parser: disallow statements after a return, branch check $if, $else, switch, and loops correctly

vlib/builtin/array.v

@@ -77,7 +77,6 @@ pub fn (a mut array) sort_with_compare(compare voidptr) {
 pub fn (a mut array) insert(i int, val voidptr) {
 	if i >= a.len {
 		panic('array.insert: index larger than length')
-		return
 	}
 	a._push(val)
 	size := a.element_size

vlib/builtin/builtin.v

@@ -18,7 +18,9 @@ fn on_panic(f fn (int) int) {
 }
 
 pub fn print_backtrace() {
-	return
+	if true {
+		return // TODO
+	}
 	$if mac {
 		buffer := [100]voidptr
 		nr_ptrs := C.backtrace(buffer, 100)

vlib/builtin/map.v

@@ -94,8 +94,7 @@ fn (n & Node) find(key string, out voidptr, element_size int) bool{
 		}  else { 
 			return n.right.find(key, out, element_size) 
 		} 
-	} 
-	return false 
+	}
 } 
 
 // same as `find`, but doesn't return a value. Used by `exists` 
@@ -116,8 +115,7 @@ fn (n & Node) find2(key string, element_size int) bool{
 		}  else { 
 			return n.right.find2(key, element_size) 
 		} 
-	} 
-	return false 
+	}
 } 
 
 fn (m mut map) _set(key string, val voidptr) {
@@ -215,7 +213,6 @@ pub fn (m mut map) delete(key string) {
 
 pub fn (m map) exists(key string) bool {
 	panic('map.exists(key) was removed from the language. Use `key in map` instead.') 
-	return false 
 }
 
 fn (m map) _exists(key string) bool {

vlib/builtin/string.v

@@ -40,7 +40,6 @@ pub fn tos(s byteptr, len int) string {
 pub fn tos_clone(s byteptr) string {
 	if isnil(s) {
 		panic('tos: nil string')
-		return string{}
 	}
 	len := strlen(s)
 	res := tos(s, len)
@@ -52,7 +51,6 @@ pub fn tos_clone(s byteptr) string {
 fn tos2(s byteptr) string {
 	if isnil(s) {
 		panic('tos2: nil string')
-		return string{}
 	}
 	len := C.strlen(s)
 	res := tos(s, len)
@@ -337,7 +335,6 @@ pub fn (s string) right(n int) string {
 pub fn (s string) substr(start, end int) string {
 	if start > end || start > s.len || end > s.len || start < 0 || end < 0 {
 		panic('substr($start, $end) out of bounds (len=$s.len)')
-		return ''
 	}
 	len := end - start
 

vlib/freetype/freetype.v

@@ -84,7 +84,8 @@ struct Cfg {
 fn ft_load_char(_face Face, code i64) Character {
 	// #FT_Face face = *(FT_Face*)(_face); FT_ULong code = *(FT_ULong*)(code);
 	# FT_Face face = *((FT_Face*)_face.cobj);
-	# if (FT_Load_Char(face, code, FT_LOAD_RENDER))
+	# int condition = FT_Load_Char(face, code, FT_LOAD_RENDER);
+	if (C.condition != 0)
 	{
 		println('freetype: Failed to load Glyph')
 		exit(1)
@@ -170,7 +171,8 @@ pub fn new_context(cfg gg.Cfg) *Context {
 	}
 	println('Trying to load font from $font_path')
 	# FT_Face face;
-	# if (FT_New_Face(ft, font_path.str, 0, &face))
+	# int condition = FT_New_Face(ft, font_path.str, 0, &face);
+	if (C.condition != 0)
 	// # if (FT_New_Face(ft, "/Library/Fonts/Courier New.ttf", 0, &face))
 	// # if (FT_New_Face(ft, "/System/Library/Fonts/Apple Color Emoji.ttc", 0, &face))
 	{

vlib/gg/gg.v

@@ -274,7 +274,7 @@ pub fn (ctx &GG) draw_rect2(x, y, w, h f32, c gx.Color) {
 fn todo_remove_me(cfg Cfg, scale int) { 
 	// Can only have text in ortho mode
 	if !cfg.use_ortho {
-		return &GG{} 
+		return
 	}
 	mut width := cfg.width * scale
 	mut height := cfg.height * scale

vlib/http/http.v

@@ -169,22 +169,18 @@ fn build_request_headers(user_agent, method, host_name, path string) string {
 
 pub fn unescape_url(s string) string {
 	panic('http.unescape_url() was replaced with urllib.query_unescape()') 
-	return '' 
 }
 
 pub fn escape_url(s string) string {
 	panic('http.escape_url() was replaced with urllib.query_escape()') 
-	return '' 
 }
 
 pub fn unescape(s string) string {
 	panic('http.unescape() was replaced with http.unescape_url()') 
-	return '' 
 }
 
 pub fn escape(s string) string {
 	panic('http.escape() was replaced with http.escape_url()') 
-	return '' 
 }
 
 type wsfn fn (s string, ptr voidptr)

vlib/json/json_test.v

@@ -9,7 +9,6 @@ fn test_parse_user() {
 	s := '{"age": 10, "nums": [1,2,3]}'
 	u := json.decode(User, s) or {
 		exit(1) 
-		return
 	}
 	assert u.age == 10
 	assert u.nums.len == 3

vlib/log/log.v

@@ -39,7 +39,6 @@ fn (l Log) log_file(s string, e string) {
     filename := l.output
     f := os.open_append(l.output) or {
         panic('error reading file $filename')
-        return
     }
     timestamp := time.now().format_ss()
     f.writeln('$timestamp [$e] $s')

vlib/math/fractions/fraction.v

@@ -19,7 +19,6 @@ pub fn fraction(n i64, d i64) Fraction{
 	} 
 	else {
 		panic('Denominator cannot be zero')
-		return Fraction{} // TODO remove return
 	}
 }
 

vlib/os/os.v

@@ -870,6 +870,7 @@ pub fn fork() int {
 		pid := C.fork()
 		return pid
 	}
+	panic('os.fork not supported in windows') // TODO
 }
 
 pub fn wait() int {
@@ -877,6 +878,7 @@ pub fn wait() int {
 		pid := C.wait(0)
 		return pid
 	}
+	panic('os.wait not supported in windows') // TODO
 }
 
 pub fn file_last_mod_unix(path string) int {

vlib/os/os_test.v

@@ -27,7 +27,6 @@ fn test_write_and_read_string_to_file() {
   
   read_hello := os.read_file(filename) or {
     panic('error reading file $filename')
-    return
   }
   assert hello == read_hello
 

vlib/os/os_win.v

@@ -40,6 +40,7 @@ pub fn get_module_filename(handle HANDLE) ?string {
             return error('Cannot get file name from handle.')
         }
     }
+    panic('this should be unreachable') // TODO remove unreachable after loop
 }
 
 // Ref - https://docs.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-formatmessagea#parameters

vlib/vweb/tmpl/tmpl.v

@@ -17,13 +17,11 @@ pub fn compile_template(path string) string {
 	//lines := os.read_lines(path)
 	mut html := os.read_file(path) or {
 		panic('html failed')
-		return ''
 	} 
 	mut	header := ''
 	if os.file_exists('header.html') { 
 		h := os.read_file('header.html') or {
 			panic('html failed')
-			return ''
 		} 
 		header = h.replace('\'', '"') 
 	} 

vlib/vweb/vweb.v

@@ -85,13 +85,12 @@ $html
 
 pub fn run<T>(port int) { 
 	println('Running vweb app on http://localhost:$port ...') 
-	l := net.listen(port) or { panic('failed to listen') return } 
+	l := net.listen(port) or { panic('failed to listen') } 
 	mut app := T{} 
 	app.init() 
 	for {
 		conn := l.accept() or {
 			panic('accept() failed') 
-			return 
 		} 
 		// TODO move this to handle_conn<T>(conn, app)
 		s := conn.read_line()