Skip to content

fix: covariant method overrides break Go compilation #4967

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 4 commits into from
Oct 28, 2025
Merged

fix: covariant method overrides break Go compilation #4967

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
523c340
fix: compile Go code by default
rix0rrr Oct 28, 2025
9d58db7
reflect and tests
mrgrain Oct 28, 2025
3403601
fixes
mrgrain Oct 28, 2025
ee881f4
snaps
mrgrain Oct 28, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
64 changes: 64 additions & 0 deletions packages/@jsii/go-runtime-test/project/covariantoverrides_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,64 @@
package tests

import (
"testing"

"github.com/aws/jsii/jsii-calc/go/jsiicalc/v3/covariantoverrides/classoverrides"
)

func TestBase(t *testing.T) {
base := classoverrides.NewBase()
if *base.Something().Name() != "Superclass" {
t.Errorf("Expected Superclass, got %s", *base.Something().Name())
}
if *base.CreateSomething().SayHello() != "Hello Superclass" {
t.Errorf("Expected 'Hello Superclass', got %s", *base.CreateSomething().SayHello())
}
}

func TestMiddle(t *testing.T) {
middle := classoverrides.NewMiddle()
if *middle.Something().Name() != "Superclass" {
t.Errorf("Expected Superclass, got %s", *middle.Something().Name())
}
if *middle.CreateSomething().SayHello() != "Hello Superclass" {
t.Errorf("Expected 'Hello Superclass', got %s", *middle.CreateSomething().SayHello())
}
}

func TestDerived(t *testing.T) {
derived := classoverrides.NewDerived()
if *derived.Something().Name() != "SubSubclass" {
t.Errorf("Expected SubSubclass, got %s", *derived.Something().Name())
}
created := derived.CreateSomething()
if *created.Name() != "SubSubclass" {
t.Errorf("Expected SubSubclass, got %s", *created.Name())
}
if *created.SayHello() != "Hello SubSubclass" {
t.Errorf("Expected 'Hello SubSubclass', got %s", *created.SayHello())
}
}

func TestPolymorphism(t *testing.T) {
derived := classoverrides.NewDerived()
var base classoverrides.IBase = derived

if *base.Something().Name() != "SubSubclass" {
t.Errorf("Expected SubSubclass, got %s", *base.Something().Name())
}
}

func consumeSubSubclass(s classoverrides.SubSubclass) string {
return *s.Name()
}

func TestTypeCasting(t *testing.T) {
derived := classoverrides.NewDerived()
superclassResult := derived.Something()
name := consumeSubSubclass(superclassResult.(classoverrides.SubSubclass))
if name != "SubSubclass" {
t.Errorf("Expected SubSubclass, got %s", name)
}
}

26 changes: 23 additions & 3 deletions packages/jsii-calc/lib/covariant-overrides/class-overrides.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,13 +6,33 @@
*/

/** Base class in the inheritance hierarchy */
export class Superclass {}
export class Superclass {
public name = 'Superclass';
public sayHello(): string {
return 'Hello Superclass';
}
}

/** Derived class that extends Superclass */
export class Subclass extends Superclass {}
export class Subclass extends Superclass {
public name = 'Subclass';
public sayHello(): string {
return 'Hello Subclass';
}
}

/** Further derived class that extends Subclass */
export class SubSubclass extends Subclass {}
export class SubSubclass extends Subclass {
/**
* Ensures this class is different than its parent.
*/
public unique = 'yes';

public name = 'SubSubclass';
public sayHello(): string {
return 'Hello SubSubclass';
}
}

export interface IBase {
readonly something: Superclass;
Expand Down
144 changes: 129 additions & 15 deletions packages/jsii-calc/test/assembly.jsii
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -16749,7 +16749,7 @@
"kind": "class",
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 22
"line": 42
},
"methods": [
{
Expand All @@ -16758,7 +16758,7 @@
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 26
"line": 46
},
"name": "createSomething",
"returns": {
Expand All @@ -16778,7 +16778,7 @@
"immutable": true,
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 24
"line": 44
},
"name": "list",
"type": {
Expand All @@ -16797,7 +16797,7 @@
"immutable": true,
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 23
"line": 43
},
"name": "something",
"overrides": "jsii-calc.covariantOverrides.classOverrides.IBase",
Expand Down Expand Up @@ -16825,7 +16825,7 @@
"kind": "class",
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 42
"line": 62
},
"methods": [
{
Expand All @@ -16834,7 +16834,7 @@
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 48
"line": 68
},
"name": "createSomething",
"overrides": "jsii-calc.covariantOverrides.classOverrides.Base",
Expand All @@ -16855,7 +16855,7 @@
"immutable": true,
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 45
"line": 65
},
"name": "list",
"overrides": "jsii-calc.covariantOverrides.classOverrides.Base",
Expand All @@ -16875,7 +16875,7 @@
"immutable": true,
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 44
"line": 64
},
"name": "something",
"overrides": "jsii-calc.covariantOverrides.classOverrides.Base",
Expand All @@ -16895,7 +16895,7 @@
"kind": "interface",
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 17
"line": 37
},
"name": "IBase",
"namespace": "covariantOverrides.classOverrides",
Expand All @@ -16908,7 +16908,7 @@
"immutable": true,
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 18
"line": 38
},
"name": "something",
"type": {
Expand All @@ -16934,7 +16934,7 @@
"kind": "class",
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 32
"line": 52
},
"name": "Middle",
"namespace": "covariantOverrides.classOverrides",
Expand All @@ -16945,7 +16945,7 @@
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 33
"line": 53
},
"name": "addUnrelatedMember",
"type": {
Expand All @@ -16971,10 +16971,58 @@
"kind": "class",
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 15
"line": 25
},
"methods": [
{
"docs": {
"stability": "stable"
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 32
},
"name": "sayHello",
"overrides": "jsii-calc.covariantOverrides.classOverrides.Subclass",
"returns": {
"type": {
"primitive": "string"
}
}
}
],
"name": "SubSubclass",
"namespace": "covariantOverrides.classOverrides",
"properties": [
{
"docs": {
"stability": "stable"
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 31
},
"name": "name",
"overrides": "jsii-calc.covariantOverrides.classOverrides.Subclass",
"type": {
"primitive": "string"
}
},
{
"docs": {
"stability": "stable",
"summary": "Ensures this class is different than its parent."
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 29
},
"name": "unique",
"type": {
"primitive": "string"
}
}
],
"symbolId": "lib/covariant-overrides/class-overrides:SubSubclass"
},
"jsii-calc.covariantOverrides.classOverrides.Subclass": {
Expand All @@ -16993,10 +17041,44 @@
"kind": "class",
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 12
"line": 17
},
"methods": [
{
"docs": {
"stability": "stable"
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 19
},
"name": "sayHello",
"overrides": "jsii-calc.covariantOverrides.classOverrides.Superclass",
"returns": {
"type": {
"primitive": "string"
}
}
}
],
"name": "Subclass",
"namespace": "covariantOverrides.classOverrides",
"properties": [
{
"docs": {
"stability": "stable"
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 18
},
"name": "name",
"overrides": "jsii-calc.covariantOverrides.classOverrides.Superclass",
"type": {
"primitive": "string"
}
}
],
"symbolId": "lib/covariant-overrides/class-overrides:Subclass"
},
"jsii-calc.covariantOverrides.classOverrides.Superclass": {
Expand All @@ -17016,8 +17098,40 @@
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 9
},
"methods": [
{
"docs": {
"stability": "stable"
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 11
},
"name": "sayHello",
"returns": {
"type": {
"primitive": "string"
}
}
}
],
"name": "Superclass",
"namespace": "covariantOverrides.classOverrides",
"properties": [
{
"docs": {
"stability": "stable"
},
"locationInModule": {
"filename": "lib/covariant-overrides/class-overrides.ts",
"line": 10
},
"name": "name",
"type": {
"primitive": "string"
}
}
],
"symbolId": "lib/covariant-overrides/class-overrides:Superclass"
},
"jsii-calc.homonymousForwardReferences.bar.Consumer": {
Expand Down Expand Up @@ -19672,5 +19786,5 @@
"intersection-types"
],
"version": "3.20.120",
"fingerprint": "bgdsE4i6uPRf3d8FnIARS1FO4PilyDwzanABdH+SqIg="
"fingerprint": "6Vy4e6a5fe6HlMnZVVfUxQ6kP2NgQEfEjwgiDHv/Ssw="
}
9 changes: 7 additions & 2 deletions packages/jsii-pacmak/lib/targets/go.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -56,8 +56,13 @@ export class Golang extends Target {
return Promise.reject(e);
}

if (process.env.JSII_BUILD_GO) {
// This step is taken to ensure that the generated code is compilable
// This step is taken to ensure that the generated code is compilable
// Do it by default, because we didn't use to and that was masking a code generation
// problem.
const doBuild = !['false', '0', 'no'].includes(
process.env.JSII_BUILD_GO ?? '1',
);
if (doBuild) {
await go('build', ['-modfile', localGoMod.path, './...'], {
cwd: pkgDir,
});
Expand Down
Loading
Loading