if f is a contextually typed function expression (section 4.9.3), the inferred return type is the union type (section 3.3.4) of the types of the return statement expressions in the function body, ignoring return statements with no expressions. Otherwise, the inferred return type is the first of the types of the return statement expressions in the function body that is a supertype (section 3.8.3) of each of the others, ignoring return statements with no expressions. A compile-time error occurs if no return statement expression has a type that is a supertype of each of the others.
151 lines
No EOL
6.3 KiB
Text
151 lines
No EOL
6.3 KiB
Text
tests/cases/conformance/functions/functionImplementationErrors.ts(2,10): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(6,10): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(10,10): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(16,10): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(25,16): error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(30,17): error TS2373: Initializer of parameter 'n' cannot reference identifier 'm' declared after it.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(35,17): error TS2373: Initializer of parameter 'n' cannot reference identifier 'm' declared after it.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(40,28): error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(49,1): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(53,10): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(57,11): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(61,1): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(65,11): error TS2354: No best common type exists among return expressions.
|
|
tests/cases/conformance/functions/functionImplementationErrors.ts(69,11): error TS2354: No best common type exists among return expressions.
|
|
|
|
|
|
==== tests/cases/conformance/functions/functionImplementationErrors.ts (14 errors) ====
|
|
// FunctionExpression with no return type annotation with multiple return statements with unrelated types
|
|
var f1 = function () {
|
|
~~~~~~~~~~~~~
|
|
return '';
|
|
~~~~~~~~~~~~~~
|
|
return 3;
|
|
~~~~~~~~~~~~~
|
|
};
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
var f2 = function x() {
|
|
~~~~~~~~~~~~~~
|
|
return '';
|
|
~~~~~~~~~~~~~~
|
|
return 3;
|
|
~~~~~~~~~~~~~
|
|
};
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
var f3 = () => {
|
|
~~~~~~~
|
|
return '';
|
|
~~~~~~~~~~~~~~
|
|
return 3;
|
|
~~~~~~~~~~~~~
|
|
};
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
|
|
// FunctionExpression with no return type annotation with return branch of number[] and other of string[]
|
|
var f4 = function () {
|
|
~~~~~~~~~~~~~
|
|
if (true) {
|
|
~~~~~~~~~~~~~~~
|
|
return [''];
|
|
~~~~~~~~~~~~~~~~~~~~
|
|
} else {
|
|
~~~~~~~~~~~~
|
|
return [1];
|
|
~~~~~~~~~~~~~~~~~~~
|
|
}
|
|
~~~~~
|
|
}
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
|
|
// Function implemetnation with non -void return type annotation with no return
|
|
function f5(): number {
|
|
~~~~~~
|
|
!!! error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
|
|
}
|
|
|
|
var m;
|
|
// Function signature with parameter initializer referencing in scope local variable
|
|
function f6(n = m) {
|
|
~
|
|
!!! error TS2373: Initializer of parameter 'n' cannot reference identifier 'm' declared after it.
|
|
var m = 4;
|
|
}
|
|
|
|
// Function signature with initializer referencing other parameter to the right
|
|
function f7(n = m, m?) {
|
|
~
|
|
!!! error TS2373: Initializer of parameter 'n' cannot reference identifier 'm' declared after it.
|
|
}
|
|
|
|
// FunctionExpression with non -void return type annotation with a throw, no return, and other code
|
|
// Should be error but isn't
|
|
undefined === function (): number {
|
|
~~~~~~
|
|
!!! error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.
|
|
throw undefined;
|
|
var x = 4;
|
|
};
|
|
|
|
class Base { private x; }
|
|
class AnotherClass { private y; }
|
|
class Derived1 extends Base { private m; }
|
|
class Derived2 extends Base { private n; }
|
|
function f8() {
|
|
~~~~~~~~~~~~~~~
|
|
return new Derived1();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
return new Derived2();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
}
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
var f9 = function () {
|
|
~~~~~~~~~~~~~
|
|
return new Derived1();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
return new Derived2();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
};
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
var f10 = () => {
|
|
~~~~~~~
|
|
return new Derived1();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
return new Derived2();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
};
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
function f11() {
|
|
~~~~~~~~~~~~~~~~
|
|
return new Base();
|
|
~~~~~~~~~~~~~~~~~~~~~~
|
|
return new AnotherClass();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
}
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
var f12 = function () {
|
|
~~~~~~~~~~~~~
|
|
return new Base();
|
|
~~~~~~~~~~~~~~~~~~~~~~
|
|
return new AnotherClass();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
};
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
var f13 = () => {
|
|
~~~~~~~
|
|
return new Base();
|
|
~~~~~~~~~~~~~~~~~~~~~~
|
|
return new AnotherClass();
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
};
|
|
~
|
|
!!! error TS2354: No best common type exists among return expressions.
|
|
|