match: implement exhaustive match for bool values (#7761)

vlib/v/checker/checker.v

@@ -3673,11 +3673,10 @@ pub fn (mut c Checker) match_expr(mut node ast.MatchExpr) table.Type {
 	return ret_type
 }
 
-fn (mut c Checker) match_exprs(mut node ast.MatchExpr, type_sym table.TypeSymbol) {
+fn (mut c Checker) match_exprs(mut node ast.MatchExpr, cond_type_sym table.TypeSymbol) {
 	// branch_exprs is a histogram of how many times
 	// an expr was used in the match
 	mut branch_exprs := map[string]int{}
-	cond_type_sym := c.table.get_type_symbol(node.cond_type)
 	for branch_i, _ in node.branches {
 		mut branch := node.branches[branch_i]
 		mut expr_types := []ast.Type{}
@@ -3860,27 +3859,37 @@ fn (mut c Checker) match_exprs(mut node ast.MatchExpr, type_sym table.TypeSymbol
 	// by listing all variants or values
 	mut is_exhaustive := true
 	mut unhandled := []string{}
-	match mut type_sym.info {
-		table.SumType {
-			for v in type_sym.info.variants {
-				v_str := c.table.type_to_str(v)
-				if v_str !in branch_exprs {
-					is_exhaustive = false
-					unhandled << '`$v_str`'
-				}
+	if node.cond_type == table.bool_type {
+		variants := ['true', 'false']
+		for v in variants {
+			if v !in branch_exprs {
+				is_exhaustive = false
+				unhandled << '`$v`'
 			}
 		}
-		//
-		table.Enum {
-			for v in type_sym.info.vals {
-				if v !in branch_exprs {
-					is_exhaustive = false
-					unhandled << '`.$v`'
+	} else {
+		match mut cond_type_sym.info {
+			table.SumType {
+				for v in cond_type_sym.info.variants {
+					v_str := c.table.type_to_str(v)
+					if v_str !in branch_exprs {
+						is_exhaustive = false
+						unhandled << '`$v_str`'
+					}
 				}
 			}
-		}
-		else {
-			is_exhaustive = false
+			//
+			table.Enum {
+				for v in cond_type_sym.info.vals {
+					if v !in branch_exprs {
+						is_exhaustive = false
+						unhandled << '`.$v`'
+					}
+				}
+			}
+			else {
+				is_exhaustive = false
+			}
 		}
 	}
 	mut else_branch := node.branches[node.branches.len - 1]

vlib/v/tests/complex_assign_test.v

@@ -21,7 +21,6 @@ fn test_assign_multi_expr_func() {
 	g, h := match true {
 		true { multireturner(0, 'good') }
 		false { multireturner(100, 'bad') }
-		else { multireturner(200, 'bad') }
 	}
 	assert g == 1
 	assert h == 'good'
@@ -36,7 +35,6 @@ fn test_assign_multi_expr() {
 	a,b,c := match false {
 		true { 1,2,3 }
 		false { 4,5,6 }
-		else { 7,8,9 }
 	}
 	assert a == 4
 	assert b == 5