feat: constant evaluation of newAddress (tact-lang#237)

CHANGELOG.md

@@ -23,6 +23,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - The implicit empty `init` function is now present by default in the contract if not declared: PR [#167](https://github.com/tact-lang/tact/pull/167)
 - `@stdlib/stoppable` now imports `@stdlib/ownable` so the programmer does not have to do it separately: PR [#193](https://github.com/tact-lang/tact/pull/193)
 - Support escape sequences for strings (`\\`, `\"`, `\n`, `\r`, `\t`, `\v`, `\b`, `\f`, `\u{0}` through `\u{FFFFFF}`, `\u0000` through `\uFFFF`, `\x00` through `\xFF`): PR [#192](https://github.com/tact-lang/tact/pull/192)
+- `newAddress` function now evaluates to a constant value if possible: PR [#237](https://github.com/tact-lang/tact/pull/237)
 
 ### Fixed
 

src/test/feature-constants.spec.ts

@@ -0,0 +1,35 @@
+import { toNano } from "@ton/core";
+import { ContractSystem } from "@tact-lang/emulator";
+import { __DANGER_resetNodeId } from "../grammar/ast";
+import { ConstantTester } from "./features/output/constants_ConstantTester";
+
+describe("feature-constants", () => {
+    beforeEach(() => {
+        __DANGER_resetNodeId();
+    });
+    it("should implement constants correctly", async () => {
+        // Init
+        const system = await ContractSystem.create();
+        const treasure = system.treasure("treasure");
+        const contract = system.open(await ConstantTester.fromInit());
+        await contract.send(treasure, { value: toNano("10") }, null);
+        await system.run();
+
+        // Check methods
+        expect(await contract.getSomething1()).toEqual(11n);
+        expect(await contract.getSomething2()).toBeNull();
+        expect(await contract.getSomething3()).toEqual(toNano("123"));
+        expect(await contract.getSomething4()).toEqual(toNano("456"));
+        expect(await contract.getSomething5()).toEqual("Hello world!");
+        expect(await contract.getSomething6()).toEqual(10n);
+        expect(await contract.getSomething7()).toEqual(5n);
+        expect(await contract.getSomething8()).toEqual(4n);
+        expect((await contract.getSomething9()).toRawString()).toEqual(
+            "0:4a81708d2cf7b15a1b362fbf64880451d698461f52f05f145b36c08517d76873",
+        );
+        expect((await contract.getSomething10()).toRawString()).toEqual(
+            "0:4a81708d2cf7b15a1b362fbf64880451d698461f52f05f145b36c08517d76873",
+        );
+        expect(await contract.getGlobalConst()).toEqual(100n);
+    });
+});

src/test/features/constants.tact

@@ -9,11 +9,17 @@ contract ConstantTester {
     const something6: Int = 10 * 1;
     const something7: Int = 10 >> 1;
     const something8: Int = (2 + 4) & 4;
+    const something9: Address = address("UQBKgXCNLPexWhs2L79kiARR1phGH1LwXxRbNsCFF9doczSI");
+    const something10: Address = newAddress(0, 0x4a81708d2cf7b15a1b362fbf64880451d698461f52f05f145b36c08517d76873);
 
     init() {
 
     }
 
+    receive() {
+
+    }
+
     get fun something1(): Int {
         return self.something1;
     }
@@ -46,6 +52,14 @@ contract ConstantTester {
         return self.something8;
     }
 
+    get fun something9(): Address {
+        return self.something9;
+    }
+
+    get fun something10(): Address {
+        return self.something10;
+    }
+
     get fun globalConst(): Int {
         return someGlobalConst;
     }

src/types/resolveConstantValue.ts

@@ -121,6 +121,29 @@ function reduceAddress(ast: ASTExpression, ctx: CompilerContext): Address {
                 }
                 return address;
             }
+        } else if (ast.name === "newAddress") {
+            if (ast.args.length === 2) {
+                const wc = reduceInt(ast.args[0]);
+                const addr = Buffer.from(
+                    reduceInt(ast.args[1]).toString(16),
+                    "hex",
+                );
+                if (wc !== 0n && wc !== -1n) {
+                    throwError(
+                        `Expected workchain to equal 0 or -1, received: ${wc}`,
+                        ast.ref,
+                    );
+                }
+                if (!enabledMasterchain(ctx)) {
+                    if (wc !== 0n) {
+                        throwError(
+                            `Address ${wc}:${addr} from masterchain are not enabled for this contract`,
+                            ast.ref,
+                        );
+                    }
+                }
+                return new Address(parseInt(wc.toString()), addr);
+            }
         }
     }
     throwError("Cannot reduce expression to a constant Address", ast.ref);