feat(prerender): support quoted true / false values and 0 / 1 (#6772)

.changeset/cuddly-eels-melt.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Allow `import.meta.env` values of `0`, `1`, `true`, and `false` to be used for `export const prerender` statements

packages/astro/src/vite-plugin-scanner/scan.ts

@@ -13,6 +13,25 @@ function includesExport(code: string) {
 	return false;
 }
 
+// Support quoted values to allow statically known `import.meta.env` variables to be used
+function isQuoted(value: string) {
+	return (value[0] === '"' || value[0] === "'") && value[value.length - 1] === value[0]
+}
+
+function isTruthy(value: string) {
+	if (isQuoted(value)) {
+		value = value.slice(1, -1);
+	}
+	return value === 'true' || value === '1';
+}
+
+function isFalsy(value: string) {
+	if (isQuoted(value)) {
+		value = value.slice(1, -1);
+	}
+	return value === 'false' || value === '0';
+}
+
 let didInit = false;
 
 export async function scan(code: string, id: string): Promise<PageOptions> {
@@ -39,14 +58,14 @@ export async function scan(code: string, id: string): Promise<PageOptions> {
 			// For a given export, check the value of the first non-whitespace token.
 			// Basically extract the `true` from the statement `export const prerender = true`
 			const suffix = code.slice(endOfLocalName).trim().replace(/\=/, '').trim().split(/[;\n]/)[0];
-			if (prefix !== 'const' || !(suffix === 'true' || suffix === 'false')) {
+			if (prefix !== 'const' || !(isTruthy(suffix) || isFalsy(suffix))) {
 				throw new AstroError({
 					...AstroErrorData.InvalidPrerenderExport,
 					message: AstroErrorData.InvalidPrerenderExport.message(prefix, suffix),
 					location: { file: id },
 				});
 			} else {
-				pageOptions[name as keyof PageOptions] = suffix === 'true';
+				pageOptions[name as keyof PageOptions] = isTruthy(suffix);
 			}
 		}
 	}

packages/astro/test/units/vite-plugin-scanner/scan.test.js

@@ -17,6 +17,36 @@ describe('astro scan', () => {
 		expect(result.prerender).to.equal(false);
 	});
 
+	it('recognizes single quoted boolean (\'true\')', async () => {
+		const result = await scan(`export const prerender = 'true';`, '/src/components/index.astro');
+		expect(result.prerender).to.equal(true);
+	});
+
+	it('recognizes double quoted boolean ("true")', async () => {
+		const result = await scan(`export const prerender = "true";`, '/src/components/index.astro');
+		expect(result.prerender).to.equal(true);
+	});
+
+	it('recognizes double quoted boolean ("false")', async () => {
+		const result = await scan(`export const prerender = "false";`, '/src/components/index.astro');
+		expect(result.prerender).to.equal(false);
+	});
+
+	it('recognizes single quoted boolean (\'false\')', async () => {
+		const result = await scan(`export const prerender = 'false';`, '/src/components/index.astro');
+		expect(result.prerender).to.equal(false);
+	});
+
+	it('recognizes number (1)', async () => {
+		const result = await scan(`export const prerender = 1;`, '/src/components/index.astro');
+		expect(result.prerender).to.equal(true);
+	});
+
+	it('recognizes number (0)', async () => {
+		const result = await scan(`export const prerender = 0;`, '/src/components/index.astro');
+		expect(result.prerender).to.equal(false);
+	});
+
 	it('throws on let boolean literal', async () => {
 		try {
 			const result = await scan(`export let prerender = true;`, '/src/components/index.astro');