The arrays of a tuple literal built at run time can be changed (#486)

tslang/lib/TypeScript/MLIRGenImpl.h

@@ -1611,12 +1611,18 @@ class MLIRGenImpl
             // And a tuple literal folded to a constant with an array in it (`const st = [1, [6, 7]]`,
             // `const o = { items: [1, 2] }`): its arrays are static headers over constant data, so
             // it is widened to a tuple of heap copies once, here, like a const array literal (#479).
+            //
+            // And a tuple literal built at run time (`const nt = [x, [2, [3, 4]]]`), whose arrays
+            // are born with no count: folded, nothing counted them, and `nt[1][1].push(5)` had no
+            // reference to change the array through (#486).
             MLIRTypeHelper mth(builder.getContext(), compileOptions);
             needsIdentityStorage = mth.hasBoundMethodField(type) || isa<mlir_ts::ConstArrayType>(type)
                 || MLIRTypeHelper::isConstTupleHoldingArray(type)
                 || ((isa<mlir_ts::ArrayType>(type) || MLIRTypeHelper::isSharedHandleType(type)
                      || (readsLocalSlot(initial) && mth.ownsHeapMemory(location, type))
                      || (readsLiteralSlot(mth, location, initial) && isa<mlir_ts::TupleType>(type)
+                         && mth.ownsHeapMemory(location, type))
+                     || (initial && initial.getDefiningOp<mlir_ts::CreateTupleOp>() && isa<mlir_ts::TupleType>(type)
                          && mth.ownsHeapMemory(location, type)))
                     && !(varClass == VariableType::ConstRef)
                     && !(initial && initial.getDefiningOp<mlir_ts::SafeCastOp>()));
@@ -9698,6 +9704,12 @@ class MLIRGenImpl
             {
                 CAST(value, location, mth.convertConstTupleTypeToTupleType(value.getType()), value, genContext);
             }
+            // and a constant array (`[x, [1]]`) is an array of its own, which push and pop change:
+            // kept as the literal's constant data, `t[1].push(2)` did not resolve (#486)
+            else if (isa<mlir_ts::ConstArrayType>(value.getType()))
+            {
+                CAST(value, location, mth.convertConstArrayTypeToArrayType(value.getType()), value, genContext);
+            }
 
             fieldInfos.push_back({mlir::Attribute(), value.getType(), false, mlir_ts::AccessLevel::Public});
             arrayValues.push_back(value);

tslang/test/tester/CMakeLists.txt

@@ -348,6 +348,7 @@ tslang_add_test(NAME test-compile-00-array-rest-copy COMMAND test-runner "${PROJ
 tslang_add_test(NAME test-compile-00-arrays6 COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00array6.ts")
 tslang_add_test(NAME test-compile-00-array-static-nested COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00array_static_nested.ts")
 tslang_add_test(NAME test-compile-00-array-literal-copy COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00array_literal_copy.ts")
+tslang_add_test(NAME test-compile-00-tuple-runtime-arrays COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00tuple_runtime_arrays.ts")
 tslang_add_test(NAME test-compile-00-const-record-owned-fields COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00const_record_owned_fields.ts")
 tslang_add_test(NAME test-compile-00-array-length-valid COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00array_length_valid.ts")
 tslang_add_test(NAME test-compile-00-string-view-copy COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00string_view_copy.ts")
@@ -853,6 +854,7 @@ tslang_add_test(NAME test-jit-00-array-rest-copy COMMAND test-runner -jit "${PRO
 tslang_add_test(NAME test-jit-00-arrays6 COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00array6.ts")
 tslang_add_test(NAME test-jit-00-array-static-nested COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00array_static_nested.ts")
 tslang_add_test(NAME test-jit-00-array-literal-copy COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00array_literal_copy.ts")
+tslang_add_test(NAME test-jit-00-tuple-runtime-arrays COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00tuple_runtime_arrays.ts")
 tslang_add_test(NAME test-jit-00-const-record-owned-fields COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00const_record_owned_fields.ts")
 tslang_add_test(NAME test-jit-00-array-length-valid COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00array_length_valid.ts")
 tslang_add_test(NAME test-jit-00-string-view-copy COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00string_view_copy.ts")
@@ -1687,6 +1689,7 @@ set(TSLANG_CORPUS
     00array6.ts
     00array_static_nested.ts
     00array_literal_copy.ts
+    00tuple_runtime_arrays.ts
     00const_record_owned_fields.ts
     00array_length_valid.ts
     00string_view_copy.ts

tslang/test/tester/tests/00tuple_runtime_arrays.ts

@@ -0,0 +1,27 @@
+// The arrays of a tuple literal built at run time can be changed (#486): a constant array in it
+// (`[x, [1]]`) is a heap array of its own, not the literal's constant data that push did not
+// resolve on, and a `const` of such a tuple has storage, as a `let` has, so `nt[1][1].push(5)`
+// has a reference to change the array through and the arrays are counted.
+function g(t: [number, number[]]) { t[1].push(9); return t[1].length; }
+function main() {
+    let x = 3;
+    let t = [x, [1]];
+    t[1].push(2);
+    assert(t[1].length == 2 && t[1][1] == 2, "let, constant array in a run-time tuple");
+    const c = [x, [1]];
+    c[1].pop();
+    assert(c[1].length == 0, "const, constant array in a run-time tuple");
+    const nt = [x, [2, [3, 4]]];
+    nt[1][1].push(5);
+    assert(nt[1][1].length == 3, "const, nested");
+    const s = ["a" + x, [x, x]];
+    s[1].push(1);
+    assert(s[0] == "a3" && s[1].length == 3, "a string and an array");
+    assert(g([x, [1, 2]]) == 3, "to a tuple parameter");
+    for (let i = 0; i < 3; i++) {
+        const e = [i, [i]];
+        e[1].push(i);
+        assert(e[1].length == 2, "a new array each pass");
+    }
+    print("done.");
+}