[v3.0] Basic support for import assertions (#4646)

* Add acorn support for import assertions and extend AST

* Ignore pre-existing assertions on input files

* Naive support for JSON assertions in output

* Inject arbitrary import assertions

* Allows to disable import assertions altogether via `false`

* Support shorthand syntax for type assertions

* Keep assertions on fully dynamic imports

* Add documentation

* Add assertions to types

* Keep original assertions

* Make option a boolean

* Some extractions

* Allow plugins to add and change assertions

* Allow to pass assertions in this.resolve

* Warn for inconsistent import assertions

* Add new documentation

* Improve coverage

LICENSE.md

@@ -52,6 +52,13 @@ Repository: https://github.com/acornjs/acorn.git
 
 ---------------------------------------
 
+## acorn-import-assertions
+License: MIT
+By: Sven Sauleau
+Repository: https://github.com/xtuc/acorn-import-assertions
+
+---------------------------------------
+
 ## acorn-walk
 License: MIT
 By: Marijn Haverbeke, Ingvar Stepanyan, Adrian Heine

browser/LICENSE.md

@@ -52,6 +52,13 @@ Repository: https://github.com/acornjs/acorn.git
 
 ---------------------------------------
 
+## acorn-import-assertions
+License: MIT
+By: Sven Sauleau
+Repository: https://github.com/xtuc/acorn-import-assertions
+
+---------------------------------------
+
 ## acorn-walk
 License: MIT
 By: Marijn Haverbeke, Ingvar Stepanyan, Adrian Heine

browser/src/resolveId.ts

@@ -1,9 +1,5 @@
-import type {
-	CustomPluginOptions,
-	Plugin,
-	ResolvedId,
-	ResolveIdResult
-} from '../../src/rollup/types';
+import { ModuleLoaderResolveId } from '../../src/ModuleLoader';
+import type { CustomPluginOptions, Plugin, ResolveIdResult } from '../../src/rollup/types';
 import type { PluginDriver } from '../../src/utils/PluginDriver';
 import { resolveIdViaPlugins } from '../../src/utils/resolveIdViaPlugins';
 import { throwNoFileSystem } from './error';
@@ -13,16 +9,11 @@ export async function resolveId(
 	importer: string | undefined,
 	_preserveSymlinks: boolean,
 	pluginDriver: PluginDriver,
-	moduleLoaderResolveId: (
-		source: string,
-		importer: string | undefined,
-		customOptions: CustomPluginOptions | undefined,
-		isEntry: boolean | undefined,
-		skip: readonly { importer: string | undefined; plugin: Plugin; source: string }[] | null
-	) => Promise<ResolvedId | null>,
+	moduleLoaderResolveId: ModuleLoaderResolveId,
 	skip: readonly { importer: string | undefined; plugin: Plugin; source: string }[] | null,
 	customOptions: CustomPluginOptions | undefined,
-	isEntry: boolean
+	isEntry: boolean,
+	assertions: Record<string, string>
 ): Promise<ResolveIdResult> {
 	const pluginResult = await resolveIdViaPlugins(
 		source,
@@ -31,7 +22,8 @@ export async function resolveId(
 		moduleLoaderResolveId,
 		skip,
 		customOptions,
-		isEntry
+		isEntry,
+		assertions
 	);
 	if (pluginResult == null) {
 		throwNoFileSystem('path.resolve');

cli/help.md

@@ -36,6 +36,7 @@ Basic options:
 --exports <mode>            Specify export mode (auto, default, named, none)
 --extend                    Extend global variable defined by --name
 --no-externalLiveBindings   Do not generate code to support live bindings
+--no-externalImportAssertions Omit import assertions in "es" output
 --failAfterWarnings         Exit with an error if the build produced warnings
 --footer <text>             Code to insert at end of bundle (outside wrapper)
 --no-freeze                 Do not freeze namespace objects
@@ -68,8 +69,8 @@ Basic options:
 --no-systemNullSetters      Do not replace empty SystemJS setters with `null`
 --no-treeshake              Disable tree-shaking optimisations
 --no-treeshake.annotations  Ignore pure call annotations
---no-treeshake.moduleSideEffects Assume modules have no side-effects
---no-treeshake.propertyReadSideEffects Ignore property access side-effects
+--no-treeshake.moduleSideEffects Assume modules have no side effects
+--no-treeshake.propertyReadSideEffects Ignore property access side effects
 --no-treeshake.tryCatchDeoptimization Do not turn off try-catch-tree-shaking
 --no-treeshake.unknownGlobalSideEffects Assume unknown globals do not throw
 --waitForBundleInput        Wait for bundle input files

docs/01-command-line-reference.md

@@ -366,6 +366,7 @@ Many options have command line equivalents. In those cases, any arguments passed
 --no-esModule               Do not add __esModule property
 --exports <mode>            Specify export mode (auto, default, named, none)
 --extend                    Extend global variable defined by --name
+--no-externalImportAssertions Omit import assertions in "es" output
 --no-externalLiveBindings   Do not generate code to support live bindings
 --failAfterWarnings         Exit with an error if the build produced warnings
 --footer <text>             Code to insert at end of bundle (outside wrapper)
@@ -399,8 +400,8 @@ Many options have command line equivalents. In those cases, any arguments passed
 --no-systemNullSetters      Do not replace empty SystemJS setters with `null`
 --no-treeshake              Disable tree-shaking optimisations
 --no-treeshake.annotations  Ignore pure call annotations
---no-treeshake.moduleSideEffects Assume modules have no side-effects
---no-treeshake.propertyReadSideEffects Ignore property access side-effects
+--no-treeshake.moduleSideEffects Assume modules have no side effects
+--no-treeshake.propertyReadSideEffects Ignore property access side effects
 --no-treeshake.tryCatchDeoptimization Do not turn off try-catch-tree-shaking
 --no-treeshake.unknownGlobalSideEffects Assume unknown globals do not throw
 --waitForBundleInput        Wait for bundle input files