fix(types): improve type safety (#516)

Author: danielroe

src/build.ts

@@ -100,7 +100,7 @@ async function _build(
     pkg.unbuild || pkg.build,
     inputConfig,
     preset,
-    <BuildOptions>{
+    {
       name: (pkg?.name || "").split("/").pop() || "default",
       rootDir,
       entries: [],
@@ -171,7 +171,7 @@ async function _build(
         },
       },
       parallel: false,
-    },
+    } satisfies BuildOptions,
   ) as BuildOptions;
 
   // Resolve dirs relative to rootDir
@@ -265,8 +265,8 @@ async function _build(
     for (const dir of new Set(
       options.entries
         .map((e) => e.outDir)
-        .filter(Boolean)
-        .sort() as unknown as Set<string>,
+        .filter((p): p is NonNullable<typeof p> => !!p)
+        .sort(),
     )) {
       if (
         dir === options.rootDir ||

src/builders/rollup/build.ts

@@ -84,13 +84,13 @@ export async function rollupBuild(ctx: BuildContext): Promise<void> {
       removeShebangPlugin(),
       ctx.options.rollup.emitCJS && fixCJSExportTypePlugin(ctx),
     ].filter(
-      (plugin) =>
+      (plugin): plugin is NonNullable<Exclude<typeof plugin, false>> =>
         /**
          * Issue: #396
          * rollup-plugin-dts conflicts with rollup-plugin-commonjs:
          * https://github.com/Swatinem/rollup-plugin-dts?tab=readme-ov-file#what-to-expect
          */
-        plugin && (!("name" in plugin) || plugin.name !== "commonjs"),
+        !!plugin && (!("name" in plugin) || plugin.name !== "commonjs"),
     );
 
     await ctx.hooks.callHook("rollup:dts:options", ctx, rollupOptions);

src/builders/rollup/config.ts

@@ -17,7 +17,7 @@ import { DEFAULT_EXTENSIONS, getChunkFilename, resolveAliases } from "./utils";
 
 export function getRollupOptions(ctx: BuildContext): RollupOptions {
   const _aliases = resolveAliases(ctx);
-  return (<RollupOptions>{
+  return {
     input: Object.fromEntries(
       ctx.options.entries
         .filter((entry) => entry.builder === "rollup")
@@ -29,7 +29,7 @@ export function getRollupOptions(ctx: BuildContext): RollupOptions {
 
     output: [
       ctx.options.rollup.emitCJS &&
-        <OutputOptions>{
+        ({
           dir: resolve(ctx.options.rootDir, ctx.options.outDir),
           entryFileNames: "[name].cjs",
           chunkFileNames: (chunk: PreRenderedChunk) =>
@@ -42,8 +42,8 @@ export function getRollupOptions(ctx: BuildContext): RollupOptions {
           freeze: false,
           sourcemap: ctx.options.sourcemap,
           ...ctx.options.rollup.output,
-        },
-      <OutputOptions>{
+        } satisfies OutputOptions),
+      {
         dir: resolve(ctx.options.rootDir, ctx.options.outDir),
         entryFileNames: "[name].mjs",
         chunkFileNames: (chunk: PreRenderedChunk) =>
@@ -55,10 +55,10 @@ export function getRollupOptions(ctx: BuildContext): RollupOptions {
         freeze: false,
         sourcemap: ctx.options.sourcemap,
         ...ctx.options.rollup.output,
-      },
-    ].filter(Boolean),
+      } satisfies OutputOptions,
+    ].filter(Boolean) as OutputOptions[],
 
-    external(originalId) {
+    external(originalId): boolean {
       // Resolve aliases
       const resolvedId = resolveAlias(originalId, _aliases);
 
@@ -105,7 +105,7 @@ export function getRollupOptions(ctx: BuildContext): RollupOptions {
       return false;
     },
 
-    onwarn(warning, rollupWarn) {
+    onwarn(warning, rollupWarn): void {
       if (!warning.code || !["CIRCULAR_DEPENDENCY"].includes(warning.code)) {
         rollupWarn(warning);
       }
@@ -154,6 +154,7 @@ export function getRollupOptions(ctx: BuildContext): RollupOptions {
         }),
 
       ctx.options.rollup.preserveDynamicImports && {
+        name: "unbuild=preserve-dynamic-imports",
         renderDynamicImport(): { left: string; right: string } {
           return { left: "import(", right: ")" };
         },
@@ -162,6 +163,6 @@ export function getRollupOptions(ctx: BuildContext): RollupOptions {
       ctx.options.rollup.cjsBridge && cjsPlugin({}),
 
       rawPlugin(),
-    ].filter(Boolean),
-  }) as RollupOptions;
+    ].filter((p): p is NonNullable<Exclude<typeof p, false>> => !!p),
+  } satisfies RollupOptions;
 }

src/builders/rollup/plugins/cjs.ts

@@ -32,7 +32,7 @@ export function fixCJSExportTypePlugin(ctx: BuildContext): Plugin {
         info.isEntry
       );
     },
-  }) as Plugin;
+  });
 }
 
 const CJSyntaxRe = /__filename|__dirname|require\(|require\.resolve\(/;

src/builders/rollup/plugins/json.ts

@@ -1,15 +1,15 @@
-import type { Plugin, TransformHook } from "rollup";
+import type { Plugin, TransformHook, TransformResult } from "rollup";
 import type { RollupJsonOptions } from "@rollup/plugin-json";
 import rollupJSONPlugin from "@rollup/plugin-json";
 
 const EXPORT_DEFAULT = "export default ";
 
 export function JSONPlugin(options: RollupJsonOptions): Plugin {
   const plugin = rollupJSONPlugin(options);
-  return <Plugin>{
+  return {
     ...plugin,
     name: "unbuild-json",
-    transform(code, id) {
+    transform(code, id): TransformResult {
       const res = (plugin.transform as TransformHook)!.call(this, code, id);
       if (
         res &&
@@ -22,5 +22,5 @@ export function JSONPlugin(options: RollupJsonOptions): Plugin {
       }
       return res;
     },
-  };
+  } satisfies Plugin;
 }

src/builders/rollup/types.ts

@@ -3,6 +3,7 @@ import type {
   RollupBuild,
   OutputOptions,
   InputPluginOption,
+  Plugin,
 } from "rollup";
 import type { RollupReplaceOptions } from "@rollup/plugin-replace";
 import type { RollupAliasOptions } from "@rollup/plugin-alias";
@@ -107,7 +108,7 @@ export interface RollupBuildOptions {
 }
 
 export interface RollupOptions extends _RollupOptions {
-  plugins: InputPluginOption[];
+  plugins: Plugin[];
 }
 
 export interface RollupHooks {

src/types.ts

@@ -98,7 +98,7 @@ export interface BuildOptions {
   /**
    * Watch mode options.
    */
-  watchOptions: WatcherOptions;
+  watchOptions: WatcherOptions | undefined;
 
   /**
    * Stub options, where [jiti](https://github.com/unjs/jiti)