tsconfig_base.jsonc

// A base tsconfig to be inherited (or used directly if component is for both browser and Node)
// NOTE vscode will warn about trailing commas in this file, but can ignore the warnings

{
    "$schema": "https://json.schemastore.org/tsconfig",
    "exclude": ["**/*.test.ts"],
    "compilerOptions": {

        // May need overriding
        "lib": ["ESNext"],  // Allow using latest JS features (add DOM & DOM.Iterable if browser)
        "types": [],  // Disables auto-including types modules of '@types/*' (add "node" if Node)

        // Language expectations
        "module": "ESNext",  // Default to ESM and override manually when building for CJS
        "target": "ESNext",  // Manually specify target for each build type
        "moduleResolution": "Node",  // All should use node-like module resolution, not just node

        // Other compilation settings
        "declaration": true,  // Emit declaration files
        "resolveJsonModule": true,  // Import JSON as objects
        "esModuleInterop": true,  // Make require imports work like es6 ones do
        "experimentalDecorators": true,  // Allow @decorators
        "skipLibCheck": true,  // Mostly avoids checking node_modules (but see docs)
        "jsx": "preserve",  // Volar needs for typechecking pug templates (for some reason)

        // Strict checking
        "strict": true,
        "allowUnreachableCode": false,  // Must be a mistake
        "allowUnusedLabels": false,  // Labels as in `continue *label*` for loops etc
        "exactOptionalPropertyTypes": true,  // {a:undefined} !== {}
        "noImplicitOverride": true,  // Must use `override` to make overriding parent class clear
        "noImplicitReturns": true,  // Must return a value unless void
        "noPropertyAccessFromIndexSignature": true,  // Must use `['a']` not `.a` if props unknown
        "noUncheckedIndexedAccess": true,  // If {[k:any]:type} consider `.k` = type|undefined
        "noUnusedLocals": true,  // Can't define variable and not use it
        "noUnusedParameters": false,  // It's ok to specify listener(event) and not use event
    },
}