B

Diffs

Diff for _buildManifest.js

@@ -13,7 +13,7 @@ self.__BUILD_MANIFEST = {
   "/head": ["static\u002Fchunks\u002Fpages\u002Fhead-7100d3b2a548f0e4.js"],
   "/hooks": ["static\u002Fchunks\u002Fpages\u002Fhooks-ff60bc61acd2698b.js"],
   "/image": ["static\u002Fchunks\u002Fpages\u002Fimage-f207079640969086.js"],
-  "/link": ["static\u002Fchunks\u002Fpages\u002Flink-678af336607f5345.js"],
+  "/link": ["static\u002Fchunks\u002Fpages\u002Flink-b57fa5abc6a43d15.js"],
   "/routerDirect": [
     "static\u002Fchunks\u002Fpages\u002FrouterDirect-76232dd6bc335a24.js"
   ],

Diff for link-HASH.js

@@ -255,13 +255,14 @@
           }
         };
         childProps.onMouseEnter = function(e) {
-          if (!(0, _router).isLocalURL(href)) return;
           if (child.props && typeof child.props.onMouseEnter === "function") {
             child.props.onMouseEnter(e);
           }
-          prefetch(router, href, as, {
-            priority: true
-          });
+          if ((0, _router).isLocalURL(href)) {
+            prefetch(router, href, as, {
+              priority: true
+            });
+          }
         };
         // If child is an <a> tag and doesn't have a href attribute, or if the 'passHref' property is
         // defined, we specify the current 'href', so that repetition is not needed by the user

Diff for link.html

@@ -27,7 +27,7 @@
       defer=""
     ></script>
     <script
-      src="/_next/static/chunks/pages/link-678af336607f5345.js"
+      src="/_next/static/chunks/pages/link-b57fa5abc6a43d15.js"
       defer=""
     ></script>
     <script src="/_next/static/BUILD_ID/_buildManifest.js" defer=""></script>

---

Default Build with SWC (Increase detected ⚠️)

General Overall increase ⚠️

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
buildDuration	28.6s	28.2s	-326ms
buildDurationCached	4.7s	4.7s	-8ms
nodeModulesSize	347 MB	347 MB	⚠️ +25 B

Page Load Tests Overall increase ✓

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
/ failed reqs	0	0	✓
/ total time (seconds)	4.374	4.284	-0.09
/ avg req/sec	571.53	583.55	+12.02
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	2.324	2.245	-0.08
/error-in-render avg req/sec	1075.81	1113.79	+37.98

Client Bundles (main, webpack, commons)

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
450.HASH.js gzip	179 B	179 B	✓
framework-HASH.js gzip	42.3 kB	42.3 kB	✓
main-HASH.js gzip	28.6 kB	28.6 kB	✓
webpack-HASH.js gzip	1.44 kB	1.44 kB	✓
Overall change	72.5 kB	72.5 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages Overall decrease ✓

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
_app-HASH.js gzip	1.35 kB	1.35 kB	✓
_error-HASH.js gzip	180 B	180 B	✓
amp-HASH.js gzip	305 B	305 B	✓
css-HASH.js gzip	321 B	321 B	✓
dynamic-HASH.js gzip	2.37 kB	2.37 kB	✓
head-HASH.js gzip	342 B	342 B	✓
hooks-HASH.js gzip	622 B	622 B	✓
image-HASH.js gzip	4.53 kB	4.53 kB	✓
index-HASH.js gzip	256 B	256 B	✓
link-HASH.js gzip	1.91 kB	1.9 kB	-2 B
routerDirect..HASH.js gzip	314 B	314 B	✓
script-HASH.js gzip	375 B	375 B	✓
withRouter-HASH.js gzip	309 B	309 B	✓
85e02e95b279..7e3.css gzip	107 B	107 B	✓
Overall change	13.3 kB	13.3 kB	-2 B

Client Build Manifests

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
_buildManifest.js gzip	458 B	458 B	✓
Overall change	458 B	458 B	✓

Rendered Page Sizes

	vercel/next.js canary	ericmatthys/next.js external-link-mouse-enter	Change
index.html gzip	531 B	531 B	✓
link.html gzip	545 B	545 B	✓
withRouter.html gzip	525 B	525 B	✓
Overall change	1.6 kB	1.6 kB	✓

Diffs

Diff for _buildManifest.js

@@ -13,7 +13,7 @@ self.__BUILD_MANIFEST = {
   "/head": ["static\u002Fchunks\u002Fpages\u002Fhead-7100d3b2a548f0e4.js"],
   "/hooks": ["static\u002Fchunks\u002Fpages\u002Fhooks-ff60bc61acd2698b.js"],
   "/image": ["static\u002Fchunks\u002Fpages\u002Fimage-f207079640969086.js"],
-  "/link": ["static\u002Fchunks\u002Fpages\u002Flink-678af336607f5345.js"],
+  "/link": ["static\u002Fchunks\u002Fpages\u002Flink-b57fa5abc6a43d15.js"],
   "/routerDirect": [
     "static\u002Fchunks\u002Fpages\u002FrouterDirect-76232dd6bc335a24.js"
   ],

Diff for link-HASH.js

@@ -255,13 +255,14 @@
           }
         };
         childProps.onMouseEnter = function(e) {
-          if (!(0, _router).isLocalURL(href)) return;
           if (child.props && typeof child.props.onMouseEnter === "function") {
             child.props.onMouseEnter(e);
           }
-          prefetch(router, href, as, {
-            priority: true
-          });
+          if ((0, _router).isLocalURL(href)) {
+            prefetch(router, href, as, {
+              priority: true
+            });
+          }
         };
         // If child is an <a> tag and doesn't have a href attribute, or if the 'passHref' property is
         // defined, we specify the current 'href', so that repetition is not needed by the user

Diff for link.html

@@ -27,7 +27,7 @@
       defer=""
     ></script>
     <script
-      src="/_next/static/chunks/pages/link-678af336607f5345.js"
+      src="/_next/static/chunks/pages/link-b57fa5abc6a43d15.js"
       defer=""
     ></script>
     <script src="/_next/static/BUILD_ID/_buildManifest.js" defer=""></script>

Commit: b86fb43

[ijjk]

Change and test look good, thanks for the PR!