⚡ perf(vscode): 代码阅读预览发给页面的块只记相对位置：块在源码里占的地方记成离前一块多远、自己多长，块里名字的下标从块的开头算，页面从文件开头累加回文件里的位置、和扩展端打交道的地方都在一处换算；靠前改了代码，后面内容没变的块发过去一模一样，扩展端自己的块和发给页面的块分成两种类型

vscode/webview-ui/src/codeReader/CodeEditor.tsx

@@ -1,6 +1,6 @@
 import type { ChangeEvent, KeyboardEvent, ReactElement } from 'react'
 import type { SourceText } from './blockSource'
-import type { BlockView } from './types'
+import type { Place } from './placement'
 import { useEffect, useLayoutEffect, useMemo, useRef, useState } from 'react'
 import { blockSource } from './blockSource'
 import { recolor } from './segments'
@@ -10,9 +10,10 @@ import { postMessage } from './vscode'
 const EDIT_DEBOUNCE_MS = 200
 
 interface CodeEditorProps {
-  block: BlockView
   /** 这一版文档的源码和着色：这块的源码按它的编辑范围从里面取 */
   sourceText: SourceText
+  /** 这块在这一版文档里的位置：编辑范围是它的首尾行 */
+  place: Place
   /** 文档版本：每来一份新文档都要对一次输入框内容，哪怕这一块的代码没变 */
   version: number
   autoFocus: boolean
@@ -21,12 +22,12 @@ interface CodeEditorProps {
 }
 
 /** 一块源码的编辑状态：着色层显示，透明输入框接收输入，改动防抖后整行替换回文件。 */
-export function CodeEditor({ block, sourceText, version, autoFocus, onAutoFocused, onExit }: CodeEditorProps): ReactElement {
-  const { code, tokens } = useMemo(() => blockSource(sourceText, block.startLine, block.endLine), [sourceText, block.startLine, block.endLine])
+export function CodeEditor({ sourceText, place, version, autoFocus, onAutoFocused, onExit }: CodeEditorProps): ReactElement {
+  const { code, tokens } = useMemo(() => blockSource(sourceText, place.line, place.endLine), [sourceText, place.line, place.endLine])
   const [text, setText] = useState(code)
   const textareaRef = useRef<HTMLTextAreaElement>(null)
-  const blockRef = useRef(block)
-  blockRef.current = block
+  const placeRef = useRef(place)
+  placeRef.current = place
   const textRef = useRef(text)
   textRef.current = text
   /** 本地改过、还没在新文档里看到的文字；有它时新文档不能覆盖有焦点的输入框 */
@@ -42,12 +43,12 @@ export function CodeEditor({ block, sourceText, version, autoFocus, onAutoFocuse
     if (!unsent.current)
       return
     unsent.current = false
-    const { startLine, endLine } = blockRef.current
+    const { line, endLine } = placeRef.current
     const value = textRef.current
     postMessage({
       type: 'edit',
-      startLine,
-      endLine: sentLineCount.current === null ? endLine : startLine + sentLineCount.current - 1,
+      startLine: line,
+      endLine: sentLineCount.current === null ? endLine : line + sentLineCount.current - 1,
       text: value,
     })
     sentLineCount.current = value.split('\n').length