chore: improve internal tsconfig options for improved dx

eslint.config.ts

@@ -1,19 +1,48 @@
-import type { Linter } from "eslint";
-
-import comments from "@eslint-community/eslint-plugin-eslint-comments/configs";
 import eslint from "@eslint/js";
 import markdown from "@eslint/markdown";
+import comments from "@eslint-community/eslint-plugin-eslint-comments/configs";
 import vitest from "@vitest/eslint-plugin";
+import type { Linter } from "eslint";
+import { defineConfig, globalIgnores } from "eslint/config";
 import jsdoc from "eslint-plugin-jsdoc";
 import jsonc from "eslint-plugin-jsonc";
 import n from "eslint-plugin-n";
 import packageJson from "eslint-plugin-package-json";
 import perfectionist from "eslint-plugin-perfectionist";
+import { Alphabet } from "eslint-plugin-perfectionist/alphabet";
 import * as regexp from "eslint-plugin-regexp";
 import yml from "eslint-plugin-yml";
-import { defineConfig, globalIgnores } from "eslint/config";
 import tseslint from "typescript-eslint";
 
+const importAlphabet = Alphabet.generateRecommendedAlphabet()
+	.sortByNaturalSort()
+	.placeCharacterBefore({ characterAfter: "-", characterBefore: "/" })
+	.placeCharacterBefore({ characterAfter: "/", characterBefore: "." })
+	.getCharacters();
+
+// https://typescript-eslint.io/troubleshooting/typed-linting/performance#importextensions-enforcing-extensions-are-not-used
+function banJsImportExtension() {
+	const message = `Unexpected use of .js file extension (.js) in import; please use .ts`;
+	const literalAttributeMatcher = `Literal[value=/\\.js$/]`;
+	return [
+		{
+			message,
+			// import foo from 'bar.js';
+			selector: `ImportDeclaration > ${literalAttributeMatcher}.source`,
+		},
+		{
+			message,
+			// export { foo } from 'bar.js';
+			selector: `ExportNamedDeclaration > ${literalAttributeMatcher}.source`,
+		},
+		{
+			message,
+			// type Foo = typeof import('bar.js');
+			selector: `TSImportType > TSLiteralType > ${literalAttributeMatcher}`,
+		},
+	];
+}
+
 export default defineConfig(
 	globalIgnores([
 		"**/*.snap",
@@ -47,6 +76,7 @@ export default defineConfig(
 			},
 		},
 		rules: {
+			"@typescript-eslint/no-import-type-side-effects": "error",
 			"@typescript-eslint/no-unnecessary-condition": [
 				"error",
 				{ allowConstantLoopConditions: true },
@@ -73,6 +103,24 @@ export default defineConfig(
 
 			// https://github.com/eslint-community/eslint-plugin-n/issues/472
 			"n/no-unpublished-bin": "off",
+
+			"no-restricted-syntax": ["error", ...banJsImportExtension()],
+
+			"perfectionist/sort-imports": [
+				"error",
+				{
+					alphabet: importAlphabet,
+					groups: [
+						"side-effect",
+						["builtin", "external"],
+						["parent", "sibling", "index", "subpath"],
+						"unknown",
+					],
+
+					partitionByNewLine: false,
+					type: "custom",
+				},
+			],
 		},
 		settings: {
 			n: {

package.json

@@ -15,7 +15,7 @@
 	"type": "module",
 	"scripts": {
 		"build": "tsdown",
-		"flint": "node packages/flint/bin/index.js",
+		"flint": "node --conditions='@flint.fyi/source' packages/flint/bin/index.js",
 		"lint": "eslint . --max-warnings 0",
 		"lint:knip": "knip",
 		"lint:packages": "pnpm dedupe --check",

packages/cli/src/formatting/runPrettier.ts

@@ -1,4 +1,4 @@
-import {
+import type {
 	FormattingResults,
 	LintResultsMaybeWithChanges,
 } from "@flint.fyi/core";

packages/cli/src/index.ts

@@ -1 +1 @@
-export { runCli } from "./runCli.js";
+export { runCli } from "./runCli.ts";

packages/cli/src/options.ts

@@ -1,4 +1,4 @@
-import { parseArgs, ParseArgsOptionsConfig } from "node:util";
+import type { parseArgs, ParseArgsOptionsConfig } from "node:util";
 
 export const options = {
 	"cache-ignore": {

packages/cli/src/presenters/briefPresenterFactory.ts

@@ -3,10 +3,10 @@ import { makeAbsolute } from "@flint.fyi/utils";
 import { styleText } from "node:util";
 import { textTable } from "text-table-fast";
 
-import { presentHeader } from "./shared/header.js";
-import { presentDiagnostics } from "./shared/presentDiagnostics.js";
-import { presentSummary } from "./shared/summary.js";
-import { PresenterFactory } from "./types.js";
+import { presentHeader } from "./shared/header.ts";
+import { presentDiagnostics } from "./shared/presentDiagnostics.ts";
+import { presentSummary } from "./shared/summary.ts";
+import type { PresenterFactory } from "./types.ts";
 
 export const briefPresenterFactory: PresenterFactory = {
 	about: {

packages/cli/src/presenters/detailed/constants.ts

@@ -2,17 +2,17 @@ import chalk from "chalk";
 
 export const indenter = chalk.gray("│ ");
 
-export enum ColorCodes {
-	codeLineNumbers = "#bbb",
-	codeWarningUnderline = "#fcc",
-	defaultSuggestionColor = "#bbccdd",
-	filePath = "#ff4949",
-	filePathPrefix = "#ff7777",
-	primaryMessage = "#eeaa77",
-	reportAboutId = "#ff9999",
-	ruleBracket = "#ccaaaa",
-	ruleUrl = "#aaccaa",
-	secondaryMessage = "#ccbbaa",
-	suggestionMessage = "#99aacc",
-	suggestionTextHighlight = "#bbeeff",
-}
+export const ColorCodes = {
+	codeLineNumbers: "#bbb",
+	codeWarningUnderline: "#fcc",
+	defaultSuggestionColor: "#bbccdd",
+	filePath: "#ff4949",
+	filePathPrefix: "#ff7777",
+	primaryMessage: "#eeaa77",
+	reportAboutId: "#ff9999",
+	ruleBracket: "#ccaaaa",
+	ruleUrl: "#aaccaa",
+	secondaryMessage: "#ccbbaa",
+	suggestionMessage: "#99aacc",
+	suggestionTextHighlight: "#bbeeff",
+} as const;

packages/cli/src/presenters/detailed/createDetailedReport.ts

@@ -1,10 +1,10 @@
-import { FileReport } from "@flint.fyi/core";
+import type { FileReport } from "@flint.fyi/core";
 import chalk from "chalk";
 
-import { ColorCodes, indenter } from "./constants.js";
-import { formatCode } from "./formatCode.js";
-import { formatSuggestion } from "./formatSuggestion.js";
-import { wrapIfNeeded } from "./wrapIfNeeded.js";
+import { ColorCodes, indenter } from "./constants.ts";
+import { formatCode } from "./formatCode.ts";
+import { formatSuggestion } from "./formatSuggestion.ts";
+import { wrapIfNeeded } from "./wrapIfNeeded.ts";
 
 export async function* createDetailedReport(
 	report: FileReport,

packages/cli/src/presenters/detailed/detailedPresenterFactory.ts

@@ -1,13 +1,13 @@
 import { hasFix } from "@flint.fyi/core";
 import chalk from "chalk";
 
-import { presentHeader } from "../shared/header.js";
-import { presentDiagnostics } from "../shared/presentDiagnostics.js";
-import { presentSummary } from "../shared/summary.js";
-import { PresenterFactory } from "../types.js";
-import { ColorCodes, indenter } from "./constants.js";
-import { createDetailedReport } from "./createDetailedReport.js";
-import { wrapIfNeeded } from "./wrapIfNeeded.js";
+import { presentHeader } from "../shared/header.ts";
+import { presentDiagnostics } from "../shared/presentDiagnostics.ts";
+import { presentSummary } from "../shared/summary.ts";
+import type { PresenterFactory } from "../types.ts";
+import { ColorCodes, indenter } from "./constants.ts";
+import { createDetailedReport } from "./createDetailedReport.ts";
+import { wrapIfNeeded } from "./wrapIfNeeded.ts";
 
 export const detailedPresenterFactory: PresenterFactory = {
 	about: {

packages/cli/src/presenters/detailed/formatCode.ts

@@ -1,9 +1,9 @@
-import { FileReport } from "@flint.fyi/core";
+import type { FileReport } from "@flint.fyi/core";
 import * as shikiCli from "@shikijs/cli";
 import chalk from "chalk";
 import { styleText } from "node:util";
 
-import { ColorCodes, indenter } from "./constants.js";
+import { ColorCodes, indenter } from "./constants.ts";
 
 // TODO: make reactive
 const leftWidth = 7;

packages/cli/src/presenters/detailed/formatSuggestion.ts

@@ -1,6 +1,6 @@
 import chalk from "chalk";
 
-import { ColorCodes } from "./constants.js";
+import { ColorCodes } from "./constants.ts";
 
 export function formatSuggestion(suggestion: string) {
 	return [

packages/cli/src/presenters/detailed/wrapIfNeeded.ts

@@ -1,7 +1,7 @@
-import { ChalkInstance } from "chalk";
+import type { ChalkInstance } from "chalk";
 import wrapAnsi from "wrap-ansi";
 
-import { indenter } from "./constants.js";
+import { indenter } from "./constants.ts";
 
 export function wrapIfNeeded(
 	lineFormat: ChalkInstance,

packages/cli/src/presenters/getPresenterFactory.ts

@@ -1,7 +1,7 @@
-import { OptionsValues } from "../options.js";
-import { briefPresenterFactory } from "./briefPresenterFactory.js";
-import { detailedPresenterFactory } from "./detailed/detailedPresenterFactory.js";
-import { PresenterFactory } from "./types.js";
+import type { OptionsValues } from "../options.ts";
+import { briefPresenterFactory } from "./briefPresenterFactory.ts";
+import { detailedPresenterFactory } from "./detailed/detailedPresenterFactory.ts";
+import type { PresenterFactory } from "./types.ts";
 
 export function getPresenterFactory(
 	values: Pick<OptionsValues, "interactive" | "presenter">,

packages/cli/src/presenters/shared/header.ts

@@ -2,7 +2,7 @@ import { cacheFilePath } from "@flint.fyi/core";
 import chalk from "chalk";
 import fs from "node:fs";
 
-import { PresenterInitializeContext } from "../types.js";
+import type { PresenterInitializeContext } from "../types.ts";
 
 export function* presentHeader({
 	configFileName,

packages/cli/src/presenters/shared/presentDiagnostics.ts

@@ -1,7 +1,7 @@
-import { FileResults } from "@flint.fyi/core";
+import type { FileResults } from "@flint.fyi/core";
 import { styleText } from "node:util";
 
-import { pluralize } from "../pluralize.js";
+import { pluralize } from "../pluralize.ts";
 
 export function* presentDiagnostics(filesResults: Map<string, FileResults>) {
 	const diagnostics = Array.from(filesResults.values()).flatMap(

packages/cli/src/presenters/shared/summary.ts

@@ -1,7 +1,7 @@
 import { styleText } from "node:util";
 
-import { pluralize } from "../pluralize.js";
-import { PresenterSummarizeContext } from "../types.js";
+import { pluralize } from "../pluralize.ts";
+import type { PresenterSummarizeContext } from "../types.ts";
 
 export interface SummaryCounts {
 	all: number;

packages/cli/src/renderers/createRendererFactory.ts

@@ -1,7 +1,7 @@
-import { OptionsValues } from "../options.js";
-import { getPresenterFactory } from "../presenters/getPresenterFactory.js";
-import { interactiveRendererFactory } from "./interactive/interactiveRendererFactory.js";
-import { singleRendererFactory } from "./singleRendererFactory.js";
+import type { OptionsValues } from "../options.ts";
+import { getPresenterFactory } from "../presenters/getPresenterFactory.ts";
+import { interactiveRendererFactory } from "./interactive/interactiveRendererFactory.ts";
+import { singleRendererFactory } from "./singleRendererFactory.ts";
 
 export function createRendererFactory(
 	configFileName: string,

packages/cli/src/renderers/interactive/interactiveRendererFactory.ts

@@ -1,14 +1,14 @@
 import cliCursor from "cli-cursor";
 import readline from "node:readline";
 
-import { RendererContext, RendererFactory } from "../types.js";
-import { createListeners } from "./createListeners.js";
-import { createState } from "./createState.js";
-import { printAllClear } from "./printAllClear.js";
-import { printControls } from "./printControls.js";
-import { printFile } from "./printFile.js";
-import { printHeader } from "./printHeader.js";
-import { printSummary } from "./printSummary.js";
+import type { RendererContext, RendererFactory } from "../types.ts";
+import { createListeners } from "./createListeners.ts";
+import { createState } from "./createState.ts";
+import { printAllClear } from "./printAllClear.ts";
+import { printControls } from "./printControls.ts";
+import { printFile } from "./printFile.ts";
+import { printHeader } from "./printHeader.ts";
+import { printSummary } from "./printSummary.ts";
 
 export const interactiveRendererFactory: RendererFactory = {
 	about: {

packages/cli/src/renderers/interactive/printFile.ts

@@ -1,7 +1,7 @@
-import { FileReport } from "@flint.fyi/core";
+import type { FileReport } from "@flint.fyi/core";
 import * as fs from "node:fs";
 
-import { Presenter } from "../../presenters/types.js";
+import type { Presenter } from "../../presenters/types.ts";
 
 export async function printFile(
 	filePath: string,

packages/cli/src/renderers/interactive/printSummary.ts

@@ -1,7 +1,7 @@
-import { FileResults, hasFix } from "@flint.fyi/core";
+import { type FileResults, hasFix } from "@flint.fyi/core";
 import { styleText } from "node:util";
 
-import { pluralize } from "../../presenters/pluralize.js";
+import { pluralize } from "../../presenters/pluralize.ts";
 
 export function printSummary(filesWithReportResults: [string, FileResults][]) {
 	const counts = {

packages/cli/src/renderers/singleRendererFactory.ts

@@ -1,6 +1,6 @@
 import * as fs from "node:fs/promises";
 
-import { RendererFactory } from "./types.js";
+import type { RendererFactory } from "./types.ts";
 
 export const singleRendererFactory: RendererFactory = {
 	about: {

packages/cli/src/renderers/types.ts

@@ -1,6 +1,6 @@
-import { FormattingResults, LintResults } from "@flint.fyi/core";
+import type { FormattingResults, LintResults } from "@flint.fyi/core";
 
-import { Presenter } from "../presenters/types.js";
+import type { Presenter } from "../presenters/types.ts";
 
 export interface Renderer {
 	announce(): void;

packages/cli/src/runCli.ts

@@ -1,11 +1,11 @@
 import { parseArgs } from "node:util";
 
 import packageData from "../package.json" with { type: "json" };
-import { findConfigFileName } from "./findConfigFileName.js";
-import { options } from "./options.js";
-import { createRendererFactory } from "./renderers/createRendererFactory.js";
-import { runCliOnce } from "./runCliOnce.js";
-import { runCliWatch } from "./runCliWatch.js";
+import { findConfigFileName } from "./findConfigFileName.ts";
+import { options } from "./options.ts";
+import { createRendererFactory } from "./renderers/createRendererFactory.ts";
+import { runCliOnce } from "./runCliOnce.ts";
+import { runCliWatch } from "./runCliWatch.ts";
 
 export async function runCli(args: string[]) {
 	const { values } = parseArgs({

packages/cli/src/runCliOnce.ts

@@ -3,9 +3,9 @@ import { debugForFile } from "debug-for-file";
 import path from "node:path";
 import { pathToFileURL } from "node:url";
 
-import { runPrettier } from "./formatting/runPrettier.js";
-import { OptionsValues } from "./options.js";
-import { Renderer } from "./renderers/types.js";
+import { runPrettier } from "./formatting/runPrettier.ts";
+import type { OptionsValues } from "./options.ts";
+import type { Renderer } from "./renderers/types.ts";
 
 const log = debugForFile(import.meta.filename);
 

packages/cli/src/runCliWatch.ts

@@ -2,9 +2,9 @@ import debounce from "debounce";
 import { debugForFile } from "debug-for-file";
 import * as fs from "node:fs";
 
-import { OptionsValues } from "./options.js";
-import { Renderer } from "./renderers/types.js";
-import { runCliOnce } from "./runCliOnce.js";
+import type { OptionsValues } from "./options.ts";
+import type { Renderer } from "./renderers/types.ts";
+import { runCliOnce } from "./runCliOnce.ts";
 
 const log = debugForFile(import.meta.filename);
 

packages/core/src/cache/readFromCache.ts

@@ -1,10 +1,10 @@
 import { CachedFactory } from "cached-factory";
 import { debugForFile } from "debug-for-file";
 
-import { readFileSafeAsJson } from "../running/readFileSafeAsJson.js";
-import { CacheStorage } from "../types/cache.js";
-import { cacheFilePath } from "./constants.js";
-import { getFileTouchTime } from "./getFileTouchTime.js";
+import { readFileSafeAsJson } from "../running/readFileSafeAsJson.ts";
+import type { CacheStorage } from "../types/cache.ts";
+import { cacheFilePath } from "./constants.ts";
+import { getFileTouchTime } from "./getFileTouchTime.ts";
 
 const log = debugForFile(import.meta.filename);