Fix const and destructuring locals in modules imported as source

tslang/lib/TypeScript/MLIRGenVariables.cpp

@@ -765,7 +765,14 @@ namespace mlirgen
 #endif
 
         auto initFunc = [&](mlir::Location location, const GenContext &genContext) {
-            if (declarationMode)
+            // A module imported as source only declares what it defines, so a module-level
+            // variable gets its type and no initializer code. Not a local: a function body is only
+            // walked here to infer types (a dummy run, see mlirGenFunctionBody) and its IR is
+            // discarded, so its initializers may produce real values - and must. A `const` binds
+            // its name to that value, and a destructuring pattern reads its elements from it:
+            // without one, reading the const failed with "can't resolve name" and destructuring
+            // with "failed statement" or a crash.
+            if (declarationMode && !genContext.funcOp)
             {
                 auto [t, b, p] = evaluateTypeAndInit(item, genContext);
                 return std::make_tuple(t, mlir::Value(), p ? TypeProvided::Yes : TypeProvided::No);

tslang/test/tester/CMakeLists.txt

@@ -975,6 +975,7 @@ add_test(NAME test-compile-export-import-class-interface COMMAND test-runner "${
 # static two-module form had no rc/none coverage at all, which is why the leak it fixes
 # went unmeasured for so long.
 add_test(NAME test-compile-export-import-owned-returns COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/import_owned_returns.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_owned_returns.ts")
+add_test(NAME test-compile-export-import-const-locals COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/import_const_locals.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_const_locals.ts")
 add_test(NAME test-compile-rc-export-import-owned-returns COMMAND test-runner -mm=rc "${PROJECT_SOURCE_DIR}/test/tester/tests/import_owned_returns.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_owned_returns.ts")
 add_test(NAME test-compile-none-export-import-owned-returns COMMAND test-runner -mm=none "${PROJECT_SOURCE_DIR}/test/tester/tests/import_owned_returns.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_owned_returns.ts")
 add_test(NAME test-compile-export-import-class-extends COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/import_class_extends.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_class_extends.ts")
@@ -1058,6 +1059,7 @@ add_test(NAME test-compile-shared-export-import-owned-returns COMMAND test-runne
 # see the importer's array. Under -jit this failed (2000 of 2000 freed) while TypeScriptRuntime.dll
 # linked Boehm statically beside a library on gc.dll.
 add_test(NAME test-compile-shared-export-import-gc-single-collector COMMAND test-runner -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_gc_single_collector.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_gc_single_collector.ts")
+add_test(NAME test-compile-shared-export-import-const-locals COMMAND test-runner -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_const_locals.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_const_locals.ts")
 add_test(NAME test-compile-shared-export-import-class-extends COMMAND test-runner -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_class_extends.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_class_extends.ts")
 add_test(NAME test-compile-shared-export-import-class-extends-implements-diamond COMMAND test-runner -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_class_extends_implements_diamond.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_class_extends_implements_diamond.ts")
 add_test(NAME test-compile-shared-export-import-class-extends-multilevel COMMAND test-runner -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_class_extends_multilevel.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_class_extends_multilevel.ts")
@@ -1140,6 +1142,7 @@ add_test(NAME test-jit-shared-export-import-class-interface COMMAND test-runner
 add_test(NAME test-jit-shared-export-import-object-literal-with-class-types COMMAND test-runner -jit -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_object_literal_with_class_types.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_object_literal_with_class_types.ts")
 add_test(NAME test-jit-shared-export-import-owned-returns COMMAND test-runner -jit -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_owned_returns.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_owned_returns.ts")
 add_test(NAME test-jit-shared-export-import-gc-single-collector COMMAND test-runner -jit -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_gc_single_collector.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_gc_single_collector.ts")
+add_test(NAME test-jit-shared-export-import-const-locals COMMAND test-runner -jit -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_const_locals.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_const_locals.ts")
 add_test(NAME test-jit-shared-export-import-class-extends COMMAND test-runner -jit -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_class_extends.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_class_extends.ts")
 add_test(NAME test-jit-shared-export-import-class-extends-multilevel COMMAND test-runner -jit -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_class_extends_multilevel.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_class_extends_multilevel.ts")
 add_test(NAME test-jit-shared-export-import-class-extends-implements-diamond COMMAND test-runner -jit -shared "${PROJECT_SOURCE_DIR}/test/tester/tests/import_class_extends_implements_diamond.ts" "${PROJECT_SOURCE_DIR}/test/tester/tests/export_class_extends_implements_diamond.ts")

tslang/test/tester/tests/export_const_locals.ts

@@ -0,0 +1,65 @@
+// The library side of import_const_locals.ts. Every function reads a `const` local. When a module
+// imports this file as source (no shared library beside it), its bodies are compiled only to
+// infer types, with no values - and a `const` used to bind its name to that missing value, so the
+// importer failed with "can't resolve name". `let` was never affected.
+
+export function plainConst(n: number): number {
+    const s = n + 1;
+    return s;
+}
+
+// No return type: it is inferred from the const, so the importer must infer the same one the
+// library does - a const read back as its storage reference instead gave `ref<number>` here.
+export function inferredFromConst(n: number) {
+    const s = n + 2;
+    return s;
+}
+
+export function stringConst(n: number): string {
+    const s = `v-${n}`;
+    return s;
+}
+
+export function constInLoop(n: number): number {
+    let total = 0;
+    for (let j = 0; j < n; j++) {
+        const s = j * 2;
+        total = total + s;
+    }
+
+    return total;
+}
+
+export function constInBlock(n: number): number {
+    let total = 0;
+    if (n > 0) {
+        const s = `${n}`;
+        total = total + s.length;
+    }
+
+    return total;
+}
+
+export class WithConst {
+    method(n: number) {
+        const s = n + 10;
+        return s;
+    }
+}
+
+export function arrayDestructuring(n: number): number {
+    const [a, b] = [n, n + 1];
+    return a + b;
+}
+
+export function objectDestructuring(n: number): number {
+    const { x, y } = { x: n, y: 5 };
+    return x + y;
+}
+
+namespace NS {
+    export function namespaceConst(n: number): number {
+        const s = `${n}-${n}`;
+        return s.length;
+    }
+}

tslang/test/tester/tests/import_const_locals.ts

@@ -0,0 +1,18 @@
+import './export_const_locals'
+
+// A module imported as source must compile when its functions read `const` locals.
+// See export_const_locals.ts.
+
+function main() {
+    assert(plainConst(1) == 2, "plainConst");
+    assert(inferredFromConst(3) == 5, "inferredFromConst");
+    assert(stringConst(7) == "v-7", "stringConst");
+    assert(constInLoop(4) == 12, "constInLoop");
+    assert(constInBlock(123) == 3, "constInBlock");
+    assert(new WithConst().method(5) == 15, "WithConst.method");
+    assert(arrayDestructuring(3) == 7, "arrayDestructuring");
+    assert(objectDestructuring(4) == 9, "objectDestructuring");
+    assert(NS.namespaceConst(12) == 5, "NS.namespaceConst");
+
+    print("done.");
+}