fix

d2oracle/edit.go

@@ -500,7 +500,11 @@ func _set(g *d2graph.Graph, baseAST *d2ast.Map, key string, tag, value *string)
 			refs = GetWriteableEdgeRefs(edge, baseAST)
 		}
 		onlyInChain := true
-		for _, ref := range refs {
+		var earliestRef *d2graph.EdgeReference
+		for i, ref := range refs {
+			if earliestRef == nil || ref.MapKey.Range.Before(earliestRef.MapKey.Range) {
+				earliestRef = &refs[i]
+			}
 			// TODO merge flat edgekeys
 			// E.g. this can group into a map
 			// (y -> z)[0].style.opacity: 0.4
@@ -526,7 +530,15 @@ func _set(g *d2graph.Graph, baseAST *d2ast.Map, key string, tag, value *string)
 			}
 		}
 		if onlyInChain {
-			appendMapKey(scope, mk)
+			if earliestRef != nil && scope.Range.Before(earliestRef.MapKey.Range) {
+				// Since the original mk was trimmed to common, we set to the edge that
+				// the ref's scope is in
+				mk.Edges[0] = earliestRef.Edge
+				// We can't reference an edge before it's been defined
+				earliestRef.Scope.InsertAfter(earliestRef.MapKey, mk)
+			} else {
+				appendMapKey(scope, mk)
+			}
 			return nil
 		}
 		attrs = edge.Attributes

d2oracle/edit_test.go

@@ -2457,7 +2457,7 @@ a -> b
 `,
 		},
 		{
-			name: "nested-edge-chained",
+			name: "nested-edge-chained/1",
 
 			text: `a: {
   b: {
@@ -2477,6 +2477,31 @@ x -> a.b -> a.b.c
 
 x -> a.b -> a.b.c
 (a.b -> a.b.c)[0].style.stroke: green
+`,
+		},
+		{
+			name: "nested-edge-chained/2",
+
+			text: `z: {
+  a: {
+    b: {
+      c
+    }
+  }
+  x -> a.b -> a.b.c
+}
+`,
+			key:   `(z.a.b -> z.a.b.c)[0].style.stroke`,
+			value: go2.Pointer(`green`),
+			exp: `z: {
+  a: {
+    b: {
+      c
+    }
+  }
+  x -> a.b -> a.b.c
+  (a.b -> a.b.c)[0].style.stroke: green
+}
 `,
 		},
 	}