fix(typechecker): self-inheritance case for contracts and traits (#3094)

Author: hazyone

dev-docs/CHANGELOG.md

@@ -7,18 +7,32 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-- [fix] Added fixed-bytes support to bounced message size calculations
+### Language features
+
+- [fix] Disallow self-inheritance for contracts and traits: PR [#3094](https://github.com/tact-lang/tact/pull/3094)
+- [fix] Added fixed-bytes support to bounced message size calculations: PR [#3129](https://github.com/tact-lang/tact/pull/3129)
 
 ### Docs
 
 - Changed the title of the "Gas-expensive" badge to "500+ gas" to avoid confusion when discussing relative gas-efficiency: PR [#3120](https://github.com/tact-lang/tact/pull/3120)
 
+### Release contributors
+
+- [hazyone](https://github.com/hazyone)
+- [lordivash](https://github.com/lordivash)
+- [Novus Nota](https://github.com/novusnota)
+
 ## [1.6.10] - 2025-05-16
 
 ### Infrastructure
 
 - [fix] Explicit dependencies to fix Blueprint integration: PR [#3088](https://github.com/tact-lang/tact/pull/3088)
 
+### Release contributors
+
+- [Petr Makhnev](https://github.com/i582)
+- [verytactical](https://github.com/verytactical)
+
 ## [1.6.9] - 2025-05-16
 
 ### TypeScript third-party API

spell/cspell-list.txt

@@ -22,6 +22,7 @@ cheatsheet
 Cheatsheet
 cheatsheets
 Cheatsheets
+chksgn
 cleanall
 CNFT
 codegen
@@ -30,7 +31,6 @@ Compilables
 comptime
 Comptime
 CSBT
-chksgn
 Daniil
 Danil
 decompilation
@@ -42,18 +42,18 @@ decompiles
 decompiling
 dentry
 Descr
+dictpush
 disasm
 divmod
 dnsresolve
 Domínguez
 dstr
-dictpush
 elseifnot
 Eltociear
 Epva
 errno
-Excno
 Esorat
+Excno
 extracurrency
 flamegraph
 flamegraphs
@@ -67,6 +67,7 @@ Georgiy
 getsimpleforwardfee
 gettest
 guarantor
+hazyone
 Héctor
 hehe
 heisenbugs
@@ -79,8 +80,8 @@ infixl
 infixr
 initof
 injectivity
-Ints
 Intelli
+Ints
 ipfs
 IPFS
 ipld
@@ -107,6 +108,7 @@ Liskov
 llm
 llms
 logomark
+lordivash
 lparen
 lvalue
 lvalues

src/types/__snapshots__/resolveDescriptors.spec.ts.snap

@@ -315,6 +315,24 @@ exports[`resolveDescriptors should fail descriptors for contract-receiver-struct
 "
 `;
 
+exports[`resolveDescriptors should fail descriptors for contract-self-inheritance-combined 1`] = `
+"<unknown>:7:1: Self-inheritance is not allowed
+  6 | contract B {}
+> 7 | contract C with A, B, C {}
+      ^~~~~~~~~~~~~~~~~~~~~~~~~~
+  8 | 
+"
+`;
+
+exports[`resolveDescriptors should fail descriptors for contract-with-self-inheritance 1`] = `
+"<unknown>:5:1: Self-inheritance is not allowed
+  4 | 
+> 5 | contract A with A {
+      ^~~~~~~~~~~~~~~~~~~
+  6 | }
+"
+`;
+
 exports[`resolveDescriptors should fail descriptors for contract-without-as-typed-field-inherited-with-it 1`] = `
 "<unknown>:10:5: Trait "Foo" requires field "f" of type "Int", but "Int as coins" given
    9 | contract SomeContract with Foo {
@@ -1338,6 +1356,23 @@ exports[`resolveDescriptors should fail descriptors for trait-with-as-typed-int2
 "
 `;
 
+exports[`resolveDescriptors should fail descriptors for trait-with-self-inheritance 1`] = `
+"<unknown>:1:1: Self-inheritance is not allowed
+> 1 | trait A with A {
+      ^~~~~~~~~~~~~~~~
+  2 | }
+"
+`;
+
+exports[`resolveDescriptors should fail descriptors for trait-with-self-inheritance-combined 1`] = `
+"<unknown>:3:1: Self-inheritance is not allowed
+  2 | trait B {}
+> 3 | trait C with A, B, C {}
+      ^~~~~~~~~~~~~~~~~~~~~~~
+  4 | 
+"
+`;
+
 exports[`resolveDescriptors should fail descriptors for trait-without-as-typed-field-inherited-with-it 1`] = `
 "<unknown>:10:5: Trait "Foo" requires field "f" of type "Int", but "Int as int32" given
    9 | trait SomeTrait with Foo {

src/types/resolveDescriptors.ts

@@ -1638,10 +1638,14 @@ export function resolveDescriptors(ctx: CompilerContext, Ast: FactoryAst) {
             // Check there are no duplicates in the _immediately_ inherited traits
             const traitSet: Set<string> = new Set(t.ast.traits.map(idText));
             if (traitSet.size !== t.ast.traits.length) {
-                const aggregateType =
-                    t.ast.kind === "contract" ? "contract" : "trait";
                 throwCompilationError(
-                    `The list of inherited traits for ${aggregateType} "${t.name}" has duplicates`,
+                    `The list of inherited traits for ${t.ast.kind} "${t.name}" has duplicates`,
+                    t.ast.loc,
+                );
+            }
+            if (traitSet.has(t.name)) {
+                throwCompilationError(
+                    `Self-inheritance is not allowed`,
                     t.ast.loc,
                 );
             }

src/types/test-failed/contract-self-inheritance-combined.tact

@@ -0,0 +1,7 @@
+trait BaseTrait {
+
+}
+
+contract A {}
+contract B {}
+contract C with A, B, C {}

src/types/test-failed/contract-with-self-inheritance.tact

@@ -0,0 +1,7 @@
+trait BaseTrait {
+
+}
+
+contract A with A {
+}
+

src/types/test-failed/trait-with-self-inheritance-combined.tact

@@ -0,0 +1,3 @@
+trait A {}
+trait B {}
+trait C with A, B, C {}

src/types/test-failed/trait-with-self-inheritance.tact

@@ -0,0 +1,2 @@
+trait A with A {
+}