feat(acton): support void-type parameters from Tolk 1.4 (#285)

Author: i582

server/src/e2e/tolk/testcases/inspections/CallArgumentsCountMismatchInspection.test

@@ -493,3 +493,43 @@ fun main(c: Color) {
 ------------------------------------------------------------------------
 3 2:4 to 2:20 Enum member 'Blue' is never used (tolk)
 0 10:4 to 10:14 Too many arguments in call to 'isRed', expected 0, have 1 (tolk)
+
+========================================================================
+Trailing generic void parameters can be omitted
+========================================================================
+fun println<T1, T2 = void, T3 = void>(
+    value1: T1,
+    value2: T2,
+    value3: T3,
+): void {
+    value1;
+    value2;
+    value3;
+}
+
+fun main() {
+    println(1);
+    println(1, 2);
+    println(1, 2, 3);
+}
+------------------------------------------------------------------------
+no issues
+
+========================================================================
+Generic void parameters can be omitted only at the end
+========================================================================
+fun log<T1, T2 = void>(
+    value1: T1,
+    value2: T2,
+    value3: T1,
+): void {
+    value1;
+    value2;
+    value3;
+}
+
+fun main() {
+    log(1);
+}
+------------------------------------------------------------------------
+0 11:7 to 11:8 Too few arguments in call to 'log', expected 3, have 1 (tolk)

server/src/languages/tolk/inspections/CallArgumentsCountMismatchInspection.ts

@@ -9,12 +9,15 @@ import {RecursiveVisitor} from "@server/visitor/visitor"
 import {
     Enum,
     FunctionBase,
+    Parameter,
     Struct,
     TypeAlias,
     TypeParameter,
 } from "@server/languages/tolk/psi/Decls"
 import {CallLike, NamedNode} from "@server/languages/tolk/psi/TolkNode"
 import {Reference} from "@server/languages/tolk/psi/Reference"
+import {NeverTy, TypeParameterTy, VoidTy} from "@server/languages/tolk/types/ty"
+import {typeOf} from "@server/languages/tolk/type-inference"
 
 import {Inspection, InspectionIds} from "./Inspection"
 
@@ -49,10 +52,11 @@ export class CallArgumentsCountMismatchInspection implements Inspection {
         const deltaSelf = this.isInstanceMethodCall(call) ? 1 : 0
         const args = call.arguments()
         const argsCount = args.length + deltaSelf
-        const maxParams = called.parameters().length
+        const parameters = called.parameters()
+        const maxParams = parameters.length
 
         let minParams = maxParams
-        while (minParams > 0 && called.parameters()[minParams - 1].defaultValue() !== null) {
+        while (minParams > 0 && this.canBeOmitted(parameters[minParams - 1])) {
             minParams--
         }
 
@@ -106,4 +110,20 @@ export class CallArgumentsCountMismatchInspection implements Inspection {
         // instance method call like foo.bar()
         return true
     }
+
+    private canBeOmitted(parameter: Parameter): boolean {
+        if (parameter.defaultValue() !== null) {
+            return true
+        }
+
+        const type = typeOf(parameter.node, parameter.file)?.baseType()
+        if (
+            type instanceof TypeParameterTy &&
+            (type.defaultType instanceof NeverTy || type.defaultType instanceof VoidTy)
+        ) {
+            return true
+        }
+
+        return type instanceof NeverTy || type instanceof VoidTy
+    }
 }