Correctly place class member preceding instances in the constructor always (#1211)

Perryvw · web-flow · commit f23ea3e3ae96 · 2022-01-16T17:50:22.000+01:00
diff --git a/src/transformation/visitors/class/members/constructor.ts b/src/transformation/visitors/class/members/constructor.ts
@@ -2,7 +2,6 @@ import * as ts from "typescript";
 import * as lua from "../../../../LuaAST";
 import { TransformationContext } from "../../../context";
 import { createSelfIdentifier } from "../../../utils/lua-ast";
-import { transformInPrecedingStatementScope } from "../../../utils/preceding-statements";
 import { popScope, pushScope, ScopeType } from "../../../utils/scope";
 import { transformFunctionBodyContent, transformFunctionBodyHeader, transformParameters } from "../../function";
 import { transformIdentifier } from "../../identifier";
@@ -44,9 +43,7 @@ export function transformConstructorDeclaration(
     // Check for field declarations in constructor
     const constructorFieldsDeclarations = statement.parameters.filter(p => p.modifiers !== undefined);
 
-    const [fieldsPrecedingStatements, classInstanceFields] = transformInPrecedingStatementScope(context, () =>
-        transformClassInstanceFields(context, instanceFields)
-    );
+    const classInstanceFields = transformClassInstanceFields(context, instanceFields);
 
     // If there are field initializers and the first statement is a super call,
     // move super call between default assignments and initializers
@@ -81,7 +78,6 @@ export function transformConstructorDeclaration(
         // else { TypeScript error: A parameter property may not be declared using a binding pattern }
     }
 
-    bodyWithFieldInitializers.push(...fieldsPrecedingStatements);
     bodyWithFieldInitializers.push(...classInstanceFields);
 
     bodyWithFieldInitializers.push(...body);
diff --git a/src/transformation/visitors/class/members/fields.ts b/src/transformation/visitors/class/members/fields.ts
@@ -2,6 +2,7 @@ import * as ts from "typescript";
 import * as lua from "../../../../LuaAST";
 import { TransformationContext } from "../../../context";
 import { createSelfIdentifier } from "../../../utils/lua-ast";
+import { transformInPrecedingStatementScope } from "../../../utils/preceding-statements";
 import { transformPropertyName } from "../../literal";
 import { createDecoratingExpression, transformDecoratorExpression } from "../decorators";
 import { transformMemberExpressionOwnerName } from "./method";
@@ -30,18 +31,22 @@ export function transformClassInstanceFields(
     const statements: lua.Statement[] = [];
 
     for (const f of instanceFields) {
-        // Get identifier
-        const fieldName = transformPropertyName(context, f.name);
+        const [precedingStatements, statement] = transformInPrecedingStatementScope(context, () => {
+            // Get identifier
+            const fieldName = transformPropertyName(context, f.name);
 
-        const value = f.initializer ? context.transformExpression(f.initializer) : undefined;
+            const value = f.initializer ? context.transformExpression(f.initializer) : undefined;
 
-        // self[fieldName]
-        const selfIndex = lua.createTableIndexExpression(createSelfIdentifier(), fieldName);
+            // self[fieldName]
+            const selfIndex = lua.createTableIndexExpression(createSelfIdentifier(), fieldName);
 
-        // self[fieldName] = value
-        const assignClassField = lua.createAssignmentStatement(selfIndex, value, f);
+            // self[fieldName] = value
+            const assignClassField = lua.createAssignmentStatement(selfIndex, value, f);
 
-        statements.push(assignClassField);
+            return assignClassField;
+        });
+
+        statements.push(...precedingStatements, statement);
     }
 
     return statements;
diff --git a/test/unit/precedingStatements.spec.ts b/test/unit/precedingStatements.spec.ts
@@ -635,3 +635,14 @@ test("class member initializers", () => {
         return [inst.myField, inst.foo];
     `.expectToMatchJsResult();
 });
+
+test("class member initializers in extended class", () => {
+    util.testFunction`
+        class A {}
+        class MyClass extends A {
+            myField = false ?? true;
+        }
+        const inst = new MyClass();
+        return inst.myField;
+    `.expectToMatchJsResult();
+});
