parser: use Attr.arg field for [name: arg] (#6084)

doc/docs.md

@@ -2501,7 +2501,7 @@ On Unix-like platforms, the file can be run directly after making it executable
 
 V has several attributes that modify the behavior of functions and structs.
 
-An attribute is specified inside `[]` right before the function/struct declaration and applies only to the following definition.
+An attribute is specified inside `[]` right before a function/struct declaration and applies only to the following declaration.
 
 ```v
 // Calling this function will result in a deprecation warning

vlib/v/fmt/fmt.v

@@ -1115,18 +1115,7 @@ pub fn (mut f Fmt) or_expr(or_block ast.OrExpr) {
 
 fn (mut f Fmt) attrs(attrs []table.Attr) {
 	for attr in attrs {
-		f.write('[')
-		if attr.is_ctdefine {
-			f.write('if ')
-		}
-		if attr.is_string {
-			f.write("'")
-		}
-		f.write(attr.name)
-		if attr.is_string {
-			f.write("'")
-		}
-		f.writeln(']')
+		f.writeln('[$attr]')
 	}
 }
 
@@ -1139,7 +1128,7 @@ fn (mut f Fmt) inline_attrs(attrs []table.Attr) {
 		if i > 0 {
 			f.write(';')
 		}
-		f.write(attr.name)
+		f.write('$attr')
 	}
 	f.write(']')
 }

vlib/v/fmt/tests/attrs_keep.vv

@@ -1,5 +1,7 @@
 [inline]
 [if debug]
+[foo: bar]
+[deprecated: 'use bar() instead']
 fn keep_attributes() {
 	println('hi !')
 }

vlib/v/gen/comptime.v

@@ -88,6 +88,19 @@ fn (mut g Gen) comptime_call(node ast.ComptimeCall) {
 	}
 }
 
+fn cgen_attrs(attrs []table.Attr) []string {
+	mut res := []string{cap: attrs.len}
+	for attr in attrs {
+		// we currently don't quote 'arg' (otherwise we could just use `s := attr.str()`)
+		mut s := attr.name
+		if attr.arg.len > 0 {
+			s += ': $attr.arg'
+		}
+		res << 'tos_lit("$s")'
+	}
+	return res
+}
+
 fn (mut g Gen) comp_if(mut it ast.CompIf) {
 	if it.stmts.len == 0 && it.else_stmts.len == 0 {
 		return
@@ -175,10 +188,7 @@ fn (mut g Gen) comp_for(node ast.CompFor) {
 			if method.attrs.len == 0 {
 				g.writeln('\t${node.val_var}.attrs = __new_array_with_default(0, 0, sizeof(string), 0);')
 			} else {
-				mut attrs := []string{}
-				for attrib in method.attrs {
-					attrs << 'tos_lit("$attrib.name")'
-				}
+				attrs := cgen_attrs(method.attrs)
 				g.writeln('\t${node.val_var}.attrs = new_array_from_c_array($attrs.len, $attrs.len, sizeof(string), _MOV((string[$attrs.len]){' +
 					attrs.join(', ') + '}));')
 			}
@@ -210,10 +220,7 @@ fn (mut g Gen) comp_for(node ast.CompFor) {
 				if field.attrs.len == 0 {
 					g.writeln('\t${node.val_var}.attrs = __new_array_with_default(0, 0, sizeof(string), 0);')
 				} else {
-					mut attrs := []string{}
-					for attrib in field.attrs {
-						attrs << 'tos_lit("$attrib.name")'
-					}
+					attrs := cgen_attrs(field.attrs)
 					g.writeln('\t${node.val_var}.attrs = new_array_from_c_array($attrs.len, $attrs.len, sizeof(string), _MOV((string[$attrs.len]){' +
 						attrs.join(', ') + '}));')
 				}

vlib/v/gen/json.v

@@ -83,8 +83,8 @@ $enc_fn_dec {
 			}
 			mut name := field.name
 			for attr in field.attrs {
-				if attr.name.starts_with('json:') {
-					name = attr.name[5..]
+				if attr.name == 'json' {
+					name = attr.arg
 					break
 				}
 			}

vlib/v/parser/parser.v

@@ -432,7 +432,7 @@ pub fn (mut p Parser) top_stmt() ast.Stmt {
 				}
 			}
 			.lsbr {
-				// attrs are stores in `p.attrs()`
+				// attrs are stored in `p.attrs`
 				p.attributes()
 				continue
 			}
@@ -737,7 +737,9 @@ fn (mut p Parser) parse_attr() table.Attr {
 		is_ctdefine = true
 	}
 	mut name := ''
+	mut arg := ''
 	is_string := p.tok.kind == .string
+	mut is_string_arg := false
 	if is_string {
 		name = p.tok.lit
 		p.next()
@@ -749,12 +751,13 @@ fn (mut p Parser) parse_attr() table.Attr {
 			p.error_with_pos('please use `[trusted]` instead', p.tok.position())
 		}
 		if p.tok.kind == .colon {
-			name += ':'
 			p.next()
+			// `name: arg`
 			if p.tok.kind == .name {
-				name += p.check_name()
-			} else if p.tok.kind == .string {
-				name += p.tok.lit
+				arg = p.check_name()
+			} else if p.tok.kind == .string { // `name: 'arg'`
+				arg = p.tok.lit
+				is_string_arg = true
 				p.next()
 			}
 		}
@@ -763,6 +766,8 @@ fn (mut p Parser) parse_attr() table.Attr {
 		name: name
 		is_string: is_string
 		is_ctdefine: is_ctdefine
+		arg: arg
+		is_string_arg: is_string_arg
 	}
 }
 

vlib/v/table/attr.v

@@ -6,9 +6,38 @@ module table
 // e.g. `[unsafe]`
 pub struct Attr {
 pub:
-	name        string
-	is_string   bool // `['xxx']`
-	is_ctdefine bool // `[if flag]`
+	name        string // [name]
+	is_string   bool // ['name']
+	is_ctdefine bool // [if name]
+	arg         string // [name: arg]
+	is_string_arg bool // [name: 'arg']
+}
+
+// no square brackets
+pub fn (attr Attr) str() string {
+	mut s := ''
+	if attr.is_ctdefine {
+		s += 'if '
+	}
+	if attr.is_string {
+		s += "'$attr.name'"
+	}
+	else {
+		s += attr.name
+		if attr.arg.len > 0 {
+			s += ': '
+			if attr.is_string_arg {
+				mut a := attr.arg.replace('\\', '\\\\')
+				// FIXME: other escapes e.g. \r\n
+				a = a.replace("'", "\\'")
+				s += "'$a'"
+			}
+			else {
+				s += attr.arg
+			}
+		}
+	}
+	return s
 }
 
 pub fn (attrs []Attr) contains(str string) bool {