Support for import expressions (#1254)

Perryvw · web-flow · commit 570c51092709 · 2022-04-10T19:32:19.000+02:00
* Support for import expressions

* update package-lock and jest timeout
diff --git a/package-lock.json b/package-lock.json
diff --git a/src/transformation/builtins/promise.ts b/src/transformation/builtins/promise.ts
@@ -44,7 +44,7 @@ export function transformPromiseConstructorCall(
     }
 }
 
-function createStaticPromiseFunctionAccessor(functionName: string, node: ts.Node) {
+export function createStaticPromiseFunctionAccessor(functionName: string, node: ts.Node) {
     return lua.createTableIndexExpression(
         lua.createIdentifier("__TS__Promise"),
         lua.createStringLiteral(functionName),
diff --git a/src/transformation/visitors/call.ts b/src/transformation/visitors/call.ts
@@ -15,6 +15,7 @@ import { moveToPrecedingTemp, transformExpressionList } from "./expression-list"
 import { transformInPrecedingStatementScope } from "../utils/preceding-statements";
 import { getOptionalContinuationData, transformOptionalChain } from "./optional-chaining";
 import { transformLanguageExtensionCallExpression } from "./language-extensions";
+import { transformImportExpression } from "./modules/import";
 
 export type PropertyCallExpression = ts.CallExpression & { expression: ts.PropertyAccessExpression };
 
@@ -210,6 +211,10 @@ function transformElementCall(context: TransformationContext, node: ts.CallExpre
 }
 
 export const transformCallExpression: FunctionVisitor<ts.CallExpression> = (node, context) => {
+    if (node.expression.kind === ts.SyntaxKind.ImportKeyword) {
+        return transformImportExpression(node, context);
+    }
+
     if (ts.isOptionalChain(node)) {
         return transformOptionalChain(context, node);
     }
diff --git a/src/transformation/visitors/modules/import.ts b/src/transformation/visitors/modules/import.ts
@@ -1,10 +1,12 @@
 import * as path from "path";
 import * as ts from "typescript";
 import * as lua from "../../../LuaAST";
+import { createStaticPromiseFunctionAccessor } from "../../builtins/promise";
 import { FunctionVisitor, TransformationContext } from "../../context";
 import { AnnotationKind, getSymbolAnnotations } from "../../utils/annotations";
 import { createDefaultExportStringLiteral } from "../../utils/export";
 import { createHoistableVariableDeclarationStatement } from "../../utils/lua-ast";
+import { importLuaLibFeature, LuaLibFeature } from "../../utils/lualib";
 import { createSafeName } from "../../utils/safe-names";
 import { peekScope } from "../../utils/scope";
 import { transformIdentifier } from "../identifier";
@@ -161,3 +163,10 @@ export const transformImportEqualsDeclaration: FunctionVisitor<ts.ImportEqualsDe
     const expression = context.transformExpression(node.moduleReference);
     return createHoistableVariableDeclarationStatement(context, name, expression, node);
 };
+
+export const transformImportExpression: FunctionVisitor<ts.CallExpression> = (node, context) => {
+    importLuaLibFeature(context, LuaLibFeature.Promise);
+
+    const importPath = node.arguments.map(a => context.transformExpression(a));
+    return lua.createCallExpression(createStaticPromiseFunctionAccessor("resolve", node), importPath, node);
+};
diff --git a/test/cli/run.ts b/test/cli/run.ts
@@ -1,7 +1,7 @@
 import { ChildProcess, fork } from "child_process";
 import * as path from "path";
 
-jest.setTimeout(20000);
+jest.setTimeout(30000);
 
 const cliPath = path.join(__dirname, "../../src/tstl.ts");
 
diff --git a/test/unit/modules/modules.spec.ts b/test/unit/modules/modules.spec.ts
@@ -280,3 +280,14 @@ test("namespace export with unsafe Lua name", () => {
         .addExtraFile("module.ts", moduleFile)
         .expectToMatchJsResult();
 });
+
+test("import expression", () => {
+    util.testModule`
+        let result;
+        import("./module").then(m => { result = m.foo(); });
+        export { result };
+    `
+        .addExtraFile("module.ts", 'export function foo() { return "foo"; }')
+        .setOptions({ module: ts.ModuleKind.ESNext })
+        .expectToMatchJsResult();
+});

Original file line number	Diff line number	Diff line change
`@@ -44,7 +44,7 @@ export function transformPromiseConstructorCall(`
`44`	`44`	`}`
`45`	`45`	`}`
`46`	`46`
`47`		`-function createStaticPromiseFunctionAccessor(functionName: string, node: ts.Node) {`
	`47`	`+export function createStaticPromiseFunctionAccessor(functionName: string, node: ts.Node) {`
`48`	`48`	`return lua.createTableIndexExpression(`
`49`	`49`	`lua.createIdentifier("__TS__Promise"),`
`50`	`50`	`lua.createStringLiteral(functionName),`