feat: generate correct declarations, diagnostics, and .tsbuildinfo wh…

…en a Rollup cache is being used. Fixes #140

src/plugin/typescript-plugin.ts

@@ -1,4 +1,4 @@
-import {ExistingRawSourceMap, InputOptions, OutputBundle, OutputOptions, Plugin, PluginContext, RenderedChunk, SourceDescription} from "rollup";
+import {ExistingRawSourceMap, InputOptions, OutputBundle, OutputOptions, Plugin, PluginContext, RenderedChunk, RollupCache, SourceDescription} from "rollup";
 import {getParsedCommandLine} from "../util/get-parsed-command-line/get-parsed-command-line";
 import {getForcedCompilerOptions} from "../util/get-forced-compiler-options/get-forced-compiler-options";
 import {getSourceDescriptionFromEmitOutput} from "../util/get-source-description-from-emit-output/get-source-description-from-emit-output";
@@ -29,6 +29,7 @@ import path from "crosspath";
 import {loadBabel, loadSwc} from "../util/transpiler-loader";
 import {BabelConfigFactory, getBabelConfig, getDefaultBabelOptions, getForcedBabelOptions, replaceBabelHelpers} from "../transpiler/babel";
 import {getSwcConfigFactory, SwcConfigFactory} from "../transpiler/swc";
+import {inputOptionsAreEqual} from "../util/rollup/rollup-util";
 
 /**
  * The name of the Rollup plugin
@@ -97,6 +98,11 @@ export default function typescriptRollupPlugin(pluginInputOptions: Partial<Types
 	 */
 	let rollupInputOptions: InputOptions;
 
+	/**
+	 * The previously emitted Rollup cache used as input, if any
+	 */
+	let inputCache: RollupCache | undefined;
+
 	/**
 	 * A Set of the entry filenames for when using rollup-plugin-multi-entry (we need to track this for generating valid declarations)
 	 */
@@ -107,7 +113,7 @@ export default function typescriptRollupPlugin(pluginInputOptions: Partial<Types
 	 */
 	let MULTI_ENTRY_MODULE: string | undefined;
 
-	const addAndEmitFile = (fileName: string, text: string, dependencyCb: (dependency: string) => void): SourceDescription | undefined => {
+	const addFile = (fileName: string, text: string, dependencyCb: (dependency: string) => void): void => {
 		// Add the file to the CompilerHost
 		host.add({fileName, text, fromRollup: true});
 
@@ -121,6 +127,10 @@ export default function typescriptRollupPlugin(pluginInputOptions: Partial<Types
 				dependencyCb(pickedDependency);
 			}
 		}
+	};
+
+	const addAndEmitFile = (fileName: string, text: string, dependencyCb: (dependency: string) => void): SourceDescription | undefined => {
+		addFile(fileName, text, dependencyCb);
 
 		// Get some EmitOutput, optionally from the cache if the file contents are unchanged
 		const emitOutput = host.emit(fileName, false);
@@ -136,10 +146,13 @@ export default function typescriptRollupPlugin(pluginInputOptions: Partial<Types
 		 * Invoked when Input options has been received by Rollup
 		 */
 		async options(options: InputOptions): Promise<undefined> {
-			// Break if the options aren't different from the previous ones
-			if (rollupInputOptions != null) return;
+			// Always update the input cache
+			inputCache = typeof options.cache === "boolean" ? undefined : options.cache;
+
+			// Don't proceed if the options are identical to the previous ones
+			if (rollupInputOptions != null && inputOptionsAreEqual(rollupInputOptions, options)) return;
 
-			// Re-assign the input options
+			// Re-assign the full input options
 			rollupInputOptions = options;
 
 			const multiEntryPlugin = options.plugins?.find(plugin => plugin != null && typeof plugin !== "boolean" && plugin.name === "multi-entry");
@@ -462,6 +475,23 @@ export default function typescriptRollupPlugin(pluginInputOptions: Partial<Types
 		 * from the LanguageService
 		 */
 		generateBundle(this: PluginContext, outputOptions: OutputOptions, bundle: OutputBundle): void {
+			// If a cache was provided to Rollup,
+			// some or all files may not have been added to the CompilerHost
+			// and therefore it will not be possible to compile correct diagnostics,
+			// declarations, and/or .buildinfo. To work around this, we'll have to make sure
+			// all files that are part of the compilation unit is in fact added to the CompilerHost
+			if (inputCache != null) {
+				for (const module of inputCache.modules) {
+					const normalizedFile = path.normalize(module.id);
+
+					// Don't proceed if we already know about that file
+					if (host.has(normalizedFile)) continue;
+
+					// Add to the CompilerHost
+					addFile(normalizedFile, module.originalCode, dependency => this.addWatchFile(dependency));
+				}
+			}
+
 			// If debugging is active, log the outputted files
 			for (const file of Object.values(bundle)) {
 				if (!("fileName" in file)) continue;

src/util/rollup/rollup-util.ts

@@ -0,0 +1,49 @@
+import {InputOptions} from "rollup";
+
+interface EqualResult {
+	equal: true;
+}
+
+interface NotEqualResult {
+	equal: false;
+	path: string[];
+}
+
+type EqualityResult = EqualResult | NotEqualResult;
+
+const ignoredKeys = new Set(["cache"]);
+
+/**
+ * Treat the options as equal if their properties are somewhat equal, not taking their cache into account
+ */
+export function inputOptionsAreEqual(a: InputOptions, b: InputOptions): boolean {
+	return inputValuesAreEqual(a, b).equal;
+}
+
+function inputValuesAreEqual(a: unknown, b: unknown, path: string[] = []): EqualityResult {
+	if (a === b || (a == null && b == null)) return {equal: true};
+	else if (typeof a !== typeof b) return {equal: false, path};
+	else if (Array.isArray(a)) {
+		if (!Array.isArray(b)) return {equal: false, path};
+		else if (a.length !== b.length) return {equal: false, path};
+		else if (a.some((element, index) => !inputValuesAreEqual(element, b[index], [...path, String(index)]).equal)) {
+			return {equal: false, path};
+		} else {
+			return {equal: true};
+		}
+	} else if (typeof a === "object" && a != null) {
+		if (typeof b !== "object" || b == null) return {equal: false, path};
+
+		const aKeys = Object.keys(a).filter(key => !ignoredKeys.has(key));
+		const bKeys = Object.keys(b).filter(key => !ignoredKeys.has(key));
+
+		if (aKeys.length !== bKeys.length) return {equal: false, path};
+		else if (aKeys.some(key => !inputValuesAreEqual(a[key as keyof typeof a], b[key as keyof typeof b], [...path, key]).equal)) {
+			return {equal: false, path};
+		} else {
+			return {equal: true};
+		}
+	} else {
+		return {equal: true};
+	}
+}

test/cache.test.ts

@@ -0,0 +1,30 @@
+import test from "ava";
+import {withTypeScript} from "./util/ts-macro";
+import {formatCode} from "./util/format-code";
+import {generateRollupBundle} from "./setup/setup-rollup";
+
+test.serial("Declaration bundling works properly when Rollup is using a cache. #1", withTypeScript, async (t, {typescript}) => {
+	const bundle = await generateRollupBundle(
+		[
+			{
+				entry: true,
+				fileName: "index.ts",
+				text: `\
+				export default () => 42
+				`
+			}
+		],
+		{typescript, runCachedBuild: true, debug: false}
+	);
+	const {
+		declarations: [file]
+	} = bundle;
+
+	t.deepEqual(
+		formatCode(file.code),
+		formatCode(`\
+		declare const _default: () => number;
+		export { _default as default };
+		`)
+	);
+});

test/setup/setup-rollup.ts

@@ -1,4 +1,4 @@
-import {Plugin, rollup, RollupOptions, RollupOutput} from "rollup";
+import {Plugin, rollup, RollupBuild, RollupCache, RollupOptions, RollupOutput} from "rollup";
 import commonjs from "@rollup/plugin-commonjs";
 import typescriptRollupPlugin from "../../src/plugin/typescript-plugin";
 import {HookRecord, InputCompilerOptions, TypescriptPluginBabelOptions, TypescriptPluginOptions, TypescriptPluginSwcOptions} from "../../src/plugin/typescript-plugin-options";
@@ -42,6 +42,7 @@ export interface GenerateRollupBundleOptions {
 	browserslist: TypescriptPluginOptions["browserslist"];
 	chunkFileNames: string;
 	entryFileNames: string;
+	runCachedBuild: boolean;
 }
 
 /**
@@ -52,6 +53,7 @@ export async function generateRollupBundle(
 	{
 		rollupOptions = {},
 		format = "esm",
+		runCachedBuild = false,
 		prePlugins = [],
 		postPlugins = [],
 		entryFileNames,
@@ -141,37 +143,51 @@ export async function generateRollupBundle(
 		}
 	}
 
-	const result = await rollup({
-		input,
-		...rollupOptions,
-		onwarn: (warning, defaultHandler) => {
-			// Eat all irrelevant Rollup warnings (such as 'Generated an empty chunk: "index") while running tests
-			if (!warning.message.includes("Generated an empty chunk") && !warning.message.includes(`Circular dependency:`) && !warning.message.includes(`Conflicting namespaces:`)) {
-				defaultHandler(warning);
-			}
-		},
-		plugins: [
-			{
-				name: "VirtualFileResolver",
-				resolveId,
-				load
+	let cache: RollupCache | undefined;
+	let result: RollupBuild | undefined;
+
+	while (true) {
+		result = await rollup({
+			input,
+			cache,
+			...rollupOptions,
+			onwarn: (warning, defaultHandler) => {
+				// Eat all irrelevant Rollup warnings (such as 'Generated an empty chunk: "index") while running tests
+				if (!warning.message.includes("Generated an empty chunk") && !warning.message.includes(`Circular dependency:`) && !warning.message.includes(`Conflicting namespaces:`)) {
+					defaultHandler(warning);
+				}
 			},
-			commonjs(),
-			...prePlugins,
-			typescriptRollupPlugin({
-				...context,
-				fileSystem,
-				transformers,
-				browserslist,
-				babelConfig,
-				swcConfig
-			}),
-			...(rollupOptions.plugins == null ? [] : rollupOptions.plugins),
-			...postPlugins
-		]
-	});
+			plugins: [
+				{
+					name: "VirtualFileResolver",
+					resolveId,
+					load
+				},
+				commonjs(),
+				...prePlugins,
+				typescriptRollupPlugin({
+					...context,
+					fileSystem,
+					transformers,
+					browserslist,
+					babelConfig,
+					swcConfig
+				}),
+				...(rollupOptions.plugins == null ? [] : rollupOptions.plugins),
+				...postPlugins
+			]
+		});
+
+		if (runCachedBuild && cache == null) {
+			cache = result.cache;
+
+			// Run again, this time with caching
+			continue;
+		} else {
+			break;
+		}
+	}
 
-	const extraFiles: {type: "chunk" | "asset"; source: string; fileName: string}[] = [];
 	const bundle = await result.generate({
 		dir: context.dist,
 		format,
@@ -180,7 +196,7 @@ export async function generateRollupBundle(
 		...(chunkFileNames == null ? {} : {chunkFileNames})
 	});
 
-	for (const file of [...bundle.output, ...extraFiles]) {
+	for (const file of bundle.output) {
 		if (file.type === "chunk" && "code" in file) {
 			js.push({
 				code: file.code,