Merge remote-tracking branch 'origin/topic/jsiwek/gh-1483-mismatch-ctor-init-errors'

* origin/topic/jsiwek/gh-1483-mismatch-ctor-init-errors:
  GH-1483: Improve error for mismatched container initialization types

CHANGES

@@ -1,3 +1,13 @@
+
+4.1.0-dev.545 | 2021-04-26 11:14:49 -0700
+
+  * GH-1483: Improve error for mismatched container initialization types (Jon Siwek, Corelight)
+
+    For example, trying to assign a vector, table, set, or record
+    constructor expression to a global variable of a different type now
+    provides a more explanatory error message than the previous
+    "Val::CONVERTER" fatal-error and coredump.
+
 4.1.0-dev.543 | 2021-04-26 09:53:53 -0700
 
   * Update btest baselines for --enable-mobile-ipv6 builds (Tim Wojtulewicz, Corelight)

VERSION

@@ -1 +1 @@
-4.1.0-dev.543
+4.1.0-dev.545

src/Expr.cc

@@ -24,6 +24,18 @@
 
 namespace zeek::detail {
 
+static bool init_tag_check(const Expr* expr, const char* name,
+                           TypeTag expect_tag, TypeTag init_tag)
+	{
+	if ( expect_tag == init_tag )
+		return true;
+
+	auto msg = util::fmt("unexpected use of %s in '%s' initialization",
+	                     name, type_name(init_tag));
+	expr->Error(msg);
+	return false;
+	}
+
 const char* expr_name(BroExprTag t)
 	{
 	static const char* expr_names[int(NUM_EXPRS)] = {
@@ -3215,6 +3227,15 @@ RecordConstructorExpr::~RecordConstructorExpr()
 
 ValPtr RecordConstructorExpr::InitVal(const zeek::Type* t, ValPtr aggr) const
 	{
+	if ( IsError() )
+		{
+		Error("bad record initializer");
+		return nullptr;
+		}
+
+	if ( ! init_tag_check(this, "record constructor", TYPE_RECORD, t->Tag()) )
+		return nullptr;
+
 	auto v = Eval(nullptr);
 
 	if ( v )
@@ -3394,6 +3415,9 @@ ValPtr TableConstructorExpr::InitVal(const zeek::Type* t, ValPtr aggr) const
 	if ( IsError() )
 		return nullptr;
 
+	if ( ! init_tag_check(this, "table constructor", TYPE_TABLE, t->Tag()) )
+		return nullptr;
+
 	auto tt = GetType<TableType>();
 
 	auto tval = aggr ?
@@ -3508,6 +3532,9 @@ ValPtr SetConstructorExpr::InitVal(const zeek::Type* t, ValPtr aggr) const
 	if ( IsError() )
 		return nullptr;
 
+	if ( ! init_tag_check(this, "set constructor", TYPE_TABLE, t->Tag()) )
+		return nullptr;
+
 	const auto& index_type = t->AsTableType()->GetIndices();
 	auto tt = GetType<TableType>();
 	auto tval = aggr ?
@@ -3606,6 +3633,9 @@ ValPtr VectorConstructorExpr::InitVal(const zeek::Type* t, ValPtr aggr) const
 	if ( IsError() )
 		return nullptr;
 
+	if ( ! init_tag_check(this, "vector constructor", TYPE_VECTOR, t->Tag()) )
+		return nullptr;
+
 	auto vt = GetType<VectorType>();
 	auto vec = aggr ?
 	        VectorValPtr{AdoptRef{}, aggr.release()->AsVectorVal()} :
@@ -3864,6 +3894,15 @@ RecordCoerceExpr::RecordCoerceExpr(ExprPtr arg_op, RecordTypePtr r)
 
 ValPtr RecordCoerceExpr::InitVal(const zeek::Type* t, ValPtr aggr) const
 	{
+	if ( IsError() )
+		{
+		Error("bad record initializer");
+		return nullptr;
+		}
+
+	if ( ! init_tag_check(this, "record", TYPE_RECORD, t->Tag()) )
+		return nullptr;
+
 	if ( auto v = Eval(nullptr) )
 		{
 		RecordVal* rv = v->AsRecordVal();

testing/btest/Baseline/language.mismatched-container-ctor-types/.stderr

@@ -0,0 +1,11 @@
+### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
+error in <...>/mismatched-container-ctor-types.zeek, line 6: unexpected use of vector constructor in 'table' initialization (vector())
+error in <...>/mismatched-container-ctor-types.zeek, line 7: unexpected use of table constructor in 'vector' initialization (table())
+error in <...>/mismatched-container-ctor-types.zeek, line 8: unexpected use of set constructor in 'vector' initialization (set())
+error in <...>/mismatched-container-ctor-types.zeek, line 9: unexpected use of record constructor in 'vector' initialization ([])
+error in <...>/mismatched-container-ctor-types.zeek, line 10: unexpected use of record in 'vector' initialization ((coerce [] to R))
+error in <...>/mismatched-container-ctor-types.zeek, line 12: type clash in assignment (lt = vector())
+error in <...>/mismatched-container-ctor-types.zeek, line 13: type clash in assignment (lv0 = table())
+error in <...>/mismatched-container-ctor-types.zeek, line 14: type clash in assignment (lv1 = set())
+error in <...>/mismatched-container-ctor-types.zeek, line 15: type clash in assignment (lv2 = [])
+error in <...>/mismatched-container-ctor-types.zeek, line 16: type clash in assignment (lv3 = (coerce [] to R))

testing/btest/language/mismatched-container-ctor-types.zeek

@@ -0,0 +1,16 @@
+# @TEST-EXEC-FAIL: zeek -b %INPUT
+# @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff .stderr
+# @TEST-DOC: Mismatched type-constructor initializations fail with reasonable error message
+
+type R: record { a: bool &default=T; };
+global t: table[string] of vector of string = vector();
+global v0: vector of string = table();
+global v1: vector of string = set();
+global v2: vector of string = [];
+global v3: vector of string = R();
+
+local lt: table[string] of vector of string = vector();
+local lv0: vector of string = table();
+local lv1: vector of string = set();
+local lv2: vector of string = [];
+local lv3: vector of string = R();