sema: properly handle Array/Dictionary literals as compile-time literals

Author: nkcsgexi

lib/AST/Expr.cpp

@@ -199,10 +199,38 @@ Expr *Expr::getSemanticsProvidingExpr() {
 }
 
 bool Expr::isSemanticallyConstExpr() const {
-  if (auto *LE = dyn_cast<LiteralExpr>(getSemanticsProvidingExpr())) {
-    return LE->getKind() != ExprKind::InterpolatedStringLiteral;
+  auto E = getSemanticsProvidingExpr();
+  if (!E) {
+    return false;
+  }
+  switch(E->getKind()) {
+  case ExprKind::IntegerLiteral:
+  case ExprKind::NilLiteral:
+  case ExprKind::BooleanLiteral:
+  case ExprKind::FloatLiteral:
+  case ExprKind::StringLiteral:
+    return true;
+  case ExprKind::Array:
+  case ExprKind::Dictionary: {
+    auto *CE = cast<CollectionExpr>(E);
+    for (auto *EL: CE->getElements()) {
+      if (!EL->isSemanticallyConstExpr())
+        return false;
+    }
+    return true;
+  }
+  case ExprKind::Tuple: {
+    auto *TE = cast<TupleExpr>(E);
+    for (auto *EL: TE->getElements()) {
+      if (!EL->isSemanticallyConstExpr()) {
+        return false;
+      }
+    }
+    return true;
+  }
+  default:
+    return false;
   }
-  return false;
 }
 
 Expr *Expr::getValueProvidingExpr() {

test/Sema/const_pass_as_arguments.swift

@@ -3,16 +3,25 @@
 public func takeIntConst(_ a: _const Int) {}
 public func takeStringConst(_ a: _const String) {}
 public func takeDoubleConst(_ a: _const Double) {}
+public func takeArrayConst(_ a: _const [String]) {}
+public func takeDictConst(_ a: _const [Int: String]) {}
 
-func main(_ i: Int, _ d: Double, _ s: String) {
+func main(_ i: Int, _ d: Double, _ s: String, arr: [String], dict: [Int: String]) {
 	takeIntConst(2)
 	takeDoubleConst(3.3)
 	takeStringConst("")
+	takeArrayConst([""])
+	takeDictConst([1: "", 2: "text"])
 
 	takeIntConst(i) // expected-error {{expect a compile-time constant literal}}
 	takeDoubleConst(d) // expected-error {{expect a compile-time constant literal}}
 	takeStringConst("\(d)") // expected-error {{expect a compile-time constant literal}}
 	takeStringConst(s) // expected-error {{expect a compile-time constant literal}}
+	takeArrayConst(arr) // expected-error {{expect a compile-time constant literal}}
+	takeArrayConst([s]) // expected-error {{expect a compile-time constant literal}}
+	takeArrayConst(["", s]) // expected-error {{expect a compile-time constant literal}}
+	takeDictConst([1: "", 2: s]) // expected-error {{expect a compile-time constant literal}}
+	takeDictConst([1: "", i: "text"]) // expected-error {{expect a compile-time constant literal}}
 }
 
 public struct Utils {