https://code.visualstudio.com/blogs/2017/02/12/code-lens-roundup
https://marketplace.visualstudio.com/items?itemName=abierbaum.vscode-file-peek
https://github.com/xxMUROxx/vscode.code_call_lens/blob/master/src/extension.ts
https://code.visualstudio.com/docs/extensionAPI/language-support#_codelens-show-actionable-context-information-within-source-code
https://marketplace.visualstudio.com/items?itemName=waderyan.code-lens-roundup
https://mp.csdn.net/mdeditor#
https://pub.dartlang.org/documentation/vscode/latest/vscode/CodeLens-class.html
https://www.google.com.sg/search?rlz=1C1GCEU_zh-CNMY820MY820&biw=1600&bih=709&ei=mEfYW7jWD6i2ggeDl7_YDw&q=codeLens.method&oq=codeLens.method&gs_l=psy-ab.3...84573.84573.0.85474.1.1.0.0.0.0.353.353.3-1.1.0....0...1c.1.64.psy-ab..0.0.0....0.FSpszPXfY_w
https://intellij-support.jetbrains.com/hc/en-us/community/posts/206863215-Implement-CodeLens-in-the-code-editor
https://github.com/Microsoft/vscode/commit/770ede158afea0293f4c66448e0effb8d2788a4b
It depends on how complex your code lenses are to compute.
If the code lenses are very simple and can always be created in a fixed amount of time, you only need to implement provideCodeLens.
If creating the code lenses may involve intensive computation or any sort of non-deterministic behavior – such as network – then provideCodeLens should only return skeleton Code Lenses with ranges. You would then complete the CodeLens’ command in resolveCodeLens, which will only be called when the CodeLens actually needs to be displayed.
Overall, splitting your CodeLens implementation between provideCodeLenses and resolveCodeLens is the safest choice.
======================================================================
CodeLens
A code lens represents a command that should be shown along with source text, like the number of references, a way to run tests, etc.
A code lens is unresolved when no command is associated to it. For performance reasons the creation of a code lens and resolving should be done to two stages:“CodeLensProvider.provideCodeLenses” and “CodeLensProvider.resolveCodeLens”
参数说明：
command ↔ Command
The command this code lens represents.
isResolved ↔ bool true when there is a command associated. @readonly range ↔ Range The range in which this code lens is valid. Should only span a single line.
CodeLensProvider:
A code lens provider adds commands to source text. The commands will be shown as dedicated horizontal lines in between the source text.
一个扩展codelens的例子：
// The module 'vscode' contains the VS Code extensibility API import * as vscode from 'vscode'; export function activate(context: vscode.ExtensionContext) { console.log('Congratulations, your extension "my-extension2" is now active!'); var disposable1 = vscode.commands.registerCommand('extension.sayHello', () => { console.log("searchData"); }); // var s1 = vscode.languages.registerCodeLensProvider({scheme: 'file', language: 'csharp'}, { // provideCodeLenses: (doc, ct) => { // console.log('provideCodeLenses1'); // var codeLenses: vscode.CodeLens[] = []; // codeLenses.push( { // range: doc.lineAt(0).range, // // command: '', // isResolved: true // }); // return codeLenses; // }, // resolveCodeLens: (codeLens: vscode.CodeLens, token: vscode.CancellationToken) => { // return codeLens; // } // }); var s1 = vscode.languages.registerCodeLensProvider({scheme: 'file', language: 'csharp'}, { provideCodeLenses(document, token) { const result: vscode.CodeLens[] = []; let idx = -1; let count = 0; while ((idx = document.getText().indexOf('abc', idx + 1)) >= 0) { count ++ ; } while ((idx = document.getText().indexOf('abc', idx + 1)) >= 0) { const pos = document.positionAt(idx); const range = document.getWordRangeAtPosition(pos); const titleInfo = (count === 1 ? `${count} reference` : `${count} references`); result.push(new vscode.CodeLens(range, { title: titleInfo, command: 'extension.sayHello', arguments: ["123", "456", "789"]})); } return result; }, resolveCodeLens: (codeLens: vscode.CodeLens, token: vscode.CancellationToken) => { return codeLens; }, }); var s2 = vscode.languages.registerCodeLensProvider({ pattern: '**/*.abc' }, { provideCodeLenses(document, token) { const result: vscode.CodeLens[] = []; let idx = -1; let count = 0; while ((idx = document.getText().indexOf('abc', idx + 1)) >= 0) { count ++ ; } while ((idx = document.getText().indexOf('abc', idx + 1)) >= 0) { const pos = document.positionAt(idx); const range = document.getWordRangeAtPosition(pos); const titleInfo = (count === 1 ? `${count} reference` : `${count} references`); result.push(new vscode.CodeLens(range, { title: titleInfo, command: 'extension.sayHello', arguments: ["abc abc abc"] })); } return result; }, resolveCodeLens: (codeLens: vscode.CodeLens, token: vscode.CancellationToken) => { codeLens.command.command = 'extension.sayHello'; codeLens.command.arguments = ["aaa bbb ccc"]; return codeLens; } }); context.subscriptions.push(s1); context.subscriptions.push(s2); context.subscriptions.push(disposable1); }
显示效果：
github有许多开源项目，可以在上面找相关项目参考。
