diff --git a/.editorconfig b/.editorconfig
index d80fb3570..829878823 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -14,7 +14,7 @@ indent_size = 4
 indent_style = space
 indent_size = 4
 
-[std/**.sol]
+[*.sol]
 indent_style = space
 indent_size = 4
 
diff --git a/scripts/error_codes.py b/scripts/error_codes.py
index 1520b5f4e..9ecfd0dca 100755
--- a/scripts/error_codes.py
+++ b/scripts/error_codes.py
@@ -220,16 +220,17 @@ def examine_id_coverage(top_dir, source_id_to_file_names, new_ids_only=False):
             return False
 
     old_source_only_ids = {
-        "1123", "1133", "1218", "1220", "1584", "1823", "1950",
-        "1988", "2418", "2461", "2512", "2592", "2657", "2800", "2842", "2856",
+        "1123", "1218", "1220", "1584", "1823", "1950",
+        "1988", "2461", "2512", "2592", "2657", "2800", "2842", "2856",
         "3046", "3263", "3356", "3441", "3682", "3876",
-        "3893", "3996", "4010", "4281", "4802", "4805", "4828",
-        "4904", "4990", "5052", "5073", "5170", "5188", "5272", "5347", "5473",
-        "5622", "6041", "6052", "6084", "6272", "6708", "6792", "6931", "7110", "7128", "7186",
+        "3893", "3996", "4010", "4281", "4802",
+        "5052", "5073", "5170", "5188", "5272", "5347", "5473",
+        "5622", "6041", "6084", "6272", "7110", "7128", "7186",
         "7589", "7593", "7653", "7812", "7885", "8065", "8084", "8140",
         "8261", "8312", "8592", "8758", "9011",
-        "9085", "9390", "9440", "9547", "9551", "9615", "9980"
+        "9085", "9390", "9440", "9547", "9551", "9615", "9980",
     }
+
     new_source_only_ids = source_only_ids - old_source_only_ids
     if len(new_source_only_ids) != 0:
         print("The following new error code(s), not covered by tests, found:")
diff --git a/test/libsolidity/InlineAssembly.cpp b/test/libsolidity/InlineAssembly.cpp
index 1d61484a9..d6f7becf0 100644
--- a/test/libsolidity/InlineAssembly.cpp
+++ b/test/libsolidity/InlineAssembly.cpp
@@ -170,343 +170,7 @@ do { successParse((text), false, false, AssemblyStack::Language::StrictAssembly)
 
 BOOST_AUTO_TEST_SUITE(SolidityInlineAssembly)
 
-
-BOOST_AUTO_TEST_SUITE(Parsing)
-
-BOOST_AUTO_TEST_CASE(smoke_test)
-{
-	BOOST_CHECK(successParse("{ }"));
-}
-
-BOOST_AUTO_TEST_CASE(surplus_input)
-{
-	CHECK_PARSE_ERROR("{ } { }", ParserError, "Expected end of source but got '{'");
-}
-
-BOOST_AUTO_TEST_CASE(simple_instructions)
-{
-	BOOST_CHECK(successParse("{ let y := mul(0x10, mul(0x20, mload(0x40)))}"));
-}
-
-BOOST_AUTO_TEST_CASE(selfdestruct)
-{
-	BOOST_CHECK(successParse("{ selfdestruct(0x02) }"));
-}
-
-BOOST_AUTO_TEST_CASE(keywords)
-{
-	BOOST_CHECK(successParse("{ return (byte(1, 2), 2) pop(address()) }"));
-}
-
-BOOST_AUTO_TEST_CASE(constants)
-{
-	BOOST_CHECK(successParse("{ pop(mul(7, 8)) }"));
-}
-
-BOOST_AUTO_TEST_CASE(vardecl)
-{
-	BOOST_CHECK(successParse("{ let x := 7 }"));
-}
-
-BOOST_AUTO_TEST_CASE(vardecl_name_clashes)
-{
-	CHECK_PARSE_ERROR("{ let x := 1 let x := 2 }", DeclarationError, "Variable name x already taken in this scope.");
-}
-
-BOOST_AUTO_TEST_CASE(vardecl_multi)
-{
-	BOOST_CHECK(successParse("{ function f() -> x, y {} let x, y := f() }"));
-}
-
-BOOST_AUTO_TEST_CASE(vardecl_multi_conflict)
-{
-	CHECK_PARSE_ERROR("{ function f() -> x, y {} let x, x := f() }", DeclarationError, "Variable name x already taken in this scope.");
-}
-
-BOOST_AUTO_TEST_CASE(vardecl_bool)
-{
-	successParse("{ let x := true }");
-	successParse("{ let x := false }");
-}
-
-BOOST_AUTO_TEST_CASE(vardecl_empty)
-{
-	BOOST_CHECK(successParse("{ let x }"));
-}
-
-BOOST_AUTO_TEST_CASE(functional)
-{
-	BOOST_CHECK(successParse("{ let x := 2 x := add(add(7, mul(6, x)), mul(7, 8)) }"));
-}
-
-BOOST_AUTO_TEST_CASE(functional_partial)
-{
-	CHECK_PARSE_ERROR("{ let x := byte }", ParserError, "Expected '(' but got '}'");
-}
-
-BOOST_AUTO_TEST_CASE(functional_partial_success)
-{
-	BOOST_CHECK(successParse("{ let x := byte(1, 2) }"));
-}
-
-BOOST_AUTO_TEST_CASE(functional_assignment)
-{
-	BOOST_CHECK(successParse("{ let x := 2 x := 7 }"));
-}
-
-BOOST_AUTO_TEST_CASE(functional_assignment_complex)
-{
-	BOOST_CHECK(successParse("{ let x := 2 x := add(add(7, mul(6, x)), mul(7, 8)) }"));
-}
-
-BOOST_AUTO_TEST_CASE(vardecl_complex)
-{
-	BOOST_CHECK(successParse("{ let y := 2 let x := add(add(7, mul(6, y)), mul(7, 8)) }"));
-}
-
-BOOST_AUTO_TEST_CASE(variable_use_before_decl)
-{
-	CHECK_PARSE_ERROR("{ x := 2 let x := 3 }", DeclarationError, "Variable x used before it was declared.");
-	CHECK_PARSE_ERROR("{ let x := mul(2, x) }", DeclarationError, "Variable x used before it was declared.");
-}
-
-BOOST_AUTO_TEST_CASE(if_statement)
-{
-	BOOST_CHECK(successParse("{ if 42 {} }"));
-	BOOST_CHECK(successParse("{ if 42 { let x := 3 } }"));
-	BOOST_CHECK(successParse("{ function f() -> x {} if f() { pop(f()) } }"));
-}
-
-BOOST_AUTO_TEST_CASE(if_statement_scope)
-{
-	BOOST_CHECK(successParse("{ let x := 2 if 42 { x := 3 } }"));
-	CHECK_PARSE_ERROR("{ if 32 { let x := 3 } x := 2 }", DeclarationError, "Variable not found or variable not lvalue.");
-}
-
-BOOST_AUTO_TEST_CASE(if_statement_invalid)
-{
-	CHECK_PARSE_ERROR("{ if mload {} }", ParserError, "Expected '(' but got '{'");
-	BOOST_CHECK("{ if calldatasize() {}");
-	CHECK_PARSE_ERROR("{ if mstore(1, 1) {} }", TypeError, "Expected expression to evaluate to one value, but got 0 values instead.");
-	CHECK_PARSE_ERROR("{ if 32 let x := 3 }", ParserError, "Expected '{' but got reserved keyword 'let'");
-}
-
-BOOST_AUTO_TEST_CASE(switch_statement)
-{
-	BOOST_CHECK(successParse("{ switch 42 default {} }"));
-	BOOST_CHECK(successParse("{ switch 42 case 1 {} }"));
-	BOOST_CHECK(successParse("{ switch 42 case 1 {} case 2 {} }"));
-	BOOST_CHECK(successParse("{ switch 42 case 1 {} default {} }"));
-	BOOST_CHECK(successParse("{ switch 42 case 1 {} case 2 {} default {} }"));
-	BOOST_CHECK(successParse("{ switch mul(1, 2) case 1 {} case 2 {} default {} }"));
-	BOOST_CHECK(successParse("{ function f() -> x {} switch f() case 1 {} case 2 {} default {} }"));
-}
-
-BOOST_AUTO_TEST_CASE(switch_no_cases)
-{
-	CHECK_PARSE_ERROR("{ switch 42 }", ParserError, "Switch statement without any cases.");
-}
-
-BOOST_AUTO_TEST_CASE(switch_duplicate_case)
-{
-	CHECK_PARSE_ERROR("{ switch 42 case 1 {} case 1 {} default {} }", DeclarationError, "Duplicate case defined.");
-}
-
-BOOST_AUTO_TEST_CASE(switch_invalid_expression)
-{
-	CHECK_PARSE_ERROR("{ switch {} case 1 {} default {} }", ParserError, "Literal or identifier expected.");
-	CHECK_PARSE_ERROR(
-		"{ switch mload case 1 {} default {} }",
-		ParserError,
-		"Expected '(' but got reserved keyword 'case'"
-	);
-	CHECK_PARSE_ERROR(
-		"{ switch mstore(1, 1) case 1 {} default {} }",
-		TypeError,
-		"Expected expression to evaluate to one value, but got 0 values instead."
-	);
-}
-
-BOOST_AUTO_TEST_CASE(switch_default_before_case)
-{
-	CHECK_PARSE_ERROR("{ switch 42 default {} case 1 {} }", ParserError, "Case not allowed after default case.");
-}
-
-BOOST_AUTO_TEST_CASE(switch_duplicate_default_case)
-{
-	CHECK_PARSE_ERROR("{ switch 42 default {} default {} }", ParserError, "Only one default case allowed.");
-}
-
-BOOST_AUTO_TEST_CASE(switch_invalid_case)
-{
-	CHECK_PARSE_ERROR("{ switch 42 case mul(1, 2) {} case 2 {} default {} }", ParserError, "Literal expected.");
-}
-
-BOOST_AUTO_TEST_CASE(switch_invalid_body)
-{
-	CHECK_PARSE_ERROR("{ switch 42 case 1 mul case 2 {} default {} }", ParserError, "Expected '{' but got identifier");
-}
-
-BOOST_AUTO_TEST_CASE(for_statement)
-{
-	BOOST_CHECK(successParse("{ for {} 1 {} {} }"));
-	BOOST_CHECK(successParse("{ for { let i := 1 } lt(i, 5) { i := add(i, 1) } {} }"));
-}
-
-BOOST_AUTO_TEST_CASE(for_invalid_expression)
-{
-	CHECK_PARSE_ERROR("{ for {} {} {} {} }", ParserError, "Literal or identifier expected.");
-	CHECK_PARSE_ERROR("{ for 1 1 {} {} }", ParserError, "Expected '{' but got 'Number'");
-	CHECK_PARSE_ERROR("{ for {} 1 1 {} }", ParserError, "Expected '{' but got 'Number'");
-	CHECK_PARSE_ERROR("{ for {} 1 {} 1 }", ParserError, "Expected '{' but got 'Number'");
-	CHECK_PARSE_ERROR("{ for {} mload {} {} }", ParserError, "Expected '(' but got '{'");
-	CHECK_PARSE_ERROR("{ for {} mstore(1, 1) {} {} }", TypeError, "Expected expression to evaluate to one value, but got 0 values instead.");
-}
-
-BOOST_AUTO_TEST_CASE(for_visibility)
-{
-	BOOST_CHECK(successParse("{ for { let i := 1 } i { pop(i) } { pop(i) } }"));
-	CHECK_PARSE_ERROR("{ for {} i { let i := 1 } {} }", DeclarationError, "Identifier not found");
-	CHECK_PARSE_ERROR("{ for {} 1 { let i := 1 } { pop(i) } }", DeclarationError, "Identifier not found");
-	CHECK_PARSE_ERROR("{ for {} 1 { pop(i) } { let i := 1 } }", DeclarationError, "Identifier not found");
-	CHECK_PARSE_ERROR("{ for { pop(i) } 1 { let i := 1 } {} }", DeclarationError, "Identifier not found");
-	CHECK_PARSE_ERROR("{ for { pop(i) } 1 { } { let i := 1 } }", DeclarationError, "Identifier not found");
-	CHECK_PARSE_ERROR("{ for {} i {} { let i := 1 } }", DeclarationError, "Identifier not found");
-	CHECK_PARSE_ERROR("{ for {} 1 { pop(i) } { let i := 1 } }", DeclarationError, "Identifier not found");
-	CHECK_PARSE_ERROR("{ for { let x := 1 } 1 { let x := 1 } {} }", DeclarationError, "Variable name x already taken in this scope");
-	CHECK_PARSE_ERROR("{ for { let x := 1 } 1 {} { let x := 1 } }", DeclarationError, "Variable name x already taken in this scope");
-	CHECK_PARSE_ERROR("{ let x := 1 for { let x := 1 } 1 {} {} }", DeclarationError, "Variable name x already taken in this scope");
-	CHECK_PARSE_ERROR("{ let x := 1 for {} 1 { let x := 1 } {} }", DeclarationError, "Variable name x already taken in this scope");
-	CHECK_PARSE_ERROR("{ let x := 1 for {} 1 {} { let x := 1 } }", DeclarationError, "Variable name x already taken in this scope");
-	// Check that body and post are not sub-scopes of each other.
-	BOOST_CHECK(successParse("{ for {} 1 { let x := 1 } { let x := 1 } }"));
-}
-
-BOOST_AUTO_TEST_CASE(blocks)
-{
-	BOOST_CHECK(successParse("{ let x := 7 { let y := 3 } { let z := 2 } }"));
-}
-
-BOOST_AUTO_TEST_CASE(number_literals)
-{
-	BOOST_CHECK(successParse("{ let x := 1 }"));
-	CHECK_PARSE_ERROR("{ let x := .1 }", ParserError, "Invalid number literal.");
-	CHECK_PARSE_ERROR("{ let x := 1e5 }", ParserError, "Invalid number literal.");
-	CHECK_PARSE_ERROR("{ let x := 67.235 }", ParserError, "Invalid number literal.");
-	CHECK_STRICT_ERROR("{ let x := 0x1ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff }", TypeError, "Number literal too large (> 256 bits)");
-}
-
-BOOST_AUTO_TEST_CASE(function_definitions)
-{
-	BOOST_CHECK(successParse("{ function f() { } function g(a) -> x { } }"));
-}
-
-BOOST_AUTO_TEST_CASE(function_definitions_multiple_args)
-{
-	BOOST_CHECK(successParse("{ function f(a, d) { } function g(a, d) -> x, y { } }"));
-}
-
-BOOST_AUTO_TEST_CASE(function_calls)
-{
-	BOOST_CHECK(successParse("{ function f(a) -> b {} function g(a, b, c) {} function x() { g(1, 2, f(mul(2, 3))) x() } }"));
-}
-
-BOOST_AUTO_TEST_CASE(opcode_for_functions)
-{
-	CHECK_PARSE_ERROR("{ function gas() { } }", ParserError, "Cannot use builtin");
-}
-
-BOOST_AUTO_TEST_CASE(opcode_for_function_args)
-{
-	CHECK_PARSE_ERROR("{ function f(gas) { } }", ParserError, "Cannot use builtin");
-	CHECK_PARSE_ERROR("{ function f() -> gas { } }", ParserError, "Cannot use builtin");
-}
-
-BOOST_AUTO_TEST_CASE(name_clashes)
-{
-	CHECK_PARSE_ERROR("{ let g := 2 function g() { } }", DeclarationError, "Variable name g already taken in this scope");
-}
-
-BOOST_AUTO_TEST_CASE(name_clashes_function_subscope)
-{
-	CHECK_PARSE_ERROR("{ function g() { function g() {} } }", DeclarationError, "Function name g already taken in this scope");
-}
-
-BOOST_AUTO_TEST_CASE(name_clashes_function_subscope_reverse)
-{
-	CHECK_PARSE_ERROR("{ { function g() {} } function g() { } }", DeclarationError, "Function name g already taken in this scope");
-}
-
-BOOST_AUTO_TEST_CASE(name_clashes_function_variable_subscope)
-{
-	CHECK_PARSE_ERROR("{ function g() { let g := 0 } }", DeclarationError, "Variable name g already taken in this scope");
-}
-
-BOOST_AUTO_TEST_CASE(name_clashes_function_variable_subscope_reverse)
-{
-	CHECK_PARSE_ERROR("{ { let g := 0 } function g() { } }", DeclarationError, "Variable name g already taken in this scope");
-}
-BOOST_AUTO_TEST_CASE(functions_in_parallel_scopes)
-{
-	BOOST_CHECK(successParse("{ { function g() {} } { function g() {} } }"));
-}
-
-BOOST_AUTO_TEST_CASE(variable_access_cross_functions)
-{
-	CHECK_PARSE_ERROR("{ let x := 2 function g() { pop(x) } }", DeclarationError, "Identifier not found.");
-}
-
-BOOST_AUTO_TEST_CASE(invalid_tuple_assignment)
-{
-	CHECK_PARSE_ERROR("{ let x, y := 1 }", DeclarationError, "Variable count mismatch: 2 variables and 1 values");
-}
-
-BOOST_AUTO_TEST_CASE(instruction_too_few_arguments)
-{
-	CHECK_PARSE_ERROR("{ pop(mul()) }", TypeError, "Function expects 2 arguments but got 0.");
-	CHECK_PARSE_ERROR("{ pop(mul(1)) }", TypeError, "Function expects 2 arguments but got 1.");
-}
-
-BOOST_AUTO_TEST_CASE(instruction_too_many_arguments)
-{
-	CHECK_PARSE_ERROR("{ pop(mul(1, 2, 3)) }", TypeError, "Function expects 2 arguments but got 3");
-}
-
-BOOST_AUTO_TEST_CASE(recursion_depth)
-{
-	string input;
-	for (size_t i = 0; i < 20000; i++)
-		input += "{";
-	input += "let x := 0";
-	for (size_t i = 0; i < 20000; i++)
-		input += "}";
-
-	CHECK_PARSE_ERROR(input, ParserError, "recursion");
-}
-
-BOOST_AUTO_TEST_CASE(multiple_assignment)
-{
-	CHECK_PARSE_ERROR("{ let x function f() -> a, b {} 123, x := f() }", ParserError, "Variable name must precede \",\" in multiple assignment.");
-	CHECK_PARSE_ERROR("{ let x function f() -> a, b {} x, 123 := f() }", ParserError, "Variable name must precede \":=\" in assignment.");
-
-	/// NOTE: Travis hiccups if not having a variable
-	char const* text = R"(
-	{
-		function f(a) -> r1, r2 {
-			r1 := a
-			r2 := 7
-		}
-		let x := 9
-		let y := 2
-		x, y := f(x)
-	}
-	)";
-	BOOST_CHECK(successParse(text));
-}
-
-BOOST_AUTO_TEST_SUITE_END()
-
-BOOST_AUTO_TEST_SUITE(Printing)
+BOOST_AUTO_TEST_SUITE(Printing) // {{{
 
 BOOST_AUTO_TEST_CASE(print_smoke)
 {
@@ -593,8 +257,9 @@ BOOST_AUTO_TEST_CASE(function_calls)
 }
 
 BOOST_AUTO_TEST_SUITE_END()
+// }}}
 
-BOOST_AUTO_TEST_SUITE(Analysis)
+BOOST_AUTO_TEST_SUITE(Analysis) // {{{
 
 BOOST_AUTO_TEST_CASE(string_literals)
 {
@@ -633,50 +298,6 @@ BOOST_AUTO_TEST_CASE(revert)
 	BOOST_CHECK(successAssemble("{ revert(0, 0) }"));
 }
 
-BOOST_AUTO_TEST_CASE(function_calls)
-{
-	BOOST_CHECK(successAssemble("{ function f() {} }"));
-	BOOST_CHECK(successAssemble("{ function f() { let y := 2 } }"));
-	BOOST_CHECK(successAssemble("{ function f() -> z { let y := 2 } }"));
-	BOOST_CHECK(successAssemble("{ function f(a) { let y := 2 } }"));
-	BOOST_CHECK(successAssemble("{ function f(a) { let y := a } }"));
-	BOOST_CHECK(successAssemble("{ function f() -> x, y, z {} }"));
-	BOOST_CHECK(successAssemble("{ function f(x, y, z) {} }"));
-	BOOST_CHECK(successAssemble("{ function f(a, b) -> x, y, z { y := a } }"));
-	BOOST_CHECK(successAssemble("{ function f() {} f() }"));
-	BOOST_CHECK(successAssemble("{ function f() -> x, y { x := 1 y := 2} let a, b := f() }"));
-	BOOST_CHECK(successAssemble("{ function f(a, b) -> x, y { x := b y := a } let a, b := f(2, 3) }"));
-	BOOST_CHECK(successAssemble("{ function rec(a) { rec(sub(a, 1)) } rec(2) }"));
-	BOOST_CHECK(successAssemble("{ let r := 2 function f() -> x, y { x := 1 y := 2} let a, b := f() b := r }"));
-	BOOST_CHECK(successAssemble("{ function f() { g() } function g() { f() } }"));
-}
-
-BOOST_AUTO_TEST_CASE(embedded_functions)
-{
-	BOOST_CHECK(successAssemble("{ function f(r, s) -> x { function g(a) -> b { } x := g(2) } let x := f(2, 3) }"));
-}
-
-BOOST_AUTO_TEST_CASE(switch_statement)
-{
-	BOOST_CHECK(successAssemble("{ switch 1 default {} }"));
-	BOOST_CHECK(successAssemble("{ switch 1 case 1 {} default {} }"));
-	BOOST_CHECK(successAssemble("{ switch 1 case 1 {} }"));
-	BOOST_CHECK(successAssemble("{ let a := 3 switch a case 1 { a := 1 } case 2 { a := 5 } a := 9}"));
-	BOOST_CHECK(successAssemble("{ let a := 2 switch calldataload(0) case 1 { a := 1 } case 2 { a := 5 } }"));
-}
-
-BOOST_AUTO_TEST_CASE(for_statement)
-{
-	BOOST_CHECK(successAssemble("{ for {} 1 {} {} }"));
-	BOOST_CHECK(successAssemble("{ let x := calldatasize() for { let i := 0} lt(i, x) { i := add(i, 1) } { mstore(i, 2) } }"));
-}
-
-BOOST_AUTO_TEST_CASE(if_statement)
-{
-	BOOST_CHECK(successAssemble("{ if 1 {} }"));
-	BOOST_CHECK(successAssemble("{ let x := 0 if eq(calldatasize(), 0) { x := 1 } mstore(0, x) }"));
-}
-
 BOOST_AUTO_TEST_CASE(large_constant)
 {
 	auto source = R"({
@@ -706,13 +327,6 @@ BOOST_AUTO_TEST_CASE(returndatacopy)
 	BOOST_CHECK(successAssemble("{ returndatacopy(0, 32, 64) }"));
 }
 
-BOOST_AUTO_TEST_CASE(returndatacopy_functional)
-{
-	if (!solidity::test::CommonOptions::get().evmVersion().supportsReturndata())
-		return;
-	BOOST_CHECK(successAssemble("{ returndatacopy(0, 32, 64) }"));
-}
-
 BOOST_AUTO_TEST_CASE(staticcall)
 {
 	if (!solidity::test::CommonOptions::get().evmVersion().hasStaticCall())
@@ -751,7 +365,7 @@ BOOST_AUTO_TEST_CASE(jump_error)
 	CHECK_PARSE_WARNING("{ jumpi(44, 2) }", DeclarationError, "Function not found.");
 }
 
-BOOST_AUTO_TEST_SUITE_END()
+BOOST_AUTO_TEST_SUITE_END() // }}}
 
 BOOST_AUTO_TEST_SUITE_END()
 
diff --git a/test/libyul/yulSyntaxTests/constants.yul b/test/libyul/yulSyntaxTests/constants.yul
new file mode 100644
index 000000000..b1713aeea
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/constants.yul
@@ -0,0 +1,3 @@
+{
+	pop(mul(7, 8))
+}
diff --git a/test/libyul/yulSyntaxTests/for_expr_invalid_1.yul b/test/libyul/yulSyntaxTests/for_expr_invalid_1.yul
new file mode 100644
index 000000000..00f0a4d58
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_expr_invalid_1.yul
@@ -0,0 +1,5 @@
+{
+	for {} {} {} {}
+}
+// ----
+// ParserError 1856: (10-11): Literal or identifier expected.
diff --git a/test/libyul/yulSyntaxTests/for_expr_invalid_2.yul b/test/libyul/yulSyntaxTests/for_expr_invalid_2.yul
new file mode 100644
index 000000000..d4d801204
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_expr_invalid_2.yul
@@ -0,0 +1,5 @@
+{
+	for 1 1 {} {}
+}
+// ----
+// ParserError 2314: (7-8): Expected '{' but got 'Number'
diff --git a/test/libyul/yulSyntaxTests/for_expr_invalid_3.yul b/test/libyul/yulSyntaxTests/for_expr_invalid_3.yul
new file mode 100644
index 000000000..8f8268659
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_expr_invalid_3.yul
@@ -0,0 +1,5 @@
+{
+	for {} 1 1 {}
+}
+// ----
+// ParserError 2314: (12-13): Expected '{' but got 'Number'
diff --git a/test/libyul/yulSyntaxTests/for_expr_invalid_4.yul b/test/libyul/yulSyntaxTests/for_expr_invalid_4.yul
new file mode 100644
index 000000000..abd2260d7
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_expr_invalid_4.yul
@@ -0,0 +1,5 @@
+{
+	for {} 1 {} 1
+}
+// ----
+// ParserError 2314: (15-16): Expected '{' but got 'Number'
diff --git a/test/libyul/yulSyntaxTests/for_expr_invalid_5.yul b/test/libyul/yulSyntaxTests/for_expr_invalid_5.yul
new file mode 100644
index 000000000..acf9be847
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_expr_invalid_5.yul
@@ -0,0 +1,5 @@
+{
+	for {} mload {} {}
+}
+// ----
+// ParserError 2314: (16-17): Expected '(' but got '{'
diff --git a/test/libyul/yulSyntaxTests/for_expr_invalid_6.yul b/test/libyul/yulSyntaxTests/for_expr_invalid_6.yul
new file mode 100644
index 000000000..42883052e
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_expr_invalid_6.yul
@@ -0,0 +1,7 @@
+{
+	for {} mstore(1, 1) {} {}
+}
+// ====
+// dialect: evm
+// ----
+// TypeError 3950: (10-22): Expected expression to evaluate to one value, but got 0 values instead.
diff --git a/test/libyul/yulSyntaxTests/for_statement_2.yul b/test/libyul/yulSyntaxTests/for_statement_2.yul
new file mode 100644
index 000000000..1c74f4239
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_statement_2.yul
@@ -0,0 +1,10 @@
+{
+
+	{ for {} 1 {} {} }
+	{ for { let i := 1 } lt(i, 5) { i := add(i, 1) } {} }
+	{ for {} 1 {} {} }
+	{ let x := calldatasize() for { let i := 0} lt(i, x) { i := add(i, 1) } { mstore(i, 2) } }
+}
+// ====
+// dialect: evm
+// ----
diff --git a/test/libyul/yulSyntaxTests/for_visibility_1.yul b/test/libyul/yulSyntaxTests/for_visibility_1.yul
new file mode 100644
index 000000000..05d876335
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_1.yul
@@ -0,0 +1,5 @@
+{
+	for { let i := 1 } i { pop(i) } { pop(i) }
+}
+// ====
+// dialect: evm
diff --git a/test/libyul/yulSyntaxTests/for_visibility_2.yul b/test/libyul/yulSyntaxTests/for_visibility_2.yul
new file mode 100644
index 000000000..62cc90c0c
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_2.yul
@@ -0,0 +1,7 @@
+{
+	for {} i { let i := 1 } {}
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 8198: (10-11): Identifier not found.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_3.yul b/test/libyul/yulSyntaxTests/for_visibility_3.yul
new file mode 100644
index 000000000..54af2f854
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_3.yul
@@ -0,0 +1,7 @@
+{
+	for {} 1 { let i := 1 } { pop(i) }
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 8198: (33-34): Identifier not found.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_4.yul b/test/libyul/yulSyntaxTests/for_visibility_4.yul
new file mode 100644
index 000000000..68e81f3b4
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_4.yul
@@ -0,0 +1,7 @@
+{
+	for {} 1 { pop(i) } { let i := 1 }
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 8198: (18-19): Identifier not found.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_5.yul b/test/libyul/yulSyntaxTests/for_visibility_5.yul
new file mode 100644
index 000000000..2785394d8
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_5.yul
@@ -0,0 +1,7 @@
+{
+	for { pop(i) } 1 { let i := 1 } {}
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 8198: (13-14): Identifier not found.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_6.yul b/test/libyul/yulSyntaxTests/for_visibility_6.yul
new file mode 100644
index 000000000..75cb6d531
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_6.yul
@@ -0,0 +1,7 @@
+{
+	for { pop(i) } 1 { } { let i := 1 }
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 8198: (13-14): Identifier not found.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_7.yul b/test/libyul/yulSyntaxTests/for_visibility_7.yul
new file mode 100644
index 000000000..00e289714
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_7.yul
@@ -0,0 +1,7 @@
+{
+	for {} i {} { let i := 1 }
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 8198: (10-11): Identifier not found.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_8.yul b/test/libyul/yulSyntaxTests/for_visibility_8.yul
new file mode 100644
index 000000000..68e81f3b4
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_8.yul
@@ -0,0 +1,7 @@
+{
+	for {} 1 { pop(i) } { let i := 1 }
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 8198: (18-19): Identifier not found.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_9.yul b/test/libyul/yulSyntaxTests/for_visibility_9.yul
new file mode 100644
index 000000000..4cda1b165
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_9.yul
@@ -0,0 +1,7 @@
+{
+	for { let x := 1 } 1 { let x := 1 } {}
+}
+// ====
+// dialect: yul
+// ----
+// DeclarationError 1395: (26-36): Variable name x already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_A.yul b/test/libyul/yulSyntaxTests/for_visibility_A.yul
new file mode 100644
index 000000000..a5761f52a
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_A.yul
@@ -0,0 +1,7 @@
+{
+	for { let x := 1 } 1 {} { let x := 1 }
+}
+// ====
+// dialect: yul
+// ----
+// DeclarationError 1395: (29-39): Variable name x already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_B.yul b/test/libyul/yulSyntaxTests/for_visibility_B.yul
new file mode 100644
index 000000000..d315a611d
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_B.yul
@@ -0,0 +1,5 @@
+{
+	let x := 1 for { let x := 1 } 1 {} {}
+}
+// ----
+// DeclarationError 1395: (20-30): Variable name x already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_C.yul b/test/libyul/yulSyntaxTests/for_visibility_C.yul
new file mode 100644
index 000000000..81741fe7b
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_C.yul
@@ -0,0 +1,5 @@
+{
+	let x := 1 for {} 1 { let x := 1 } {}
+}
+// ----
+// DeclarationError 1395: (25-35): Variable name x already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_D.yul b/test/libyul/yulSyntaxTests/for_visibility_D.yul
new file mode 100644
index 000000000..409b10399
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_D.yul
@@ -0,0 +1,5 @@
+{
+	let x := 1 for {} 1 {} { let x := 1 }
+}
+// ----
+// DeclarationError 1395: (28-38): Variable name x already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/for_visibility_E.yul b/test/libyul/yulSyntaxTests/for_visibility_E.yul
new file mode 100644
index 000000000..1f09cd34a
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/for_visibility_E.yul
@@ -0,0 +1,6 @@
+{
+	// Check that body and post are not sub-scopes of each other.
+	for {} 1 { let x := 1 } { let x := 1 }
+}
+// ====
+// dialect: evm
diff --git a/test/libyul/yulSyntaxTests/function_calls_2.yul b/test/libyul/yulSyntaxTests/function_calls_2.yul
new file mode 100644
index 000000000..d50c27a72
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/function_calls_2.yul
@@ -0,0 +1,17 @@
+{
+	{ function f() {} }
+	{ function f() { let y := 2 } }
+	{ function f() -> z { let y := 2 } }
+	{ function f(a) { let y := 2 } }
+	{ function f(a) { let y := a } }
+	{ function f() -> x, y, z {} }
+	{ function f(x, y, z) {} }
+	{ function f(a, b) -> x, y, z { y := a } }
+	{ function f() {} f() }
+	{ function f() -> x, y { x := 1 y := 2} let a, b := f() }
+	{ function f(a, b) -> x, y { x := b y := a } let a, b := f(2, 3) }
+	{ function rec(a) { rec(sub(a, 1)) } rec(2) }
+	{ let r := 2 function f() -> x, y { x := 1 y := 2} let a, b := f() b := r }
+	{ function f() { g() } function g() { f() } }
+	{ function f(a) -> b {} function g(a, b, c) {} function x() { g(1, 2, f(mul(2, 3))) x() } }
+}
diff --git a/test/libyul/yulSyntaxTests/function_def_multiple_args.yul b/test/libyul/yulSyntaxTests/function_def_multiple_args.yul
new file mode 100644
index 000000000..5d526559f
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/function_def_multiple_args.yul
@@ -0,0 +1,4 @@
+{
+    function f(a, d) { }
+    function g(a, d) -> x, y { }
+}
diff --git a/test/libyul/yulSyntaxTests/function_definition.yul b/test/libyul/yulSyntaxTests/function_definition.yul
index 9cd21193e..1323e7620 100644
--- a/test/libyul/yulSyntaxTests/function_definition.yul
+++ b/test/libyul/yulSyntaxTests/function_definition.yul
@@ -1,4 +1,7 @@
 {
     function f (a, b  , c ) ->    y,x,z {
     }
-}
\ No newline at end of file
+
+	function g() { }
+	function h(a) -> x { }
+}
diff --git a/test/libyul/yulSyntaxTests/function_embedded.yul b/test/libyul/yulSyntaxTests/function_embedded.yul
new file mode 100644
index 000000000..e836da2b4
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/function_embedded.yul
@@ -0,0 +1,7 @@
+{
+	function f(r, s) -> x {
+		function g(a) -> b { }
+		x := g(2)
+	}
+	let x := f(2, 3)
+}
diff --git a/test/libyul/yulSyntaxTests/functional.yul b/test/libyul/yulSyntaxTests/functional.yul
new file mode 100644
index 000000000..1dbbe0199
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/functional.yul
@@ -0,0 +1,3 @@
+{
+    let x := 2 x := add(add(7, mul(6, x)), mul(7, 8))
+}
diff --git a/test/libyul/yulSyntaxTests/functional_assign_complex.yul b/test/libyul/yulSyntaxTests/functional_assign_complex.yul
new file mode 100644
index 000000000..1dbbe0199
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/functional_assign_complex.yul
@@ -0,0 +1,3 @@
+{
+    let x := 2 x := add(add(7, mul(6, x)), mul(7, 8))
+}
diff --git a/test/libyul/yulSyntaxTests/functional_assignment.yul b/test/libyul/yulSyntaxTests/functional_assignment.yul
new file mode 100644
index 000000000..7d2e6624a
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/functional_assignment.yul
@@ -0,0 +1,5 @@
+{
+    let x := 2
+    x := 7
+}
+
diff --git a/test/libyul/yulSyntaxTests/functional_partial.yul b/test/libyul/yulSyntaxTests/functional_partial.yul
new file mode 100644
index 000000000..f66225658
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/functional_partial.yul
@@ -0,0 +1,5 @@
+{
+    let x := byte
+}
+// ----
+// ParserError 2314: (20-21): Expected '(' but got '}'
diff --git a/test/libyul/yulSyntaxTests/functional_partial_success.yul b/test/libyul/yulSyntaxTests/functional_partial_success.yul
new file mode 100644
index 000000000..177407aef
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/functional_partial_success.yul
@@ -0,0 +1,3 @@
+{
+	let x := byte(1, 2)
+}
diff --git a/test/libyul/yulSyntaxTests/functional_returndatacopy.yul b/test/libyul/yulSyntaxTests/functional_returndatacopy.yul
new file mode 100644
index 000000000..84f65b09d
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/functional_returndatacopy.yul
@@ -0,0 +1,5 @@
+{
+    returndatacopy(0, 32, 64)
+}
+// ====
+// EVMVersion: >=byzantium
diff --git a/test/libyul/yulSyntaxTests/functions_in_parallel_scopes.yul b/test/libyul/yulSyntaxTests/functions_in_parallel_scopes.yul
new file mode 100644
index 000000000..05f3a2861
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/functions_in_parallel_scopes.yul
@@ -0,0 +1,4 @@
+{
+    { function g() {} }
+    { function g() {} }
+}
diff --git a/test/libyul/yulSyntaxTests/if_statement.yul b/test/libyul/yulSyntaxTests/if_statement.yul
new file mode 100644
index 000000000..6865a1b42
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/if_statement.yul
@@ -0,0 +1,8 @@
+{
+    { if 42 {} }
+    { if 42 { let x := 3 } }
+    { function f() -> x {} if f() { pop(f()) } }
+    { let x := 0 if eq(calldatasize(), 0) { x := 1 } mstore(0, x) }
+}
+// ====
+// dialect: evm
diff --git a/test/libyul/yulSyntaxTests/if_statement_invalid_1.yul b/test/libyul/yulSyntaxTests/if_statement_invalid_1.yul
new file mode 100644
index 000000000..5f73fcf2a
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/if_statement_invalid_1.yul
@@ -0,0 +1,5 @@
+{
+    if mload {}
+}
+// ----
+// ParserError 2314: (15-16): Expected '(' but got '{'
diff --git a/test/libyul/yulSyntaxTests/if_statement_invalid_2.yul b/test/libyul/yulSyntaxTests/if_statement_invalid_2.yul
new file mode 100644
index 000000000..4e7970490
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/if_statement_invalid_2.yul
@@ -0,0 +1,7 @@
+{
+	if mstore(1, 1) {}
+}
+// ====
+// dialect: evm
+// ----
+// TypeError 3950: (6-18): Expected expression to evaluate to one value, but got 0 values instead.
diff --git a/test/libyul/yulSyntaxTests/if_statement_invalid_3.yul b/test/libyul/yulSyntaxTests/if_statement_invalid_3.yul
new file mode 100644
index 000000000..fa396456f
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/if_statement_invalid_3.yul
@@ -0,0 +1,7 @@
+{
+    if 32 let x := 3
+}
+// ====
+// dialect: yul
+// ----
+// ParserError 2314: (12-15): Expected '{' but got reserved keyword 'let'
diff --git a/test/libyul/yulSyntaxTests/if_statement_invalid_4.yul b/test/libyul/yulSyntaxTests/if_statement_invalid_4.yul
new file mode 100644
index 000000000..ed9deeda6
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/if_statement_invalid_4.yul
@@ -0,0 +1,5 @@
+{
+    if calldatasize {}
+}
+// ----
+// ParserError 2314: (22-23): Expected '(' but got '{'
diff --git a/test/libyul/yulSyntaxTests/if_statement_scope_1.yul b/test/libyul/yulSyntaxTests/if_statement_scope_1.yul
new file mode 100644
index 000000000..3b49e4703
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/if_statement_scope_1.yul
@@ -0,0 +1,6 @@
+{
+	let x := 2
+	if 42 { x := 3 }
+}
+// ====
+// dialect: evm
diff --git a/test/libyul/yulSyntaxTests/if_statement_scope_2.yul b/test/libyul/yulSyntaxTests/if_statement_scope_2.yul
new file mode 100644
index 000000000..e86578812
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/if_statement_scope_2.yul
@@ -0,0 +1,8 @@
+{
+	if 32 { let x := 3 }
+	x := 2
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 4634: (25-26): Variable not found or variable not lvalue.
diff --git a/test/libyul/yulSyntaxTests/instructions_too_few_args_1.yul b/test/libyul/yulSyntaxTests/instructions_too_few_args_1.yul
new file mode 100644
index 000000000..e2b077423
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/instructions_too_few_args_1.yul
@@ -0,0 +1,5 @@
+{
+	pop(mul())
+}
+// ----
+// TypeError 7000: (7-10): Function expects 2 arguments but got 0.
diff --git a/test/libyul/yulSyntaxTests/instructions_too_few_args_2.yul b/test/libyul/yulSyntaxTests/instructions_too_few_args_2.yul
new file mode 100644
index 000000000..a43a19959
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/instructions_too_few_args_2.yul
@@ -0,0 +1,5 @@
+{
+	pop(mul(1))
+}
+// ----
+// TypeError 7000: (7-10): Function expects 2 arguments but got 1.
diff --git a/test/libyul/yulSyntaxTests/instructions_too_many_args.yul b/test/libyul/yulSyntaxTests/instructions_too_many_args.yul
new file mode 100644
index 000000000..eafa3d902
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/instructions_too_many_args.yul
@@ -0,0 +1,5 @@
+{
+	pop(mul(1, 2, 3))
+}
+// ----
+// TypeError 7000: (7-10): Function expects 2 arguments but got 3.
diff --git a/test/libyul/yulSyntaxTests/invalid_tuple_assignment.yul b/test/libyul/yulSyntaxTests/invalid_tuple_assignment.yul
new file mode 100644
index 000000000..94805f0fd
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/invalid_tuple_assignment.yul
@@ -0,0 +1,5 @@
+{
+	let x, y := 1
+}
+// ----
+// DeclarationError 3812: (3-16): Variable count mismatch: 2 variables and 1 values.
diff --git a/test/libyul/yulSyntaxTests/keywords.yul b/test/libyul/yulSyntaxTests/keywords.yul
new file mode 100644
index 000000000..00aec0c56
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/keywords.yul
@@ -0,0 +1,4 @@
+{
+	return (byte(1, 2), 2)
+	pop(address()) // this is valid (but unreachable) code
+}
diff --git a/test/libyul/yulSyntaxTests/name_clash_function_var_subscope.yul b/test/libyul/yulSyntaxTests/name_clash_function_var_subscope.yul
new file mode 100644
index 000000000..f35913215
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/name_clash_function_var_subscope.yul
@@ -0,0 +1,7 @@
+{
+	function g() {
+		let g := 0
+	}
+}
+// ----
+// DeclarationError 1395: (20-30): Variable name g already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/name_clash_function_var_subscope_reverse.yul b/test/libyul/yulSyntaxTests/name_clash_function_var_subscope_reverse.yul
new file mode 100644
index 000000000..548c72d31
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/name_clash_function_var_subscope_reverse.yul
@@ -0,0 +1,6 @@
+{
+	{ let g := 0 }
+	function g() {}
+}
+// ----
+// DeclarationError 1395: (5-15): Variable name g already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/name_clash_sub_scope.yul b/test/libyul/yulSyntaxTests/name_clash_sub_scope.yul
new file mode 100644
index 000000000..f671d0348
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/name_clash_sub_scope.yul
@@ -0,0 +1,7 @@
+{
+	function g() {
+		function g() {}
+	}
+}
+// ----
+// DeclarationError 6052: (20-35): Function name g already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/name_clash_sub_scope_reverse.yul b/test/libyul/yulSyntaxTests/name_clash_sub_scope_reverse.yul
new file mode 100644
index 000000000..3fd2015a4
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/name_clash_sub_scope_reverse.yul
@@ -0,0 +1,8 @@
+{
+	{
+		function g() {}
+	}
+	function g() {}
+}
+// ----
+// DeclarationError 6052: (7-22): Function name g already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/name_clashes.yul b/test/libyul/yulSyntaxTests/name_clashes.yul
new file mode 100644
index 000000000..19c5c9549
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/name_clashes.yul
@@ -0,0 +1,6 @@
+{
+    let g := 2
+    function g() { }
+}
+// ----
+// DeclarationError 1395: (6-16): Variable name g already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/number_literals_1.yul b/test/libyul/yulSyntaxTests/number_literals_1.yul
new file mode 100644
index 000000000..edfcc41b4
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/number_literals_1.yul
@@ -0,0 +1,3 @@
+{
+	let x := 1
+}
diff --git a/test/libyul/yulSyntaxTests/number_literals_2.yul b/test/libyul/yulSyntaxTests/number_literals_2.yul
new file mode 100644
index 000000000..7b054f0d3
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/number_literals_2.yul
@@ -0,0 +1,5 @@
+{
+	let x := .1
+}
+// ----
+// ParserError 4828: (12-14): Invalid number literal.
diff --git a/test/libyul/yulSyntaxTests/number_literals_3.yul b/test/libyul/yulSyntaxTests/number_literals_3.yul
new file mode 100644
index 000000000..acdffda51
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/number_literals_3.yul
@@ -0,0 +1,5 @@
+{
+	let x := 1e5
+}
+// ----
+// ParserError 4828: (12-15): Invalid number literal.
diff --git a/test/libyul/yulSyntaxTests/number_literals_4.yul b/test/libyul/yulSyntaxTests/number_literals_4.yul
new file mode 100644
index 000000000..58b25bf57
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/number_literals_4.yul
@@ -0,0 +1,5 @@
+{
+	let x := 67.235
+}
+// ----
+// ParserError 4828: (12-18): Invalid number literal.
diff --git a/test/libyul/yulSyntaxTests/number_literals_5.yul b/test/libyul/yulSyntaxTests/number_literals_5.yul
new file mode 100644
index 000000000..5fd87743d
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/number_literals_5.yul
@@ -0,0 +1,5 @@
+{
+	let x := 0x1ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
+}
+// ----
+// TypeError 6708: (12-79): Number literal too large (> 256 bits)
diff --git a/test/libyul/yulSyntaxTests/opcode_for_function_args_1.yul b/test/libyul/yulSyntaxTests/opcode_for_function_args_1.yul
new file mode 100644
index 000000000..00c357bb4
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/opcode_for_function_args_1.yul
@@ -0,0 +1,5 @@
+{
+	function f(gas) {}
+}
+// ----
+// ParserError 5568: (14-17): Cannot use builtin function name "gas" as identifier name.
diff --git a/test/libyul/yulSyntaxTests/opcode_for_function_args_2.yul b/test/libyul/yulSyntaxTests/opcode_for_function_args_2.yul
new file mode 100644
index 000000000..989cfce9e
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/opcode_for_function_args_2.yul
@@ -0,0 +1,5 @@
+{
+	function f() -> gas {}
+}
+// ----
+// ParserError 5568: (19-22): Cannot use builtin function name "gas" as identifier name.
diff --git a/test/libyul/yulSyntaxTests/opcode_for_functions.yul b/test/libyul/yulSyntaxTests/opcode_for_functions.yul
new file mode 100644
index 000000000..0efc7cbcc
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/opcode_for_functions.yul
@@ -0,0 +1,5 @@
+{
+	function gas() {}
+}
+// ----
+// ParserError 5568: (12-15): Cannot use builtin function name "gas" as identifier name.
diff --git a/test/libyul/yulSyntaxTests/selfdestruct.yul b/test/libyul/yulSyntaxTests/selfdestruct.yul
new file mode 100644
index 000000000..deb6d1dae
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/selfdestruct.yul
@@ -0,0 +1,3 @@
+{
+	selfdestruct(0x02)
+}
diff --git a/test/libyul/yulSyntaxTests/simple_instructions.yul b/test/libyul/yulSyntaxTests/simple_instructions.yul
new file mode 100644
index 000000000..d3f9f023b
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/simple_instructions.yul
@@ -0,0 +1,3 @@
+{
+	let y := mul(0x10, mul(0x20, mload(0x40)))
+}
diff --git a/test/libyul/yulSyntaxTests/smoke_test.yul b/test/libyul/yulSyntaxTests/smoke_test.yul
new file mode 100644
index 000000000..f87fddff5
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/smoke_test.yul
@@ -0,0 +1 @@
+{ { } }
diff --git a/test/libyul/yulSyntaxTests/surplus_input.yul b/test/libyul/yulSyntaxTests/surplus_input.yul
new file mode 100644
index 000000000..3db8feec9
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/surplus_input.yul
@@ -0,0 +1,4 @@
+{}
+{}
+// ----
+// ParserError 2314: (3-4): Expected end of source but got '{'
diff --git a/test/libyul/yulSyntaxTests/switch_default_before_case.yul b/test/libyul/yulSyntaxTests/switch_default_before_case.yul
new file mode 100644
index 000000000..14434b7ac
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_default_before_case.yul
@@ -0,0 +1,7 @@
+{
+    switch 42
+    default {}
+    case 1 {}
+}
+// ----
+// ParserError 4904: (35-39): Case not allowed after default case.
diff --git a/test/libyul/yulSyntaxTests/switch_duplicate_default.yul b/test/libyul/yulSyntaxTests/switch_duplicate_default.yul
new file mode 100644
index 000000000..4b73953fe
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_duplicate_default.yul
@@ -0,0 +1,7 @@
+{
+    switch 42
+    default {}
+    default {}
+}
+// ----
+// ParserError 6931: (35-42): Only one default case allowed.
diff --git a/test/libyul/yulSyntaxTests/switch_invalid_body.yul b/test/libyul/yulSyntaxTests/switch_invalid_body.yul
new file mode 100644
index 000000000..b6c4816fb
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_invalid_body.yul
@@ -0,0 +1,8 @@
+{
+    switch 42
+    case 1 mul
+    case 2 {}
+    default {}
+}
+// ----
+// ParserError 2314: (27-30): Expected '{' but got identifier
diff --git a/test/libyul/yulSyntaxTests/switch_invalid_case.yul b/test/libyul/yulSyntaxTests/switch_invalid_case.yul
new file mode 100644
index 000000000..0aa52d371
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_invalid_case.yul
@@ -0,0 +1,8 @@
+{
+    switch 42
+    case mul(1, 2) {}
+    case 2 {}
+    default {}
+}
+// ----
+// ParserError 4805: (28-29): Literal expected.
diff --git a/test/libyul/yulSyntaxTests/switch_invalid_expr_1.yul b/test/libyul/yulSyntaxTests/switch_invalid_expr_1.yul
new file mode 100644
index 000000000..6609a9ef3
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_invalid_expr_1.yul
@@ -0,0 +1,7 @@
+{
+    switch {}
+    case 1 {}
+    default {}
+}
+// ----
+// ParserError 1856: (13-14): Literal or identifier expected.
diff --git a/test/libyul/yulSyntaxTests/switch_invalid_expr_2.yul b/test/libyul/yulSyntaxTests/switch_invalid_expr_2.yul
new file mode 100644
index 000000000..842fa02f3
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_invalid_expr_2.yul
@@ -0,0 +1,7 @@
+{
+    switch mload
+    case 1 {}
+    default {}
+}
+// ----
+// ParserError 2314: (23-27): Expected '(' but got reserved keyword 'case'
diff --git a/test/libyul/yulSyntaxTests/switch_invalid_expr_3.yul b/test/libyul/yulSyntaxTests/switch_invalid_expr_3.yul
new file mode 100644
index 000000000..6ab68d7ea
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_invalid_expr_3.yul
@@ -0,0 +1,9 @@
+{
+	switch mstore(1, 1)
+	case 1 {}
+	default {}
+}
+// ====
+// dialect: evm
+// ----
+// TypeError 3950: (10-22): Expected expression to evaluate to one value, but got 0 values instead.
diff --git a/test/libyul/yulSyntaxTests/switch_statement_1.yul b/test/libyul/yulSyntaxTests/switch_statement_1.yul
new file mode 100644
index 000000000..13115a922
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_statement_1.yul
@@ -0,0 +1,3 @@
+{ switch 42 default {} }
+// ----
+// Warning 9592: (2-22): "switch" statement with only a default case.
diff --git a/test/libyul/yulSyntaxTests/switch_statement_2.yul b/test/libyul/yulSyntaxTests/switch_statement_2.yul
new file mode 100644
index 000000000..f58eb3a7a
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_statement_2.yul
@@ -0,0 +1,8 @@
+{
+    { switch 42 case 1 {} }
+    { switch 42 case 1 {} case 2 {} }
+    { switch 42 case 1 {} default {} }
+    { switch 42 case 1 {} case 2 {} default {} }
+    { switch mul(1, 2) case 1 {} case 2 {} default {} }
+    { function f() -> x {} switch f() case 1 {} case 2 {} default {} }
+}
diff --git a/test/libyul/yulSyntaxTests/switch_statement_duplicate_case.yul b/test/libyul/yulSyntaxTests/switch_statement_duplicate_case.yul
new file mode 100644
index 000000000..5c9bbe045
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_statement_duplicate_case.yul
@@ -0,0 +1,10 @@
+{
+	switch 42
+	case 1 {}
+	case 1 {}
+	default {}
+}
+// ====
+// dialect: evm
+// ----
+// DeclarationError 6792: (25-34): Duplicate case defined.
diff --git a/test/libyul/yulSyntaxTests/switch_statement_no_access.yul b/test/libyul/yulSyntaxTests/switch_statement_no_access.yul
new file mode 100644
index 000000000..4f40f2640
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/switch_statement_no_access.yul
@@ -0,0 +1,5 @@
+{
+    switch 42
+}
+// ----
+// ParserError 2418: (16-17): Switch statement without any cases.
diff --git a/test/libyul/yulSyntaxTests/vardecl.yul b/test/libyul/yulSyntaxTests/vardecl.yul
new file mode 100644
index 000000000..64fd69d6f
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/vardecl.yul
@@ -0,0 +1,5 @@
+{
+    let x := 7
+}
+// ====
+// dialect: yul
diff --git a/test/libyul/yulSyntaxTests/vardecl_bool.yul b/test/libyul/yulSyntaxTests/vardecl_bool.yul
new file mode 100644
index 000000000..93ec762b0
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/vardecl_bool.yul
@@ -0,0 +1,6 @@
+{
+    let x := true
+    let y := false
+}
+// ====
+// dialect: evm
diff --git a/test/libyul/yulSyntaxTests/vardecl_complex.yul b/test/libyul/yulSyntaxTests/vardecl_complex.yul
new file mode 100644
index 000000000..117e1d997
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/vardecl_complex.yul
@@ -0,0 +1,4 @@
+{
+    let y := 2
+    let x := add(add(7, mul(6, y)), mul(7, 8))
+}
diff --git a/test/libyul/yulSyntaxTests/vardecl_empty.yul b/test/libyul/yulSyntaxTests/vardecl_empty.yul
new file mode 100644
index 000000000..dc536c67a
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/vardecl_empty.yul
@@ -0,0 +1,3 @@
+{
+	let x
+}
diff --git a/test/libyul/yulSyntaxTests/vardecl_multi.yul b/test/libyul/yulSyntaxTests/vardecl_multi.yul
new file mode 100644
index 000000000..abf04b746
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/vardecl_multi.yul
@@ -0,0 +1,4 @@
+{
+    function f() -> x, y {}
+    let x, y := f()
+}
diff --git a/test/libyul/yulSyntaxTests/vardecl_multi_conflict.yul b/test/libyul/yulSyntaxTests/vardecl_multi_conflict.yul
new file mode 100644
index 000000000..c40c79740
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/vardecl_multi_conflict.yul
@@ -0,0 +1,6 @@
+{
+	function f() -> x, y {}
+	let x, x := f()
+}
+// ----
+// DeclarationError 1395: (28-43): Variable name x already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/vardecl_name_clashes.yul b/test/libyul/yulSyntaxTests/vardecl_name_clashes.yul
new file mode 100644
index 000000000..2906078cf
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/vardecl_name_clashes.yul
@@ -0,0 +1,6 @@
+{
+	let x := 1
+	let x := 2
+}
+// ----
+// DeclarationError 1395: (15-25): Variable name x already taken in this scope.
diff --git a/test/libyul/yulSyntaxTests/variable_access_cross_funcs.yul b/test/libyul/yulSyntaxTests/variable_access_cross_funcs.yul
new file mode 100644
index 000000000..7ddbacb8d
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/variable_access_cross_funcs.yul
@@ -0,0 +1,8 @@
+{
+	let x := 2
+	function g() {
+		pop(x)
+	}
+}
+// ----
+// DeclarationError 8198: (36-37): Identifier not found.
diff --git a/test/libyul/yulSyntaxTests/variable_use_before_decl_1.yul b/test/libyul/yulSyntaxTests/variable_use_before_decl_1.yul
new file mode 100644
index 000000000..76bcd1d0d
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/variable_use_before_decl_1.yul
@@ -0,0 +1,6 @@
+{
+	x := 2
+	let x := 3
+}
+// ----
+// DeclarationError 1133: (3-4): Variable x used before it was declared.
diff --git a/test/libyul/yulSyntaxTests/variable_use_before_decl_2.yul b/test/libyul/yulSyntaxTests/variable_use_before_decl_2.yul
new file mode 100644
index 000000000..c6612fd8c
--- /dev/null
+++ b/test/libyul/yulSyntaxTests/variable_use_before_decl_2.yul
@@ -0,0 +1,6 @@
+{
+	let x := mul(2, x)
+}
+
+// ----
+// DeclarationError 4990: (19-20): Variable x used before it was declared.