fix(compiler-core): only merge true handlers (#4577)

HerringtonDarkholme · web-flow · commit d8a36d0198a4 · 2021-09-21T12:37:51.000-04:00
diff --git a/packages/compiler-core/src/transforms/transformElement.ts b/packages/compiler-core/src/transforms/transformElement.ts
@@ -807,7 +807,7 @@ function dedupeProperties(properties: Property[]): Property[] {
     const name = prop.key.content
     const existing = knownProps.get(name)
     if (existing) {
-      if (name === 'style' || name === 'class' || name.startsWith('on')) {
+      if (name === 'style' || name === 'class' || isOn(name)) {
         mergeAsArray(existing, prop)
       }
       // unexpected duplicate, should have emitted error during parse

Original file line number	Diff line number	Diff line change
`@@ -807,7 +807,7 @@ function dedupeProperties(properties: Property[]): Property[] {`
`807`	`807`	`const name = prop.key.content`
`808`	`808`	`const existing = knownProps.get(name)`
`809`	`809`	`if (existing) {`
`810`		`- if (name === 'style' \|\| name === 'class' \|\| name.startsWith('on')) {`
	`810`	`+ if (name === 'style' \|\| name === 'class' \|\| isOn(name)) {`
`811`	`811`	`mergeAsArray(existing, prop)`
`812`	`812`	`}`
`813`	`813`	`// unexpected duplicate, should have emitted error during parse`