refactor(compiler): use symbols for runtime helpers

packages/compiler-core/src/runtimeHelpers.ts

@@ -0,0 +1,64 @@
+export const FRAGMENT = Symbol()
+export const PORTAL = Symbol()
+export const COMMENT = Symbol()
+export const TEXT = Symbol()
+export const SUSPENSE = Symbol()
+export const EMPTY = Symbol()
+export const OPEN_BLOCK = Symbol()
+export const CREATE_BLOCK = Symbol()
+export const CREATE_VNODE = Symbol()
+export const RESOLVE_COMPONENT = Symbol()
+export const RESOLVE_DIRECTIVE = Symbol()
+export const APPLY_DIRECTIVES = Symbol()
+export const RENDER_LIST = Symbol()
+export const RENDER_SLOT = Symbol()
+export const CREATE_SLOTS = Symbol()
+export const TO_STRING = Symbol()
+export const MERGE_PROPS = Symbol()
+export const TO_HANDLERS = Symbol()
+export const CAMELIZE = Symbol()
+
+export type RuntimeHelper =
+  | typeof FRAGMENT
+  | typeof PORTAL
+  | typeof COMMENT
+  | typeof TEXT
+  | typeof SUSPENSE
+  | typeof EMPTY
+  | typeof OPEN_BLOCK
+  | typeof CREATE_BLOCK
+  | typeof CREATE_VNODE
+  | typeof RESOLVE_COMPONENT
+  | typeof RESOLVE_DIRECTIVE
+  | typeof APPLY_DIRECTIVES
+  | typeof RENDER_LIST
+  | typeof RENDER_SLOT
+  | typeof CREATE_SLOTS
+  | typeof TO_STRING
+  | typeof MERGE_PROPS
+  | typeof TO_HANDLERS
+  | typeof CAMELIZE
+
+// Name mapping for runtime helpers that need to be imported from 'vue' in
+// generated code. Make sure these are correctly exported in the runtime!
+export const helperNameMap = {
+  [FRAGMENT]: `Fragment`,
+  [PORTAL]: `Portal`,
+  [COMMENT]: `Comment`,
+  [TEXT]: `Text`,
+  [SUSPENSE]: `Suspense`,
+  [EMPTY]: `Empty`,
+  [OPEN_BLOCK]: `openBlock`,
+  [CREATE_BLOCK]: `createBlock`,
+  [CREATE_VNODE]: `createVNode`,
+  [RESOLVE_COMPONENT]: `resolveComponent`,
+  [RESOLVE_DIRECTIVE]: `resolveDirective`,
+  [APPLY_DIRECTIVES]: `applyDirectives`,
+  [RENDER_LIST]: `renderList`,
+  [RENDER_SLOT]: `renderSlot`,
+  [CREATE_SLOTS]: `createSlots`,
+  [TO_STRING]: `toString`,
+  [MERGE_PROPS]: `mergeProps`,
+  [TO_HANDLERS]: `toHandlers`,
+  [CAMELIZE]: `camelize`
+}