parser: force `...` rather than `..` in matches for inclusive ranges (#5852)

vlib/v/checker/checker.v

@@ -2616,7 +2616,7 @@ fn (mut c Checker) match_exprs(mut node ast.MatchExpr, type_sym table.TypeSymbol
 					typ := c.table.type_to_str(c.expr(expr.low))
 					c.error('cannot use type `$typ` in match range', branch.pos)
 				}
-				for i in low .. high {
+				for i in low..high + 1 {
 					key = i.str()
 					val := if key in branch_exprs { branch_exprs[key] } else { 0 }
 					if val == 1 {

vlib/v/checker/tests/match_duplicate_branch.out

@@ -35,7 +35,7 @@ vlib/v/checker/tests/match_duplicate_branch.v:43:3: error: match case `2` is han
    45 |     }
 vlib/v/checker/tests/match_duplicate_branch.v:51:3: error: match case `3` is handled more than once
    49 |     match i {
-   50 |         1..5 { println('1 to 4') }
+   50 |         1...5 { println('1 to 5') }
    51 |         3 { println('3') }
       |         ~~~
    52 |         else { println('else') }

vlib/v/checker/tests/match_duplicate_branch.vv

@@ -47,7 +47,7 @@ fn test_int(i int) {
 
 fn test_range(i int) {
 	match i {
-		1..5 { println('1 to 4') }
+		1...5 { println('1 to 5') }
 		3 { println('3') }
 		else { println('else') }
 	}

vlib/v/gen/cgen.v

@@ -2242,7 +2242,7 @@ fn (mut g Gen) match_expr(node ast.MatchExpr) {
 					g.expr(expr.low)
 					g.write(' && ')
 					g.expr(node.cond)
-					g.write(' < ')
+					g.write(' <= ')
 					g.expr(expr.high)
 					g.write(')')
 				} else {

vlib/v/parser/if.v

@@ -188,6 +188,8 @@ fn (mut p Parser) match_expr() ast.MatchExpr {
 				expr := p.expr(0)
 				p.inside_match_case = false
 				if p.tok.kind == .dotdot {
+					p.error_with_pos('match only supports inclusive (`...`) ranges, not exclusive (`..`)', p.tok.position())
+				} else if p.tok.kind == .ellipsis {
 					p.next()
 					expr2 := p.expr(0)
 					exprs << ast.RangeExpr{

vlib/v/parser/tests/match_range_dotdot_err.out

@@ -0,0 +1,7 @@
+vlib/v/parser/tests/match_range_dotdot_err.v:3:4: error: match only supports inclusive (`...`) ranges, not exclusive (`..`) 
+    1 | fn test_match() {
+    2 |     match 5 {
+    3 |         0..10 { '0-9' }
+      |          ~~
+    4 |         else { 'other' }
+    5 |     }

vlib/v/parser/tests/match_range_dotdot_err.vv

@@ -0,0 +1,6 @@
+fn test_match() {
+	match 5 {
+		0..10 { '0-9' }
+		else { 'other' }
+	}
+}

vlib/v/tests/match_test.v

@@ -63,19 +63,19 @@ fn test_match_integers() {
 }
 
 fn test_match_multiple() {
-	assert match 5 {
+	assert match 9 {
 		1, 2, 3 { '1-3' }
 		4, 5 { '4-5' }
-		6..9, 9 { '6-9' }
+		6...9 { '6-9' }
 		else { 'other' }
-	} == '4-5'
+	} == '6-9'
 }
 
 fn test_match_range() {
 	assert match `f` {
-		`0`..`9` { 'digit' }
+		`0`...`9` { 'digit' }
-		`A`..`Z` { 'uppercase' }
+		`A`...`Z` { 'uppercase' }
-		`a`..`z` { 'lowercase' }
+		`a`...`z` { 'lowercase' }
 		else { 'other' }
 	} == 'lowercase'
 }