fmt: single line matches

vlib/v/fmt/fmt.v

@@ -67,7 +67,7 @@ fn (f mut Fmt) find_comment(line_nr int) {
 	}
 }
 */
-pub fn (f mut Fmt) write(s string) {
+pub fn (var f Fmt) write(s string) {
 	if f.indent > 0 && f.empty_line {
 		f.out.write(tabs[f.indent])
 		f.line_len += f.indent * 4
@@ -77,7 +77,7 @@ pub fn (f mut Fmt) write(s string) {
 	f.empty_line = false
 }
 
-pub fn (f mut Fmt) writeln(s string) {
+pub fn (var f Fmt) writeln(s string) {
 	if f.indent > 0 && f.empty_line {
 		// println(f.indent.str() + s)
 		f.out.write(tabs[f.indent])
@@ -87,7 +87,7 @@ pub fn (f mut Fmt) writeln(s string) {
 	f.line_len = 0
 }
 
-fn (f mut Fmt) mod(mod ast.Module) {
+fn (var f Fmt) mod(mod ast.Module) {
 	f.cur_mod = mod.name
 	if mod.is_skipped {
 		return
@@ -95,7 +95,7 @@ fn (f mut Fmt) mod(mod ast.Module) {
 	f.writeln('module $mod.name\n')
 }
 
-fn (f mut Fmt) imports(imports []ast.Import) {
+fn (var f Fmt) imports(imports []ast.Import) {
 	if f.did_imports || imports.len == 0 {
 		return
 	}
@@ -129,7 +129,7 @@ fn (f Fmt) imp_stmt_str(imp ast.Import) string {
 	return '${imp.mod}${imp_alias_suffix}'
 }
 
-fn (f mut Fmt) stmts(stmts []ast.Stmt) {
+fn (var f Fmt) stmts(stmts []ast.Stmt) {
 	f.indent++
 	for stmt in stmts {
 		f.stmt(stmt)
@@ -137,7 +137,7 @@ fn (f mut Fmt) stmts(stmts []ast.Stmt) {
 	f.indent--
 }
 
-fn (f mut Fmt) stmt(node ast.Stmt) {
+fn (var f Fmt) stmt(node ast.Stmt) {
 	match node {
 		ast.AssignStmt {
 			for i, ident in it.left {
@@ -178,12 +178,8 @@ fn (f mut Fmt) stmt(node ast.Stmt) {
 		}
 		ast.BranchStmt {
 			match it.tok.kind {
-				.key_break {
+				.key_break { f.writeln('break') }
-					f.writeln('break')
+				.key_continue { f.writeln('continue') }
-				}
-				.key_continue {
-					f.writeln('continue')
-				}
 				else {}
 			}
 		}
@@ -379,7 +375,7 @@ fn (f mut Fmt) stmt(node ast.Stmt) {
 	}
 }
 
-fn (f mut Fmt) type_decl(node ast.TypeDecl) {
+fn (var f Fmt) type_decl(node ast.TypeDecl) {
 	match node {
 		ast.AliasTypeDecl {
 			if it.is_pub {
@@ -406,7 +402,7 @@ fn (f mut Fmt) type_decl(node ast.TypeDecl) {
 	f.writeln('\n')
 }
 
-fn (f mut Fmt) struct_decl(node ast.StructDecl) {
+fn (var f Fmt) struct_decl(node ast.StructDecl) {
 	if node.is_pub {
 		f.write('pub ')
 	}
@@ -453,17 +449,17 @@ fn (f mut Fmt) struct_decl(node ast.StructDecl) {
 }
 
 fn (f &Fmt) type_to_str(t table.Type) string {
-	mut res := f.table.type_to_str(t)
+	var res := f.table.type_to_str(t)
 	// type_ptr => &type
 	if res.ends_with('_ptr') {
-		res = res[0 .. res.len-4]
+		res = res[0..res.len - 4]
 		start_pos := 2 * res.count('[]')
-		res = res[0 .. start_pos] + '&' + res[start_pos .. res.len]
+		res = res[0..start_pos] + '&' + res[start_pos..res.len]
 	}
 	return res.replace(f.cur_mod + '.', '')
 }
 
-fn (f mut Fmt) expr(node ast.Expr) {
+fn (var f Fmt) expr(node ast.Expr) {
 	match node {
 		ast.ArrayInit {
 			if it.exprs.len == 0 && it.typ != 0 && it.typ != table.void_type {
@@ -582,46 +578,7 @@ fn (f mut Fmt) expr(node ast.Expr) {
 			f.write('}')
 		}
 		ast.MatchExpr {
-			f.write('match ')
+			f.match_expr(it)
-			if it.is_mut {
-				f.write('var ')
-			}
-			f.expr(it.cond)
-			f.writeln(' {')
-			f.indent++
-			for i, branch in it.branches {
-				if branch.comment.text != '' {
-					f.comment(branch.comment)
-				}
-				if !branch.is_else {
-					// normal branch
-					for j, expr in branch.exprs {
-						f.expr(expr)
-						if j < branch.exprs.len - 1 {
-							f.write(', ')
-						}
-					}
-				} else {
-					// else branch
-					f.write('else')
-				}
-				if branch.stmts.len == 0 {
-					f.writeln(' {}')
-				} else {
-					// TODO single line branches
-					// if branch.stmts.len < 2 {
-					// f.write(' { ')
-					// } else {
-					f.writeln(' {')
-					// f.single_line_if = true
-					// }
-					f.stmts(branch.stmts)
-					// f.single_line_if = false
-					f.writeln('}')
-				}
-			}
-			f.indent--
-			f.write('}')
 		}
 		ast.None {
 			f.write('none')
@@ -737,7 +694,7 @@ fn (f mut Fmt) expr(node ast.Expr) {
 	}
 }
 
-fn (f mut Fmt) wrap_long_line() {
+fn (var f Fmt) wrap_long_line() {
 	if f.line_len > max_len {
 		if f.out.buf[f.out.buf.len - 1] == ` ` {
 			f.out.go_back(1)
@@ -747,7 +704,7 @@ fn (f mut Fmt) wrap_long_line() {
 	}
 }
 
-fn (f mut Fmt) call_args(args []ast.CallArg) {
+fn (var f Fmt) call_args(args []ast.CallArg) {
 	for i, arg in args {
 		if arg.is_mut {
 			f.write('mut ')
@@ -762,7 +719,7 @@ fn (f mut Fmt) call_args(args []ast.CallArg) {
 	}
 }
 
-fn (f mut Fmt) or_expr(or_block ast.OrExpr) {
+fn (var f Fmt) or_expr(or_block ast.OrExpr) {
 	if or_block.stmts.len > 0 {
 		f.writeln(' or {')
 		f.stmts(or_block.stmts)
@@ -770,7 +727,7 @@ fn (f mut Fmt) or_expr(or_block ast.OrExpr) {
 	}
 }
 
-fn (f mut Fmt) comment(node ast.Comment) {
+fn (var f Fmt) comment(node ast.Comment) {
 	if !node.text.contains('\n') {
 		is_separate_line := node.text.starts_with('|')
 		var s := if is_separate_line { node.text[1..] } else { node.text }
@@ -806,7 +763,7 @@ fn short_module(name string) string {
 	return vals[vals.len - 2] + '.' + vals[vals.len - 1]
 }
 
-fn (f mut Fmt) if_expr(it ast.IfExpr) {
+fn (var f Fmt) if_expr(it ast.IfExpr) {
 	single_line := it.branches.len == 2 && it.has_else && it.branches[0].stmts.len == 1 &&
 		it.branches[1].stmts.len == 1 && (it.is_expr || f.is_assign)
 	f.single_line_if = single_line
@@ -839,7 +796,7 @@ fn (f mut Fmt) if_expr(it ast.IfExpr) {
 	f.single_line_if = false
 }
 
-fn (f mut Fmt) call_expr(node ast.CallExpr) {
+fn (var f Fmt) call_expr(node ast.CallExpr) {
 	if node.is_method {
 		match node.left {
 			ast.Ident {
@@ -876,13 +833,77 @@ fn (f mut Fmt) call_expr(node ast.CallExpr) {
 	}
 }
 
-fn (f mut Fmt) mark_types_module_as_used(typ table.Type) {
+fn (var f Fmt) match_expr(it ast.MatchExpr) {
+	f.write('match ')
+	if it.is_mut {
+		f.write('var ')
+	}
+	f.expr(it.cond)
+	f.writeln(' {')
+	f.indent++
+	var single_line := true
+	for i, branch in it.branches {
+		if branch.stmts.len > 1 {
+			single_line = false
+			break
+		}
+	}
+	for i, branch in it.branches {
+		if branch.comment.text != '' {
+			f.comment(branch.comment)
+		}
+		if !branch.is_else {
+			// normal branch
+			for j, expr in branch.exprs {
+				f.expr(expr)
+				if j < branch.exprs.len - 1 {
+					f.write(', ')
+				}
+			}
+		} else {
+			// else branch
+			f.write('else')
+		}
+		if branch.stmts.len == 0 {
+			f.writeln(' {}')
+		} else {
+			if single_line {
+				f.write(' { ')
+			} else {
+				f.writeln(' {')
+			}
+			f.stmts(branch.stmts)
+			if single_line {
+				f.remove_new_line()
+				f.writeln(' }')
+			} else {
+				f.writeln('}')
+			}
+		}
+	}
+	f.indent--
+	f.write('}')
+}
+
+fn (var f Fmt) remove_new_line() {
+	var i := 0
+	for i = f.out.len - 1; i >= 0; i-- {
+		if !f.out.buf[i].is_space() {			// != `\n` {
+			break
+		}
+	}
+	f.out.go_back(f.out.len - i - 1)
+	f.empty_line = false
+	// f.writeln('sdf')
+}
+
+fn (var f Fmt) mark_types_module_as_used(typ table.Type) {
 	sym := f.table.get_type_symbol(typ)
 	f.mark_module_as_used(sym.name)
 }
 
 // `name` is a function (`foo.bar()`) or type (`foo.Bar{}`)
-fn (f mut Fmt) mark_module_as_used(name string) {
+fn (var f Fmt) mark_module_as_used(name string) {
 	if !name.contains('.') {
 		return
 	}

vlib/v/fmt/tests/match_expected.vv

@@ -1,12 +1,8 @@
 fn match_expr() {
 	a := 10
 	match a {
-		10 {
+		10 { println('10') }
-			println('10')
+		20 { println('20') }
-		}
-		20 {
-			println('20')
-		}
 		else {}
 	}
 }
@@ -14,14 +10,8 @@ fn match_expr() {
 fn match_expr_assignment() {
 	a := 20
 	b := match a {
-		10 {
+		10 { 10 }
-			10
+		5 { 5 }
-		}
+		else { 2 }
-		5 {
-			5
-		}
-		else {
-			2
-		}
 	}
 }

vlib/v/tests/match_test.v

@@ -9,59 +9,35 @@ pub fn (c Color) str() string {
 }
 
 fn test_match_integers() {
-	mut a := 3
+	var a := 3
-	mut b := 0
+	var b := 0
 	match a {
-		2 {
+		2 { println('two') }
-			println('two')
-		}
 		3 {
 			println('three')
 			b = 3
 		}
-		4 {
+		4 { println('four') }
-			println('four')
+		else { println('???') }
-		}
-		else {
-			println('???')
-		}
 	}
 	assert b == 3
 	assert match 2 {
-		1 {
+		1 { 2 }
-			2
+		2 { 3 }
-		}
+		else { 5 }
-		2 {
-			3
-		}
-		else {
-			5
-		}
 	} == 3
 	assert match 0 {
-		1 {
+		1 { 2 }
-			2
+		2 { 3 }
-		}
+		else { 5 }
-		2 {
-			3
-		}
-		else {
-			5
-		}
 	} == 5
 	assert match 1 {
-		else {
+		else { 5 }
-			5
-		}
 	} == 5
 	a = 0
 	match 2 {
-		0 {
+		0 { a = 1 }
-			a = 1
+		1 { a = 2 }
-		}
-		1 {
-			a = 2
-		}
 		else {
 			a = 3
 			println('a is $a')
@@ -70,9 +46,7 @@ fn test_match_integers() {
 	assert a == 3
 	a = 0
 	match 1 {
-		0 {
+		0 { a = 1 }
-			a = 1
-		}
 		1 {
 			a = 2
 			a = a + 2
@@ -83,22 +57,16 @@ fn test_match_integers() {
 	assert a == 6
 	a = 0
 	match 1 {
-		else {
+		else { a = -2 }
-			a = -2
-		}
 	}
 	assert a == -2
 }
 
 fn test_match_enums() {
-	mut b := Color.red
+	var b := Color.red
 	match b {
-		.red {
+		.red { b = .green }
-			b = .green
+		.green { b = .blue }
-		}
-		.green {
-			b = .blue
-		}
 		else {
 			println('b is ${b.str()}')
 			b = .red
@@ -106,9 +74,7 @@ fn test_match_enums() {
 	}
 	assert b == .green
 	match b {
-		.red {
+		.red { b = .green }
-			b = .green
-		}
 		else {
 			println('b is ${b.str()}')
 			b = .blue