为啥我安装类型时没有解决类型错误？

Posted 2023-03-13

【中文标题】为啥我安装类型时没有解决类型错误？

【英文标题】：Why aren't type errors resolved when I install types?为什么我安装类型时没有解决类型错误？

【发布时间】：2020-07-01 00:09:35

【问题描述】：

我正在使用 Visual Studio 代码、typescript、eslint 和 Jasmine 编写单元测试。

在我安装 eslint 之前，我的代码编译并运行良好。安装 eslint 后，在运行 npx eslint 'tsc/**' 时出现错误，我在 Visual Studio 中也看到了这些错误。

其中一个错误是'describe' is not defined。由于这个功能来自 Jasmine，我意识到我需要安装 Jasmine 类型。我通过在命令行上输入以下内容来做到这一点：npm i -D @types/jasmine

安装类型后，当我在 eslint 和 Visual Studio 代码中运行命令行时，仍然会遇到这些错误。如果我打开 node_modules\@types\jasmine\index.d.ts 文件，我会在其中看到这一行：

/**
 * Create a group of specs (often called a suite).
 * @param description Textual description of the group
 * @param specDefinitions Function for Jasmine to invoke that will define inner suites a specs
 */
declare function describe(description: string, specDefinitions: () => void): void;

那么为什么 ESLint 仍然抱怨这些类型没有定义？我对所有这些技术都很陌生，所以我没有想法。

tsconfig.json：

  "compilerOptions": 
    /* Basic Options */
    // "incremental": true,                   /* Enable incremental compilation */
    "target": "es5",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', or 'ESNEXT'. */
    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */
    "lib": ["es6","dom"],                           /* Specify library files to be included in the compilation. */
    "allowJs": false,                         /* Allow javascript files to be compiled. */
    // "checkJs": true,                       /* Report errors in .js files. */
    // "jsx": "preserve",                     /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */
    // "declaration": true,                   /* Generates corresponding '.d.ts' file. */
    // "declarationMap": true,                /* Generates a sourcemap for each corresponding '.d.ts' file. */
    // "sourceMap": true,                     /* Generates corresponding '.map' file. */
    // "outFile": "./",                       /* Concatenate and emit output to single file. */
    "outDir": "tscbuild",                        /* Redirect output structure to the directory. */
    "rootDir": "tsc",                         /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
    // "composite": true,                     /* Enable project compilation */
    // "tsBuildInfoFile": "./",               /* Specify file to store incremental compilation information */
    // "removeComments": true,                /* Do not emit comments to output. */
    // "noEmit": true,                        /* Do not emit outputs. */
    // "importHelpers": true,                 /* Import emit helpers from 'tslib'. */
    // "downlevelIteration": true,            /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
    // "isolatedModules": true,               /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */

    /* Strict Type-Checking Options */
    "strict": true,                           /* Enable all strict type-checking options. */
    "noImplicitAny": true,                    /* Raise error on expressions and declarations with an implied 'any' type. */
    "strictNullChecks": true,              /* Enable strict null checks. */
    "strictFunctionTypes": true,           /* Enable strict checking of function types. */
    "strictBindCallApply": true,           /* Enable strict 'bind', 'call', and 'apply' methods on functions. */
    "strictPropertyInitialization": true,  /* Enable strict checking of property initialization in classes. */
    // "noImplicitThis": true,                /* Raise error on 'this' expressions with an implied 'any' type. */
    "alwaysStrict": true,                  /* Parse in strict mode and emit "use strict" for each source file. */

    /* Additional Checks */
    "noUnusedLocals": true,                /* Report errors on unused locals. */
    // "noUnusedParameters": true,            /* Report errors on unused parameters. */
    "noImplicitReturns": true,             /* Report error when not all code paths in function return a value. */
    "noFallthroughCasesInSwitch": true,    /* Report errors for fallthrough cases in switch statement. */

    /* Module Resolution Options */
    // "moduleResolution": "node",            /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
    // "baseUrl": "./",                       /* Base directory to resolve non-absolute module names. */
    // "paths": ,                           /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
    // "rootDirs": [],                        /* List of root folders whose combined content represents the structure of the project at runtime. */
    // "typeRoots": [],                       /* List of folders to include type definitions from. */
    // "types": [],                           /* Type declaration files to be included in compilation. */
    // "allowSyntheticDefaultImports": true,  /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
    "esModuleInterop": true,                  /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
    // "preserveSymlinks": true,              /* Do not resolve the real path of symlinks. */
    // "allowUmdGlobalAccess": true,          /* Allow accessing UMD globals from modules. */

    /* Source Map Options */
    // "sourceRoot": "",                      /* Specify the location where debugger should locate TypeScript files instead of source locations. */
    // "mapRoot": "",                         /* Specify the location where debugger should locate map files instead of generated locations. */
    // "inlineSourceMap": true,               /* Emit a single file with source maps instead of having a separate file. */
    // "inlineSources": true,                 /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */

    /* Experimental Options */
    // "experimentalDecorators": true,        /* Enables experimental support for ES7 decorators. */
    // "emitDecoratorMetadata": true,         /* Enables experimental support for emitting type metadata for decorators. */

    /* Advanced Options */
    "resolveJsonModule": true,                /* Include modules imported with '.json' extension */
    "forceConsistentCasingInFileNames": true  /* Disallow inconsistently-cased references to the same file. */
  

.eslintrc.js

module.exports = 
  env: 
    browser: true,
    es6: true,
    node: true
  ,
  extends: ["airbnb-base"],
  globals: 
    Atomics: "readonly",
    SharedArrayBuffer: "readonly"
  ,
  parser: "@typescript-eslint/parser",
  parserOptions: 
    ecmaVersion: 2018
  ,
  plugins: ["@typescript-eslint"],
  rules: 
    quotes: ["error", "double"],
  
;

我意识到错误可能在于我使用 Jasmine 的方式，所以这里是该文件的摘录：

import "jasmine";
import "./app";

console.log("spec");

describe("App", () => 
  describe("rest()", () => 
    it("should subtract actions remaining", () => 
      (global as any).State.variables.actions_remaining = 5;

      (global as any).setup.rest();

      expect((global as any).State.variables.actions_remaining).toBe(4);
    );

    it("will not let you go below zero actions remaining", () => 
      (global as any).State.variables.actions_remaining = 0;

      (global as any).setup.rest();

      expect((global as any).State.variables.actions_remaining).toBe(0);
    );

【参考方案1】：

好的，我可以通过更改测试来消除这些错误：

import * as j from "jasmine";
import "./app";

console.log("spec");

j.describe("App", () => 
  j.describe("rest()", () => 
    j.it("should subtract actions remaining", () => 
      (global as any).State.variables.actions_remaining = 5;

      (global as any).setup.rest();

      j.expect((global as any).State.variables.actions_remaining).toBe(4);
    );

    j.it("will not let you go below zero actions remaining", () => 
      (global as any).State.variables.actions_remaining = 0;

      (global as any).setup.rest();

      j.expect((global as any).State.variables.actions_remaining).toBe(0);
    );

当您不使用 ESLint 时，可以将 Jasmine 函数用作全局函数。但要编译它，我必须参考 Jasmine 导入。

有没有办法避免这种情况，这样我就不必在每个 Jasmine 函数前加上 j. 并且仍然可以获得类型安全的所有好处？

【讨论】：

如果你使用import describe from "jasmine";?

@Silvermind 这是一个更好的解决方法：***.com/questions/60764680/…

好的。没问题。祝你好运。