parser, checker: fix static method naming and generic call (#18694)

vlib/v/ast/str.v

@@ -6,6 +6,24 @@ module ast
 import v.util
 import strings
 
+// get_name returns the real name for the function declaration
+pub fn (f &FnDecl) get_name() string {
+	if f.is_static_type_method {
+		return f.name.all_after_last('__static__')
+	} else {
+		return f.name
+	}
+}
+
+// get_name returns the real name for the function calling
+pub fn (f &CallExpr) get_name() string {
+	if f.name != '' && f.name.all_after_last('.')[0].is_capital() && f.name.contains('__static__') {
+		return f.name.replace('__static__', '.')
+	} else {
+		return f.name
+	}
+}
+
 pub fn (node &FnDecl) modname() string {
 	if node.mod != '' {
 		return node.mod
@@ -373,18 +391,18 @@ pub fn (x Expr) str() string {
 				return '${x.left.str()}.${x.name}(${sargs})${propagate_suffix}'
 			}
 			if x.name.starts_with('${x.mod}.') {
-				return util.strip_main_name('${x.name}(${sargs})${propagate_suffix}')
+				return util.strip_main_name('${x.get_name()}(${sargs})${propagate_suffix}')
 			}
 			if x.mod == '' && x.name == '' {
 				return x.left.str() + '(${sargs})${propagate_suffix}'
 			}
 			if x.name.contains('.') {
-				return '${x.name}(${sargs})${propagate_suffix}'
+				return '${x.get_name()}(${sargs})${propagate_suffix}'
 			}
 			if x.name.contains('__static__') {
-				return '${x.mod}.${x.name}(${sargs})${propagate_suffix}'
+				return '${x.mod}.${x.get_name()}(${sargs})${propagate_suffix}'
 			}
-			return '${x.mod}.${x.name}(${sargs})${propagate_suffix}'
+			return '${x.mod}.${x.get_name()}(${sargs})${propagate_suffix}'
 		}
 		CharLiteral {
 			return '`${x.val}`'

vlib/v/checker/assign.v

@@ -87,14 +87,14 @@ fn (mut c Checker) assign_stmt(mut node ast.AssignStmt) {
 				// If it's a void type, it's an unknown variable, already had an error earlier.
 				return
 			}
-			c.error('assignment mismatch: ${node.left.len} variable(s) but `${right_first.name}()` returns ${right_len} value(s)',
+			c.error('assignment mismatch: ${node.left.len} variable(s) but `${right_first.get_name()}()` returns ${right_len} value(s)',
 				node.pos)
 		} else if right_first is ast.ParExpr {
 			mut right_next := right_first
 			for {
 				if mut right_next.expr is ast.CallExpr {
 					if right_next.expr.return_type == ast.void_type {
-						c.error('assignment mismatch: expected ${node.left.len} value(s) but `${right_next.expr.name}()` returns ${right_len} value(s)',
+						c.error('assignment mismatch: expected ${node.left.len} value(s) but `${right_next.expr.get_name()}()` returns ${right_len} value(s)',
 							node.pos)
 					}
 					break

vlib/v/checker/fn.v

@@ -87,7 +87,7 @@ fn (mut c Checker) fn_decl(mut node ast.FnDecl) {
 		}
 	}
 	if node.language == .v && !c.is_builtin_mod && !node.is_anon {
-		c.check_valid_snake_case(node.name, 'function name', node.pos)
+		c.check_valid_snake_case(node.get_name(), 'function name', node.pos)
 		if !node.is_method && node.mod == 'main' && node.short_name in c.table.builtin_pub_fns {
 			c.error('cannot redefine builtin public function `${node.short_name}`', node.pos)
 		}
@@ -944,7 +944,7 @@ fn (mut c Checker) fn_call(mut node ast.CallExpr, mut continue_check &bool) ast.
 				return ast.void_type
 			}
 		}
-		c.error('unknown function: ${fn_name}', node.pos)
+		c.error('unknown function: ${node.get_name()}', node.pos)
 		return ast.void_type
 	}
 	node.is_file_translated = func.is_file_translated

vlib/v/checker/tests/func_with_static_keyword_err.out

@@ -0,0 +1,12 @@
+vlib/v/checker/tests/func_with_static_keyword_err.vv:6:2: warning: unused variable: `a`
+    4 | 
+    5 | fn main() {
+    6 |     a := a__static__b()
+      |     ^
+    7 | }
+vlib/v/checker/tests/func_with_static_keyword_err.vv:6:4: error: assignment mismatch: 1 variable(s) but `a__static__b()` returns 2 value(s)
+    4 | 
+    5 | fn main() {
+    6 |     a := a__static__b()
+      |       ~~
+    7 | }

vlib/v/checker/tests/func_with_static_keyword_err.vv

@@ -0,0 +1,7 @@
+fn a__static__b() (int,int) {
+	return 1,2
+}
+
+fn main() {
+	a := a__static__b()
+}

vlib/v/checker/tests/static_method_multi_return_err.out

@@ -0,0 +1,7 @@
+vlib/v/checker/tests/static_method_multi_return_err.vv:10:6: error: assignment mismatch: 1 variable(s) but `SomeStruct.static_method()` returns 2 value(s)
+    8 | 
+    9 | fn main() {
+   10 |     val := SomeStruct.static_method()
+      |         ~~
+   11 |     println(val)
+   12 | }

vlib/v/checker/tests/static_method_multi_return_err.vv

@@ -0,0 +1,12 @@
+struct SomeStruct {
+	name string
+}
+
+fn SomeStruct.static_method() (string, int) {
+	return 'hello', 100
+}
+
+fn main() {
+	val := SomeStruct.static_method()
+	println(val)
+}

vlib/v/checker/tests/static_method_not_found_err.out

@@ -0,0 +1,13 @@
+vlib/v/checker/tests/static_method_not_found_err.vv:10:9: error: unknown function: TestStruct.static_method
+    8 | 
+    9 | fn main() {
+   10 |     val := TestStruct.static_method()
+      |            ~~~~~~~~~~~~~~~~~~~~~~~~~~
+   11 |     println(val)
+   12 | }
+vlib/v/checker/tests/static_method_not_found_err.vv:11:2: error: `println` can not print void expressions
+    9 | fn main() {
+   10 |     val := TestStruct.static_method()
+   11 |     println(val)
+      |     ~~~~~~~~~~~~
+   12 | }

vlib/v/checker/tests/static_method_not_found_err.vv

@@ -0,0 +1,12 @@
+struct TestStruct {
+	name string
+}
+
+fn (f TestStruct) static_method() string {
+	return 'hello'
+}
+
+fn main() {
+	val := TestStruct.static_method()
+	println(val)
+}

vlib/v/parser/fn.v

@@ -14,7 +14,7 @@ fn (mut p Parser) call_expr(language ast.Language, mod string) ast.CallExpr {
 	mut is_static_type_method := language == .v && name[0].is_capital() && p.tok.kind == .dot
 	if is_static_type_method {
 		p.check(.dot)
-		name = name.to_lower() + '__static__' + p.check_name()
+		name = name + '__static__' + p.check_name()
 	}
 	mut fn_name := if language == .c {
 		'C.${name}'
@@ -294,6 +294,7 @@ fn (mut p Parser) fn_decl() ast.FnDecl {
 	mut type_sym := p.table.sym(rec.typ)
 	name_pos := p.tok.pos()
 	if p.tok.kind == .name {
+		mut check_name := ''
 		// TODO high order fn
 		is_static_type_method = p.tok.lit.len > 0 && p.tok.lit[0].is_capital()
 			&& p.peek_tok.kind == .dot && language == .v // `fn Foo.bar() {}`
@@ -301,12 +302,14 @@ fn (mut p Parser) fn_decl() ast.FnDecl {
 			type_name := p.tok.lit // "Foo"
 			rec.typ = p.parse_type()
 			p.check(.dot)
-			name = type_name.to_lower() + '__static__' + p.check_name() // "foo__bar"
+			check_name = p.check_name()
+			name = type_name + '__static__' + check_name // "foo__bar"
 		} else {
-			name = if language == .js { p.check_js_name() } else { p.check_name() }
+			check_name = if language == .js { p.check_js_name() } else { p.check_name() }
+			name = check_name
 		}
-		if language == .v && !p.pref.translated && !p.is_translated && util.contains_capital(name)
-			&& !p.builtin_mod {
+		if language == .v && !p.pref.translated && !p.is_translated
+			&& util.contains_capital(check_name) && !p.builtin_mod {
 			p.error_with_pos('function names cannot contain uppercase letters, use snake_case instead',
 				name_pos)
 			return ast.FnDecl{

vlib/v/parser/parser.v

@@ -2630,11 +2630,12 @@ fn (mut p Parser) name_expr() ast.Expr {
 		// type cast. TODO: finish
 		// if name in ast.builtin_type_names_to_idx {
 		// handle the easy cases first, then check for an already known V typename, not shadowed by a local variable
-		if is_mod_cast || is_c_pointer_cast || is_c_type_cast || is_js_cast
-			|| is_generic_cast || (language == .v && name.len > 0 && (name[0].is_capital()
+		if (is_option || p.peek_tok.kind in [.lsbr, .lt, .lpar]) && (is_mod_cast
+			|| is_c_pointer_cast || is_c_type_cast || is_js_cast || is_generic_cast
+			|| (language == .v && name.len > 0 && (name[0].is_capital()
 			|| (!known_var && (name in p.table.type_idxs
 			|| name_w_mod in p.table.type_idxs))
-			|| name.all_after_last('.')[0].is_capital())) {
+			|| name.all_after_last('.')[0].is_capital()))) {
 			// MainLetter(x) is *always* a cast, as long as it is not `C.`
 			// TODO handle C.stat()
 			start_pos := p.tok.pos()
@@ -2673,7 +2674,6 @@ fn (mut p Parser) name_expr() ast.Expr {
 			p.expr_mod = ''
 			return node
 		} else {
-			// fn call
 			// fn_call
 			if is_option {
 				p.unexpected_with_pos(p.prev_tok.pos(),

vlib/v/parser/tests/method_call_receiver_err.out

@@ -12,7 +12,7 @@ vlib/v/parser/tests/method_call_receiver_err.vv:8:7: warning: unused variable: `
       |          ~~~~~~
     9 |         println(S1.method_hello('yo'))
    10 |     }
-vlib/v/parser/tests/method_call_receiver_err.vv:9:11: error: unknown function: s1__static__method_hello
+vlib/v/parser/tests/method_call_receiver_err.vv:9:11: error: unknown function: S1.method_hello
     7 | 
     8 |     $for method in S1.methods {
     9 |         println(S1.method_hello('yo'))

vlib/v/tests/generic_static_method_test.v

@@ -0,0 +1,12 @@
+struct SomeStruct {
+	name string
+}
+
+fn SomeStruct.static_method[T]() string {
+	return 'hello'
+}
+
+fn test_main() {
+	val := SomeStruct.static_method[string]()
+	assert val == 'hello'
+}