parser/checker: `if select { ... } {` (#6434)

doc/docs.md

@@ -1891,6 +1891,8 @@ if select {
     ch <- a {
         ...
     }
+} {
+    // channel was open
 } else {
     // channel is closed
 }

vlib/sync/channel_select_3_test.v

@@ -91,7 +91,8 @@ fn test_select_blocks() {
 	ch1.close()
 	ch2.close()
 	mut h := 7
-	u := select {
+	mut is_open := true
+	if select {
 		b := <- ch2 {
 			h = 0
 		}
@@ -101,11 +102,15 @@ fn test_select_blocks() {
 		else {
 			h = 2
 		}
+	} {
+		panic('channel is still open')
+	} else {
+		is_open = false
 	}
 	// no branch should have run
 	assert h == 7
 	// since all channels are closed `select` should return `false`
-	assert u == false
+	assert is_open == false
 }
 
 			

vlib/v/checker/checker.v

@@ -3220,6 +3220,7 @@ pub fn (mut c Checker) if_expr(mut node ast.IfExpr) table.Type {
 				should_skip = c.comp_if_branch(branch.cond, branch.pos)
 			} else {
 				// check condition type is boolean
+				c.expected_type = table.bool_type
 				cond_typ := c.expr(branch.cond)
 				if cond_typ.idx() !in [table.bool_type_idx, table.void_type_idx] && !c.pref.translated {
 					// void types are skipped, because they mean the var was initialized incorrectly

vlib/v/parser/parser.v

@@ -1076,7 +1076,8 @@ pub fn (mut p Parser) name_expr() ast.Expr {
 	} else if (p.peek_tok.kind == .lcbr ||
 		(p.peek_tok.kind == .lt && lit0_is_capital)) &&
 		(!p.inside_match || (p.inside_select && prev_tok_kind == .arrow && lit0_is_capital)) && !p.inside_match_case &&
-		!p.inside_if && !p.inside_for { // && (p.tok.lit[0].is_capital() || p.builtin_mod) {
+		(!p.inside_if || p.inside_select) &&
+		(!p.inside_for || p.inside_select) { // && (p.tok.lit[0].is_capital() || p.builtin_mod) {
 		return p.struct_init(false) // short_syntax: false
 	} else if p.peek_tok.kind == .dot && (lit0_is_capital && !known_var && language == .v) {
 		// `Color.green`