vlib: add toml module + tests (#11964)

vlib/toml/ast/ast.v

@@ -0,0 +1,28 @@
+// Copyright (c) 2021 Lars Pontoppidan. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module ast
+
+import toml.input
+
+// Root represents the root structure of any parsed TOML text snippet or file.
+[heap]
+pub struct Root {
+pub:
+	input input.Config // User input configuration
+pub mut:
+	table Node
+	// errors           []errors.Error    // all the checker errors in the file
+}
+
+pub fn (r Root) str() string {
+	mut s := typeof(r).name + '{\n'
+	s += '  input:  $r.input\n'
+	s += '  table:  $r.table\n'
+	s += '}'
+	return s
+}
+
+pub fn (r Root) to_json() string {
+	return r.table.to_json()
+}

vlib/toml/ast/types.v

@@ -0,0 +1,241 @@
+// Copyright (c) 2021 Lars Pontoppidan. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module ast
+
+import toml.token
+
+// Key is a sumtype representing all types of keys that
+// can be found in a TOML document.
+pub type Key = Bare | Bool | Null | Number | Quoted
+
+pub fn (k Key) str() string {
+	return k.text
+}
+
+// Node is a sumtype representing all possible value types
+// found in a TOML document.
+pub type Node = Bool | Date | DateTime | Null | Number | Quoted | Time | []Node | map[string]Node
+
+pub fn (v Node) to_json() string {
+	match v {
+		Quoted, Date, DateTime, Time {
+			return '"$v.text"'
+		}
+		Bool, Null, Number {
+			return v.text
+		}
+		map[string]Node {
+			mut str := '{'
+			for key, val in v {
+				str += ' "$key": $val.to_json(),'
+			}
+			str = str.trim_right(',')
+			str += ' }'
+			return str
+		}
+		[]Node {
+			mut str := '['
+			for val in v {
+				str += ' $val.to_json(),'
+			}
+			str = str.trim_right(',')
+			str += ' ]'
+			return str
+		}
+	}
+}
+
+// DateTimeType is a sumtype representing all possible date types
+// found in a TOML document.
+pub type DateTimeType = Date | DateTime | Time
+
+pub fn (dtt DateTimeType) str() string {
+	return dtt.text
+}
+
+// value queries a value from the map.
+// `key` should be in "dotted" form e.g.: `"a.b.c.d"`
+pub fn (v map[string]Node) value(key string) &Node {
+	null := &Node(Null{})
+	key_split := key.split('.')
+	// util.printdbg(@MOD + '.' + @STRUCT + '.' + @FN, ' retreiving value at "$key"')
+	if key_split[0] in v.keys() {
+		value := v[key_split[0]] or {
+			return null
+			// TODO return error(@MOD + '.' + @STRUCT + '.' + @FN + ' key "$key" does not exist')
+		}
+		// `match` isn't currently very suitable for these types of sum type constructs...
+		if value is map[string]Node {
+			m := (value as map[string]Node)
+			next_key := key_split[1..].join('.')
+			if next_key == '' {
+				return &value
+			}
+			return m.value(next_key)
+		}
+		return &value
+	}
+	return null
+	// TODO return error(@MOD + '.' + @STRUCT + '.' + @FN + ' key "$key" does not exist')
+}
+
+// value queries a value from the map.
+pub fn (v map[string]Node) exists(key string) bool {
+	key_split := key.split('.')
+	if key_split[0] in v.keys() {
+		value := v[key_split[0]] or { return false }
+		// `match` isn't currently very suitable for these types of sum type constructs...
+		if value is map[string]Node {
+			m := (value as map[string]Node)
+			next_key := key_split[1..].join('.')
+			if next_key == '' {
+				return true
+			}
+			return m.exists(next_key)
+		}
+		return true
+	}
+	return false
+}
+
+pub struct Comment {
+pub:
+	text string
+	pos  token.Position
+}
+
+pub fn (c Comment) str() string {
+	mut s := typeof(c).name + '{\n'
+	s += '  text:  \'$c.text\'\n'
+	s += '  pos:  $c.pos\n'
+	s += '}'
+	return s
+}
+
+// Null is used in sumtype checks as a "default" value when nothing else is possible.
+pub struct Null {
+pub:
+	text string
+	pos  token.Position
+}
+
+pub fn (n Null) str() string {
+	return n.text
+}
+
+pub struct Quoted {
+pub:
+	text string
+	pos  token.Position
+}
+
+pub fn (q Quoted) str() string {
+	mut str := typeof(q).name + '{\n'
+	str += '  text:  \'$q.text\'\n'
+	str += '  pos:  $q.pos\n'
+	str += '}'
+	return str
+}
+
+pub struct Bare {
+pub:
+	text string
+	pos  token.Position
+}
+
+pub fn (b Bare) str() string {
+	mut str := typeof(b).name + '{\n'
+	str += '  text:  \'$b.text\'\n'
+	str += '  pos:  $b.pos\n'
+	str += '}'
+	return str
+}
+
+pub struct Bool {
+pub:
+	text string
+	pos  token.Position
+}
+
+pub fn (b Bool) str() string {
+	mut str := typeof(b).name + '{\n'
+	str += '  text:  \'$b.text\'\n'
+	str += '  pos:  $b.pos\n'
+	str += '}'
+	return str
+}
+
+pub struct Number {
+pub:
+	text string
+	pos  token.Position
+}
+
+pub fn (n Number) str() string {
+	mut str := typeof(n).name + '{\n'
+	str += '  text:  \'$n.text\'\n'
+	str += '  pos:  $n.pos\n'
+	str += '}'
+	return str
+}
+
+pub struct Date {
+pub:
+	text string
+	pos  token.Position
+}
+
+pub fn (d Date) str() string {
+	mut str := typeof(d).name + '{\n'
+	str += '  text:  \'$d.text\'\n'
+	str += '  pos:  $d.pos\n'
+	str += '}'
+	return str
+}
+
+pub struct Time {
+pub:
+	text   string
+	offset int
+	pos    token.Position
+}
+
+pub fn (t Time) str() string {
+	mut str := typeof(t).name + '{\n'
+	str += '  text:  \'$t.text\'\n'
+	str += '  offset:  \'$t.offset\'\n'
+	str += '  pos:  $t.pos\n'
+	str += '}'
+	return str
+}
+
+pub struct DateTime {
+pub:
+	text string
+	pos  token.Position
+	date Date
+	time Time
+}
+
+pub fn (dt DateTime) str() string {
+	mut str := typeof(dt).name + '{\n'
+	str += '  text:  \'$dt.text\'\n'
+	str += '  date:  \'$dt.date\'\n'
+	str += '  time:  \'$dt.time\'\n'
+	str += '  pos:  $dt.pos\n'
+	str += '}'
+	return str
+}
+
+pub struct EOF {
+pub:
+	pos token.Position
+}
+
+pub fn (e EOF) str() string {
+	mut str := typeof(e).name + '{\n'
+	str += '  pos:  $e.pos\n'
+	str += '}'
+	return str
+}

vlib/toml/ast/walker/walker.v

@@ -0,0 +1,37 @@
+module walker
+
+import toml.ast
+
+// Visitor defines a visit method which is invoked by the walker in each node it encounters.
+pub interface Visitor {
+	visit(node &ast.Node) ?
+}
+
+pub type InspectorFn = fn (node &ast.Node, data voidptr) ?
+
+struct Inspector {
+	inspector_callback InspectorFn
+mut:
+	data voidptr
+}
+
+pub fn (i &Inspector) visit(node &ast.Node) ? {
+	i.inspector_callback(node, i.data) or { return err }
+}
+
+// inspect traverses and checks the AST node on a depth-first order and based on the data given
+pub fn inspect(node &ast.Node, data voidptr, inspector_callback InspectorFn) ? {
+	walk(Inspector{inspector_callback, data}, node) ?
+}
+
+// walk traverses the AST using the given visitor
+pub fn walk(visitor Visitor, node &ast.Node) ? {
+	if node is map[string]ast.Node {
+		n := node as map[string]ast.Node
+		for _, nn in n {
+			walk(visitor, &nn) ?
+		}
+	} else {
+		visitor.visit(node) ?
+	}
+}