refactor(core,edges): add div based edge label renderer

packages/core/src/components/Edges/EdgeLabelRenderer.vue

@@ -0,0 +1,23 @@
+<script lang="ts" setup>
+import { useVueFlow } from '../../composables'
+
+const { viewportRef } = useVueFlow()
+
+const teleportTarget = $computed(() => viewportRef.value?.getElementsByClassName('vue-flow__edge-labels')[0])
+</script>
+
+<script lang="ts">
+export default {
+  name: 'EdgeLabelRenderer',
+}
+</script>
+
+<template>
+  <svg>
+    <foreignObject height="0" width="0">
+      <Teleport :to="teleportTarget" :disabled="!teleportTarget">
+        <slot />
+      </Teleport>
+    </foreignObject>
+  </svg>
+</template>

packages/core/src/components/Edges/EdgeText.vue

@@ -1,4 +1,5 @@
 <script lang="ts" setup>
+import { isString } from '@vueuse/core'
 import type { EdgeTextProps } from '../../types/components'
 import type { Rect as RectType } from '../../types'
 
@@ -55,10 +56,8 @@ export default {
     />
     <text v-bind="$attrs" ref="el" class="vue-flow__edge-text" :y="box.height / 2" dy="0.3em" :style="labelStyle">
       <slot>
-        <component :is="label" v-if="typeof label !== 'string' && typeof label" />
-        <template v-else>
-          {{ label }}
-        </template>
+        <component :is="label" v-if="!isString(label)" />
+        <template v-else> {{ label }} </template>
       </slot>
     </text>
   </g>

packages/core/src/components/Edges/index.ts

@@ -7,3 +7,4 @@ export { default as StraightEdge } from './StraightEdge'
 export { default as EdgeAnchor } from './EdgeAnchor'
 export { default as EdgeText } from './EdgeText.vue'
 export { default as EdgeWrapper } from './Wrapper'
+export { default as EdgeLabelRenderer } from './EdgeLabelRenderer.vue'

packages/core/src/container/EdgeRenderer/EdgeRenderer.vue

@@ -127,24 +127,27 @@ export default {
 </script>
 
 <template>
-  <svg v-for="group of groups" :key="group.level" class="vue-flow__edges vue-flow__container" :style="`z-index: ${group.level}`">
-    <MarkerDefinitions v-if="group.isMaxLevel" />
-    <g>
-      <EdgeWrapper
-        v-for="edge of group.edges"
-        :id="edge.id"
-        :key="edge.id"
-        :edge="edge"
-        :type="getType(edge.type, edge.template)"
-        :name="edge.type || 'default'"
-        :source-node="getNode(edge.source)"
-        :target-node="getNode(edge.target)"
-        :selectable="selectable(edge.selectable)"
-        :updatable="updatable(edge.updatable)"
-        :class="getClass(edge)"
-      />
-    </g>
-  </svg>
+  <template v-for="group of groups" :key="group.level">
+    <svg class="vue-flow__edges vue-flow__container" :style="`z-index: ${group.level}`">
+      <MarkerDefinitions v-if="group.isMaxLevel" />
+      <g>
+        <EdgeWrapper
+          v-for="edge of group.edges"
+          :id="edge.id"
+          :key="edge.id"
+          :edge="edge"
+          :type="getType(edge.type, edge.template)"
+          :name="edge.type || 'default'"
+          :source-node="getNode(edge.source)"
+          :target-node="getNode(edge.target)"
+          :selectable="selectable(edge.selectable)"
+          :updatable="updatable(edge.updatable)"
+          :class="getClass(edge)"
+        />
+      </g>
+    </svg>
+  </template>
+
   <svg v-if="connectionLineVisible && !!sourceNode" class="vue-flow__edges vue-flow__connectionline vue-flow__container">
     <ConnectionLine :source-node="sourceNode" />
   </svg>

packages/core/src/container/Viewport/Transform.vue

@@ -53,6 +53,9 @@ export default {
     :style="{ transform: `translate(${viewport.x}px,${viewport.y}px) scale(${viewport.zoom})`, opacity: ready ? undefined : 0 }"
   >
     <EdgeRenderer />
+
+    <div class="vue-flow__edge-labels" />
+
     <NodeRenderer />
     <slot />
   </div>

packages/core/src/index.ts

@@ -7,7 +7,16 @@ export { default as VueFlow } from './container/VueFlow/VueFlow.vue'
 
 export { default as Handle } from './components/Handle/Handle.vue'
 
-export { StraightEdge, StepEdge, BezierEdge, SimpleBezierEdge, SmoothStepEdge, BaseEdge, EdgeText } from './components/Edges'
+export {
+  StraightEdge,
+  StepEdge,
+  BezierEdge,
+  SimpleBezierEdge,
+  SmoothStepEdge,
+  BaseEdge,
+  EdgeText,
+  EdgeLabelRenderer,
+} from './components/Edges'
 
 export { getBezierPath, getSimpleBezierPath, getSmoothStepPath, getStraightPath } from './components/Edges/utils'
 

packages/core/src/style.css

@@ -39,6 +39,13 @@
   z-index: 5;
 }
 
+.vue-flow__edge-labels {
+  position: absolute;
+  width: 100%;
+  height: 100%;
+  pointer-events: none;
+}
+
 .vue-flow__nodesselection-rect:focus,
 .vue-flow__nodesselection-rect:focus-visible {
   outline: none;

packages/core/src/utils/graph.ts

@@ -106,7 +106,7 @@ export const parseEdge = (edge: Edge, defaults?: Partial<GraphEdge>): GraphEdge
         selectable: edge.selectable,
         data: shallowReactive(edge.data || {}),
         events: shallowReactive(edge.events || {}),
-        label: edge.label && !isString(edge.label) ? markRaw(edge.label) : undefined,
+        label: edge.label && !isString(edge.label) ? markRaw(edge.label) : edge.label,
         ...defaults,
       } as GraphEdge)
     : defaults