如何在实施 Go To Definition 时获取当前 text/symbol

Question

我正在使用语言服务器协议开发我的第一个 vscode 扩展，我需要在 Right click -> Go to definition 被触发时获取文本

我当前的 onDefinition 方法仅接收 textPosition

export default class DefinitionFinder extends Handler {
    constructor(
        protected connection: Connection,
        private refManager: ReferenceManager)
    {
        super();

        this.connection.onDefinition(async (textPosition) => {
            return this.handleErrors(
                this.getDefinition(textPosition), undefined) as Promise<Definition>;
        });
    }
    
private async getDefinition(textPosition: TextDocumentPositionParams): Promise<Location[]> {
    const text = "funABC";

    // instead of hardcoded value I need to get the text/symbol 
    // that is going to be use to go to definition 

    return this.refManager.getDefinitionLocations(text);
}

TextDocumentPositionParams只包含documentUri、line(number)和character(number)

这是否意味着每次调用 onDefinition 我都需要打开文档，转到行和字符并获取当前单词？

export interface TextDocumentPositionParams {
    /**
     * The text document.
     */
    textDocument: TextDocumentIdentifier;
    /**
     * The position inside the text document.
     */
    position: Position;
}

export interface TextDocumentIdentifier {
    /**
     * The text document's uri. (string)
     */
    uri: DocumentUri;
}

export declare namespace Position {
    /**
     * Creates a new Position literal from the given line and character.
     * @param line The position's line.
     * @param character The position's character.
     */

Answer 1

语言服务器通常会根据收到的文档更改事件维护一个文本文档缓存。如果您使用 TypeScript 编写语言服务器，则可以简单地使用 vscode-languageserver 和 vscode-languageserver-textdocument 包中的实现。相关摘录自official sample：

import { TextDocuments } from 'vscode-languageserver';
import { TextDocument } from 'vscode-languageserver-textdocument';

// Create a simple text document manager.
const documents: TextDocuments<TextDocument> = new TextDocuments(TextDocument);

...

// Make the text document manager listen on the connection
// for open, change and close text document events
documents.listen(connection);

那么你可以这样做：

documents.get(uri).getText(range)

Answer 2

在我的例子中，我实现了这个：

let word = document.getText(document.getWordRangeAtPosition(position));

这适用于扩展 API

Answer 3

当在语言服务器上请求“转到定义”

时，这就是我最终实现逻辑以获取 word/symbol 的方式

我决定 return 一个 LocationLink，它也显示为 word/symbol

上的超链接

this.connection.onDefinition(async (textPosition) => {
    return this.handleErrors(
        this.getDefinitionLink(textPosition), undefined) as Promise<LocationLink[]>;
});

此方法从文档中获取符号，然后在 refManager 中查看其定义

private async getDefinitionLink(textPosition: TextDocumentPositionParams): Promise<LocationLink[]> {
    const symbol = this.getSymbolAtPosition(textPosition.position, textPosition.textDocument.uri);

    return this.refManager.getDefinitionLink(symbol);
}

这是提取当前单词的实际逻辑，无论它是否在中间单击。


let TokenSeparatorsXML = /[\t= <>"]/;

public getSymbolAtPosition(position: Position, documentUri: string): string {
    const range = {
        start: { line: position.line, character: 0},
        end: { line: position.line, character: Number.MAX_VALUE  }
    };
    //get the whole line 
    const txtDoc = this.refManager.getDocument(documentUri)!;

    const context = txtDoc.getText(range);
    const offset = position.character ;

    let start = offset-1;

    while ((start > 0) && !context[start].match(this.TokenSeparatorsXML))
    {
        start--;
    }

    let end = offset;

    while ((end < context.length) && !context[end].match(this.TokenSeparatorsXML))
    {
        end++;
    }

    const symbol = context.substr(start + 1, end - start - 1);

    console.log(`${start}->${end}- symbol: ${symbol}`);

    return symbol;
}

在我的例子中，令牌分隔符非常窄，但您应该考虑使用单词模式 https://code.visualstudio.com/api/language-extensions/language-configuration-guide#word-pattern

可以在此处找到扩展的完整代码 - https://github.com/mauriciogracia/petrel-xml

如何在实施 Go To Definition 时获取当前 text/symbol

How to get current text/symbol when implementing Go To Definition

typescript

visual-studio-code

vscode-extensions

language-server-protocol