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Transform other instances of 'this' to '_this' when in the constructor of a derived class.

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This commit is contained in:
Daniel Rosenwasser 2016-09-02 00:08:26 -07:00
parent 99f1df4c0a
commit d778e78f1e
1 changed files with 22 additions and 6 deletions
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28
src/compiler/transformers/es6.ts
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@ -722,7 +722,10 @@ namespace ts {
function addConstructor(statements: Statement[], node: ClassExpression | ClassDeclaration, extendsClauseElement: ExpressionWithTypeArguments): void {
const constructor = getFirstConstructorWithBody(node);
const hasSynthesizedSuper = hasSynthesizedDefaultSuperCall(constructor, extendsClauseElement !== undefined);
statements.push(
const savedUseCapturedThis = useCapturedThis;
useCapturedThis = true;
const constructorFunction =
createFunctionDeclaration(
/*decorators*/ undefined,
/*modifiers*/ undefined,
@ -733,8 +736,13 @@ namespace ts {
/*type*/ undefined,
transformConstructorBody(constructor, node, extendsClauseElement, hasSynthesizedSuper),
/*location*/ constructor || node
)
);
);
if (extendsClauseElement) {
setNodeEmitFlags(constructorFunction, NodeEmitFlags.CapturesThis);
}
useCapturedThis = savedUseCapturedThis;
statements.push(constructorFunction);
}
/**
@ -769,6 +777,7 @@ namespace ts {
function transformConstructorBody(constructor: ConstructorDeclaration, node: ClassDeclaration | ClassExpression, extendsClauseElement: ExpressionWithTypeArguments, hasSynthesizedSuper: boolean) {
const statements: Statement[] = [];
startLexicalEnvironment();
if (constructor) {
declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement);
addDefaultValueAssignmentsIfNeeded(statements, constructor);
@ -830,12 +839,14 @@ namespace ts {
// If this is the case, or if the class has an `extends` clause but no
// constructor, we emit a synthesized call to `_super`.
if (constructor ? hasSynthesizedSuper : extendsClauseElement) {
const actualThis = createThis();
setNodeEmitFlags(actualThis, NodeEmitFlags.NoSubstitution);
const superCall = createFunctionApply(
createIdentifier("_super"),
createThis(),
actualThis,
createIdentifier("arguments"),
);
const superReturnValueOrThis = createLogicalOr(superCall, createThis());
const superReturnValueOrThis = createLogicalOr(superCall, actualThis);
statements.push(
createVariableStatement(
@ -2504,6 +2515,9 @@ namespace ts {
// because we contain a SpreadElementExpression.
const { target, thisArg } = createCallBinding(node.expression, hoistVariableDeclaration);
if (node.expression.kind === SyntaxKind.SuperKeyword) {
setNodeEmitFlags(thisArg, NodeEmitFlags.NoSubstitution);
}
let resultingCall: CallExpression | BinaryExpression;
if (node.transformFlags & TransformFlags.ContainsSpreadElementExpression) {
// [source]
@ -2546,11 +2560,13 @@ namespace ts {
}
if (node.expression.kind === SyntaxKind.SuperKeyword) {
const actualThis = createThis();
setNodeEmitFlags(actualThis, NodeEmitFlags.NoSubstitution);
return createAssignment(
createIdentifier("_this"),
createLogicalOr(
resultingCall,
createThis()
actualThis
)
);
}