fix: emit transpilation warnings after cache-hit

Author: privatenumber

src/transform/apply-transformers.ts

@@ -15,6 +15,7 @@ type IntersectionArray<T extends unknown[]> = (
 type TransformerResult = {
 	code: string;
 	map: SourceMap;
+	warnings?: any[];
 } | undefined;
 
 type Transformer<
@@ -39,6 +40,7 @@ type AddSourceMap<T> = Omit<T, 'map'> & { map: RawSourceMap };
 export type Transformed = {
 	code: string;
 	map: RawSourceMap;
+	warnings: any[];
 };
 
 export function applyTransformersSync<
@@ -49,6 +51,7 @@ export function applyTransformersSync<
 	transformers: T,
 ) {
 	const maps: SourceMap[] = [];
+	const warnings = [];
 	const result = { code };
 
 	for (const transformer of transformers) {
@@ -57,12 +60,17 @@ export function applyTransformersSync<
 		if (transformed) {
 			Object.assign(result, transformed);
 			maps.unshift(transformed.map);
+
+			if (transformed.warnings) {
+				warnings.push(...transformed.warnings);
+			}
 		}
 	}
 
 	return {
 		...result,
 		map: remapping(maps as SourceMapInput[], () => null),
+		warnings,
 	} as unknown as AddSourceMap<IntersectionArray<Results<[...T]>>>;
 }
 
@@ -74,6 +82,7 @@ export async function applyTransformers<
 	transformers: T,
 ) {
 	const maps: SourceMap[] = [];
+	const warnings = [];
 	const result = { code };
 
 	for (const transformer of transformers) {
@@ -82,11 +91,16 @@ export async function applyTransformers<
 		if (transformed) {
 			Object.assign(result, transformed);
 			maps.unshift(transformed.map);
+
+			if (transformed.warnings) {
+				warnings.push(...transformed.warnings);
+			}
 		}
 	}
 
 	return {
 		...result,
 		map: remapping(maps as SourceMapInput[], () => null),
+		warnings,
 	} as unknown as AddSourceMap<IntersectionArray<Results<[...T]>>>;
 }

src/transform/index.ts

@@ -37,28 +37,28 @@ export function transformSync(
 	});
 
 	const hash = sha1(code + JSON.stringify(esbuildOptions) + esbuildVersion);
-	const cacheHit = cache.get(hash);
+	let transformed = cache.get(hash);
 
-	if (cacheHit) {
-		return cacheHit;
-	}
-
-	const transformed = applyTransformersSync(
-		filePath,
-		code,
-		[
-			// eslint-disable-next-line @typescript-eslint/no-shadow
-			(filePath, code) => {
+	if (!transformed) {
+		transformed = applyTransformersSync(
+			filePath,
+			code,
+			[
 				// eslint-disable-next-line @typescript-eslint/no-shadow
-				const transformed = esbuildTransformSync(code, esbuildOptions);
-				if (esbuildOptions.sourcefile !== filePath) {
-					transformed.map = transformed.map.replace(`"${esbuildOptions.sourcefile}"`, `"${filePath}"`);
-				}
-				return transformed;
-			},
-			transformDynamicImport,
-		] as const,
-	);
+				(filePath, code) => {
+					// eslint-disable-next-line @typescript-eslint/no-shadow
+					const transformed = esbuildTransformSync(code, esbuildOptions);
+					if (esbuildOptions.sourcefile !== filePath) {
+						transformed.map = transformed.map.replace(`"${esbuildOptions.sourcefile}"`, `"${filePath}"`);
+					}
+					return transformed;
+				},
+				transformDynamicImport,
+			] as const,
+		);
+
+		cache.set(hash, transformed);
+	}
 
 	if (transformed.warnings.length > 0) {
 		const { warnings } = transformed;
@@ -67,8 +67,6 @@ export function transformSync(
 		}
 	}
 
-	cache.set(hash, transformed);
-
 	return transformed;
 }
 
@@ -85,27 +83,28 @@ export async function transform(
 	});
 
 	const hash = sha1(code + JSON.stringify(esbuildOptions) + esbuildVersion);
-	const cacheHit = cache.get(hash);
-	if (cacheHit) {
-		return cacheHit;
-	}
+	let transformed = cache.get(hash);
 
-	const transformed = await applyTransformers(
-		filePath,
-		code,
-		[
-			// eslint-disable-next-line @typescript-eslint/no-shadow
-			async (filePath, code) => {
+	if (!transformed) {
+		transformed = await applyTransformers(
+			filePath,
+			code,
+			[
 				// eslint-disable-next-line @typescript-eslint/no-shadow
-				const transformed = await esbuildTransform(code, esbuildOptions);
-				if (esbuildOptions.sourcefile !== filePath) {
-					transformed.map = transformed.map.replace(`"${esbuildOptions.sourcefile}"`, `"${filePath}"`);
-				}
-				return transformed;
-			},
-			transformDynamicImport,
-		] as const,
-	);
+				async (filePath, code) => {
+					// eslint-disable-next-line @typescript-eslint/no-shadow
+					const transformed = await esbuildTransform(code, esbuildOptions);
+					if (esbuildOptions.sourcefile !== filePath) {
+						transformed.map = transformed.map.replace(`"${esbuildOptions.sourcefile}"`, `"${filePath}"`);
+					}
+					return transformed;
+				},
+				transformDynamicImport,
+			] as const,
+		);
+
+		cache.set(hash, transformed);
+	}
 
 	if (transformed.warnings.length > 0) {
 		const { warnings } = transformed;
@@ -114,7 +113,5 @@ export async function transform(
 		}
 	}
 
-	cache.set(hash, transformed);
-
 	return transformed;
 }