remove enableSourcemap option

Author: dummdidumm

packages/svelte/src/compiler/types/index.d.ts

@@ -178,10 +178,6 @@ export interface CompileOptions extends ModuleCompileOptions {
 	 * @default null
 	 */
 	cssOutputFilename?: string;
-
-	// Other Svelte 4 compiler options:
-	// enableSourcemap?: EnableSourcemap; // TODO bring back? https://github.com/sveltejs/svelte/pull/6835
-	// legacy?: boolean; // TODO compiler error noting the new purpose?
 }
 
 export interface ModuleCompileOptions {

packages/svelte/src/compiler/validate-options.js

@@ -87,7 +87,6 @@ export const validate_component_options =
 
 			namespace: list(['html', 'svg', 'foreign']),
 
-			// TODO this is a sourcemap option, would be good to put under a sourcemap namespace
 			outputFilename: string(undefined),
 
 			preserveComments: boolean(false),
@@ -96,16 +95,15 @@ export const validate_component_options =
 
 			runes: boolean(undefined),
 
-			sourcemap: validator(undefined, (input, keypath) => {
-				// TODO
-				return input;
-			}),
-
-			enableSourcemap: validator(undefined, (input, keypath) => {
-				// TODO decide if we want to keep this
+			sourcemap: validator(undefined, (input) => {
+				// Source maps can take on a variety of values, including string, JSON, map objects from magic-string and source-map,
+				// so there's no good way to check type validity here
 				return input;
 			}),
 
+			enableSourcemap: warn_removed(
+				'The enableSourcemap option has been removed. Source maps are always generated now, and tooling can choose to ignore them.'
+			),
 			hydratable: warn_removed(
 				'The hydratable option has been removed. Svelte components are always hydratable now.'
 			),

packages/svelte/tests/sourcemaps/samples/no-sourcemap/_config.js

@@ -672,10 +672,6 @@ declare module 'svelte/compiler' {
 		 * @default null
 		 */
 		cssOutputFilename?: string;
-
-		// Other Svelte 4 compiler options:
-		// enableSourcemap?: EnableSourcemap; // TODO bring back? https://github.com/sveltejs/svelte/pull/6835
-		// legacy?: boolean; // TODO compiler error noting the new purpose?
 	}
 
 	interface ModuleCompileOptions {
@@ -754,8 +750,11 @@ declare module 'svelte/compiler' {
 		legacy_dependencies: Binding[];
 		/** Legacy props: the `class` in `{ export klass as class}` */
 		prop_alias: string | null;
-		/** If this is set, all references should use this expression instead of the identifier name */
-		expression: Expression | null;
+		/**
+		 * If this is set, all references should use this expression instead of the identifier name.
+		 * If a function is given, it will be called with the identifier at that location and should return the new expression.
+		 */
+		expression: Expression | ((id: Identifier) => Expression) | null;
 		/** If this is set, all mutations should use this expression */
 		mutation: ((assignment: AssignmentExpression, context: Context<any, any>) => Expression) | null;
 	}
@@ -1407,7 +1406,7 @@ declare module 'svelte/compiler' {
 			/** Set if something in the array expression is shadowed within the each block */
 			array_name: Identifier | null;
 			index: Identifier;
-			item_name: string;
+			item: Identifier;
 			declarations: Map<string, Binding>;
 			/** List of bindings that are referenced within the expression */
 			references: Binding[];
@@ -2403,10 +2402,6 @@ declare module 'svelte/types/compiler/interfaces' {
 		 * @default null
 		 */
 		cssOutputFilename?: string;
-
-		// Other Svelte 4 compiler options:
-		// enableSourcemap?: EnableSourcemap; // TODO bring back? https://github.com/sveltejs/svelte/pull/6835
-		// legacy?: boolean; // TODO compiler error noting the new purpose?
 	}
 
 	interface ModuleCompileOptions {

packages/svelte/tests/sourcemaps/samples/no-sourcemap/input.svelte

@@ -61,6 +61,7 @@ Svelte now use Mutation Observers instead of IFrames to measure dimensions for `
 - The `false`/`true` (already deprecated previously) and the `"none"` values were removed as valid values from the `css` option
 - The `legacy` option was repurposed
 - The `hydratable` option has been removed. Svelte components are always hydratable now
+- The `enableSourcemap` option has been removed. Source maps are always generated now, tooling can choose to ignore it
 - The `tag` option was removed. Use `<svelte:options customElement="tag-name" />` inside the component instead
 - The `loopGuardTimeout`, `format`, `sveltePath`, `errorMode` and `varsReport` options were removed