[feat] do uppercase http verbs migration on the fly (#6371)

Small QoL improvement for anyone who is behind a few versions and didn't do that migration yet.

Author: dummdidumm

.changeset/chilled-clouds-move.md

@@ -0,0 +1,5 @@
+---
+'svelte-migrate': patch
+---
+
+[feat] do uppercase http verbs migration on the fly

packages/migrate/migrations/routes/migrate_page_server/index.js

@@ -10,7 +10,8 @@ import {
 	parse,
 	rewrite_returns,
 	rewrite_type,
-	unwrap
+	unwrap,
+	uppercase_migration
 } from '../utils.js';
 import * as TASKS from '../tasks.js';
 
@@ -19,6 +20,7 @@ const give_up = `${error('Update +page.server.js', TASKS.PAGE_ENDPOINT)}\n\n`;
 /**
  * @param {string} content
  * @param {string} filename
+ * @returns {string}
  */
 export function migrate_page_server(content, filename) {
 	const file = parse(content);
@@ -28,6 +30,14 @@ export function migrate_page_server(content, filename) {
 		file.exports.map.has(name)
 	);
 
+	// If user didn't do the uppercase verbs migration yet, do it here on the fly.
+	const uppercased = uppercase_migration(methods, file);
+	if (!uppercased) {
+		return give_up + content;
+	} else if (uppercased !== content) {
+		return migrate_page_server(uppercased, filename);
+	}
+
 	const non_get_methods = methods.filter((name) => name !== 'GET');
 
 	const unmigrated = new Set(methods);

packages/migrate/migrations/routes/migrate_page_server/samples.md

@@ -153,3 +153,25 @@ export function load() {
 	return ;
 }
 ```
+
+## A get function that only returns body
+
+```js before
+/** @type {import('./$types').RequestHandler} */
+export function get() {
+	return {
+		body: {
+			a: 1
+		}
+	};
+}
+```
+
+```js after
+/** @type {import('./$types').PageServerLoad} */
+export function load() {
+	return {
+		a: 1
+	};
+}
+```

packages/migrate/migrations/routes/migrate_server/index.js

@@ -2,6 +2,7 @@ import ts from 'typescript';
 import {
 	automigration,
 	dedent,
+	uppercase_migration,
 	error,
 	get_function_node,
 	get_object_nodes,
@@ -18,7 +19,10 @@ import * as TASKS from '../tasks.js';
 
 const give_up = `${error('Update +server.js', TASKS.STANDALONE_ENDPOINT)}\n\n`;
 
-/** @param {string} content */
+/**
+ * @param {string} content
+ * @returns {string}
+ */
 export function migrate_server(content) {
 	const file = parse(content);
 	if (!file) return give_up + content;
@@ -29,6 +33,14 @@ export function migrate_server(content) {
 		file.exports.map.has(name)
 	);
 
+	// If user didn't do the uppercase verbs migration yet, do it here on the fly.
+	const uppercased = uppercase_migration(methods, file);
+	if (!uppercased) {
+		return give_up + content;
+	} else if (uppercased !== content) {
+		return migrate_server(uppercased);
+	}
+
 	const unmigrated = new Set(methods);
 
 	/** @type {Map<string, string>} */

packages/migrate/migrations/routes/migrate_server/samples.md

@@ -188,3 +188,25 @@ export function GET() {
 	return;
 }
 ```
+
+## A GET function that returns a JSON object
+
+```js before
+export function get() {
+	return {
+		body: {
+			a: 1
+		}
+	};
+}
+```
+
+```js after
+import { json } from '@sveltejs/kit';
+
+export function GET() {
+	return json({
+		a: 1
+	});
+}
+```

packages/migrate/migrations/routes/utils.js

@@ -494,3 +494,38 @@ export function rewrite_type(node, code, old_type, new_type) {
 		code.overwrite(start, start + old_type.length, new_type);
 	}
 }
+
+/**
+ * Does the HTTP verbs uppercase migration if it didn't happen yet. If a string
+ * is returned, the migration was done or wasn't needed. If undefined is returned,
+ * the migration is needed but couldn't be done.
+ *
+ * @param {string[]} methods
+ * @param {NonNullable<ReturnType<typeof parse>>} file
+ */
+export function uppercase_migration(methods, file) {
+	const old_methods = ['get', 'post', 'put', 'patch', 'del'].filter((name) =>
+		file.exports.map.has(name)
+	);
+
+	if (old_methods.length && !methods.length) {
+		for (const statement of file.ast.statements) {
+			for (const method of old_methods) {
+				const fn = get_function_node(
+					statement,
+					/** @type{string} */ (file.exports.map.get(method))
+				);
+				if (!fn?.name) {
+					return;
+				}
+				file.code.overwrite(
+					fn.name.getStart(),
+					fn.name.getEnd(),
+					method === 'del' ? 'DELETE' : method.toUpperCase()
+				);
+			}
+		}
+	}
+
+	return file.code.toString();
+}