A for condition that tests an optional value is made a boolean

tslang/lib/TypeScript/MLIRGenStatements.cpp

@@ -840,6 +840,12 @@ namespace mlirgen
         auto conditionValue = V(result);
         if (conditionValue)
         {
+            // a truthiness test (`for (let n = head; n; n = n.next)`) is made a boolean as in mlirGen(WhileStatement)
+            if (conditionValue.getType() != getBooleanType())
+            {
+                CAST(conditionValue, location, getBooleanType(), conditionValue, loopGenContext);
+            }
+
             builder.create<mlir_ts::ConditionOp>(location, conditionValue, mlir::ValueRange{});
         }
         else

tslang/test/tester/CMakeLists.txt

@@ -355,6 +355,7 @@ tslang_add_test(NAME test-compile-00-array-insert-functions COMMAND test-runner
 tslang_add_test(NAME test-compile-00-await-void COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00await_void.ts")
 tslang_add_test(NAME test-compile-00-for-await-sequential COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00for_await_sequential.ts")
 tslang_add_test(NAME test-compile-00-for-await-control COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00for_await_control.ts")
+tslang_add_test(NAME test-compile-00-for-optional-class-condition COMMAND test-runner "${PROJECT_SOURCE_DIR}/test/tester/tests/00for_optional_class_condition.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 "${PROJECT_SOURCE_DIR}/test/tester/tests/00string_view_copy.ts")
@@ -867,6 +868,7 @@ tslang_add_test(NAME test-jit-00-array-insert-functions COMMAND test-runner -jit
 tslang_add_test(NAME test-jit-00-await-void COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00await_void.ts")
 tslang_add_test(NAME test-jit-00-for-await-sequential COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00for_await_sequential.ts")
 tslang_add_test(NAME test-jit-00-for-await-control COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00for_await_control.ts")
+tslang_add_test(NAME test-jit-00-for-optional-class-condition COMMAND test-runner -jit "${PROJECT_SOURCE_DIR}/test/tester/tests/00for_optional_class_condition.ts")
 tslang_add_test(NAME test-jit-00-const-record-owned-fields COMMAND test-runner -jit "${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")
@@ -1708,6 +1710,7 @@ set(TSLANG_CORPUS
     00await_void.ts
     00for_await_sequential.ts
     00for_await_control.ts
+    00for_optional_class_condition.ts
     00const_record_owned_fields.ts
     00array_length_valid.ts
     00string_view_copy.ts

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

@@ -0,0 +1,85 @@
+// a `for` condition that is a bare truthiness test of an optional value (`for (let n = head; n; n = n.next)`)
+// went to ts.Condition unconverted and failed module verification; `while` and `if` made it a boolean first
+class Node {
+    constructor(public value: number, public next: Node | undefined) {}
+}
+
+class NullNode {
+    constructor(public value: number, public next: NullNode | null) {}
+}
+
+function sumFor(head: Node | undefined) {
+    let sum: number = 0;
+    for (let node = head; node; node = node.next) {
+        sum += node.value;
+    }
+
+    return sum;
+}
+
+function sumWhile(head: Node | undefined) {
+    let sum: number = 0;
+    let node = head;
+    while (node) {
+        sum += node.value;
+        node = node.next;
+    }
+
+    return sum;
+}
+
+function sumIf(head: Node | undefined) {
+    let sum: number = 0;
+    if (head) {
+        sum += head.value;
+    }
+
+    return sum;
+}
+
+function sumForNull(head: NullNode | null) {
+    let sum: number = 0;
+    for (let node = head; node; node = node.next) {
+        sum += node.value;
+    }
+
+    return sum;
+}
+
+function countForString(s: string | undefined) {
+    let count = 0;
+    for (let t = s; t; t = undefined) {
+        count++;
+    }
+
+    return count;
+}
+
+function main() {
+    let head: Node | undefined = new Node(1, new Node(2, undefined));
+    let sum: number = 0;
+    for (let node = head; node; node = node.next) {
+        sum += node.value;
+    }
+
+    print(sum);
+    assert(sum == 3, "for over an optional class, at the call site");
+
+    assert(sumFor(head) == 3, "for over an optional class");
+    assert(sumFor(new Node(5, undefined)) == 5, "for over one node");
+    assert(sumFor(undefined) == 0, "for over undefined");
+
+    assert(sumWhile(head) == 3, "while over an optional class");
+    assert(sumWhile(undefined) == 0, "while over undefined");
+
+    assert(sumIf(head) == 1, "if on an optional class");
+    assert(sumIf(undefined) == 0, "if on undefined");
+
+    assert(sumForNull(new NullNode(4, new NullNode(6, null))) == 10, "for over a nullable class");
+    assert(sumForNull(null) == 0, "for over null");
+
+    assert(countForString("a") == 1, "for over an optional string");
+    assert(countForString(undefined) == 0, "for over undefined string");
+
+    print("done.");
+}