Fix coveralls (#136)

* Rewrite `TomlTree` encoding
* Introduce `TomlTree.WriteTo`

.travis.yml

@@ -1,8 +1,9 @@
+sudo: false
 language: go
 go:
-  - 1.5.4
   - 1.6.4
-  - 1.7.4
+  - 1.7.5
+  - 1.8
   - tip
 matrix:
   allow_failures:
@@ -14,5 +15,7 @@ before_install:
   - go get github.com/axw/gocov/gocov
   - go get github.com/mattn/goveralls
   - if ! go get code.google.com/p/go.tools/cmd/cover; then go get golang.org/x/tools/cmd/cover; fi
+branches:
+  only: [master]
 after_success:
-  - $HOME/gopath/bin/goveralls -service=travis-ci
+  - $HOME/gopath/bin/goveralls -service=travis-ci -coverprofile=coverage.out -repotoken $COVERALLS_TOKEN

LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2013 - 2016 Thomas Pelletier, Eric Anderton
+Copyright (c) 2013 - 2017 Thomas Pelletier, Eric Anderton
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -19,4 +19,3 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
-

README.md

@@ -6,7 +6,7 @@ This library supports TOML version
 [v0.4.0](https://github.com/toml-lang/toml/blob/master/versions/en/toml-v0.4.0.md)
 
 [![GoDoc](https://godoc.org/github.com/pelletier/go-toml?status.svg)](http://godoc.org/github.com/pelletier/go-toml)
-[![License](https://img.shields.io/badge/license-MIT-blue.svg)](https://github.com/goadesign/goa/blob/master/LICENSE)
+[![license](https://img.shields.io/github/license/pelletier/go-toml.svg)](https://github.com/pelletier/go-toml/blob/master/LICENSE)
 [![Build Status](https://travis-ci.org/pelletier/go-toml.svg?branch=master)](https://travis-ci.org/pelletier/go-toml)
 [![Coverage Status](https://coveralls.io/repos/github/pelletier/go-toml/badge.svg?branch=master)](https://coveralls.io/github/pelletier/go-toml?branch=master)
 [![Go Report Card](https://goreportcard.com/badge/github.com/pelletier/go-toml)](https://goreportcard.com/report/github.com/pelletier/go-toml)
@@ -96,7 +96,7 @@ Go-toml provides two handy command line tools:
 * `tomljson`: Reads a TOML file and outputs its JSON representation.
 
     ```
-    go install github.com/pelletier/go-toml/cmd/tomjson
+    go install github.com/pelletier/go-toml/cmd/tomljson
     tomljson --help
     ```
 

doc.go

@@ -22,8 +22,8 @@
 // After parsing TOML data with Load() or LoadFile(), use the Has() and Get()
 // methods on the returned TomlTree, to find your way through the document data.
 //
-//   if tree.Has('foo') {
-//     fmt.Prinln("foo is: %v", tree.Get('foo'))
+//   if tree.Has("foo") {
+//     fmt.Println("foo is:", tree.Get("foo"))
 //   }
 //
 // Working with Paths
@@ -44,10 +44,10 @@
 // it avoids having to parse the passed key for '.' delimiters.
 //
 //   // looks for a key named 'baz', within struct 'bar', within struct 'foo'
-//   tree.HasPath(string{}{"foo","bar","baz"})
+//   tree.HasPath([]string{"foo","bar","baz"})
 //
 //   // returns the key at this path, if it is there
-//   tree.GetPath(string{}{"foo","bar","baz"})
+//   tree.GetPath([]string{"foo","bar","baz"})
 //
 // Note that this is distinct from the heavyweight query syntax supported by
 // TomlTree.Query() and the Query() struct (see below).

keysparsing.go

@@ -4,6 +4,7 @@ package toml
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"unicode"
 )
@@ -47,7 +48,7 @@ func parseKey(key string) ([]string, error) {
 			} else {
 				if !wasInQuotes {
 					if buffer.Len() == 0 {
-						return nil, fmt.Errorf("empty key group")
+						return nil, errors.New("empty table key")
 					}
 					groups = append(groups, buffer.String())
 					buffer.Reset()
@@ -67,23 +68,23 @@ func parseKey(key string) ([]string, error) {
 				return nil, fmt.Errorf("invalid bare character: %c", char)
 			}
 			if !inQuotes && expectDot {
-				return nil, fmt.Errorf("what?")
+				return nil, errors.New("what?")
 			}
 			buffer.WriteRune(char)
 			expectDot = false
 		}
 	}
 	if inQuotes {
-		return nil, fmt.Errorf("mismatched quotes")
+		return nil, errors.New("mismatched quotes")
 	}
 	if escapeNext {
-		return nil, fmt.Errorf("unfinished escape sequence")
+		return nil, errors.New("unfinished escape sequence")
 	}
 	if buffer.Len() > 0 {
 		groups = append(groups, buffer.String())
 	}
 	if len(groups) == 0 {
-		return nil, fmt.Errorf("empty key")
+		return nil, errors.New("empty key")
 	}
 	return groups, nil
 }

lexer.go

@@ -36,7 +36,7 @@ type tomlLexer struct {
 // Basic read operations on input
 
 func (l *tomlLexer) read() rune {
-	r, err := l.input.ReadRune()
+	r, _, err := l.input.ReadRune()
 	if err != nil {
 		panic(err)
 	}
@@ -89,7 +89,7 @@ func (l *tomlLexer) emit(t tokenType) {
 }
 
 func (l *tomlLexer) peek() rune {
-	r, err := l.input.ReadRune()
+	r, _, err := l.input.ReadRune()
 	if err != nil {
 		panic(err)
 	}
@@ -99,7 +99,7 @@ func (l *tomlLexer) peek() rune {
 
 func (l *tomlLexer) follow(next string) bool {
 	for _, expectedRune := range next {
-		r, err := l.input.ReadRune()
+		r, _, err := l.input.ReadRune()
 		defer l.input.UnreadRune()
 		if err != nil {
 			panic(err)
@@ -129,9 +129,9 @@ func (l *tomlLexer) lexVoid() tomlLexStateFn {
 		next := l.peek()
 		switch next {
 		case '[':
-			return l.lexKeyGroup
+			return l.lexTableKey
 		case '#':
-			return l.lexComment
+			return l.lexComment(l.lexVoid)
 		case '=':
 			return l.lexEqual
 		case '\r':
@@ -182,7 +182,7 @@ func (l *tomlLexer) lexRvalue() tomlLexStateFn {
 		case '}':
 			return l.lexRightCurlyBrace
 		case '#':
-			return l.lexComment
+			return l.lexComment(l.lexRvalue)
 		case '"':
 			return l.lexString
 		case '\'':
@@ -219,7 +219,7 @@ func (l *tomlLexer) lexRvalue() tomlLexStateFn {
 			break
 		}
 
-		possibleDate := string(l.input.Peek(35))
+		possibleDate := string(l.input.PeekRunes(35))
 		dateMatch := dateRegexp.FindString(possibleDate)
 		if dateMatch != "" {
 			l.fastForward(len(dateMatch))
@@ -309,15 +309,17 @@ func (l *tomlLexer) lexKey() tomlLexStateFn {
 	return l.lexVoid
 }
 
-func (l *tomlLexer) lexComment() tomlLexStateFn {
-	for next := l.peek(); next != '\n' && next != eof; next = l.peek() {
-		if next == '\r' && l.follow("\r\n") {
-			break
+func (l *tomlLexer) lexComment(previousState tomlLexStateFn) tomlLexStateFn {
+	return func() tomlLexStateFn {
+		for next := l.peek(); next != '\n' && next != eof; next = l.peek() {
+			if next == '\r' && l.follow("\r\n") {
+				break
+			}
+			l.next()
 		}
-		l.next()
+		l.ignore()
+		return previousState
 	}
-	l.ignore()
-	return l.lexVoid
 }
 
 func (l *tomlLexer) lexLeftBracket() tomlLexStateFn {
@@ -516,21 +518,21 @@ func (l *tomlLexer) lexString() tomlLexStateFn {
 	return l.lexRvalue
 }
 
-func (l *tomlLexer) lexKeyGroup() tomlLexStateFn {
+func (l *tomlLexer) lexTableKey() tomlLexStateFn {
 	l.next()
 
 	if l.peek() == '[' {
-		// token '[[' signifies an array of anonymous key groups
+		// token '[[' signifies an array of tables
 		l.next()
 		l.emit(tokenDoubleLeftBracket)
-		return l.lexInsideKeyGroupArray
+		return l.lexInsideTableArrayKey
 	}
-	// vanilla key group
+	// vanilla table key
 	l.emit(tokenLeftBracket)
-	return l.lexInsideKeyGroup
+	return l.lexInsideTableKey
 }
 
-func (l *tomlLexer) lexInsideKeyGroupArray() tomlLexStateFn {
+func (l *tomlLexer) lexInsideTableArrayKey() tomlLexStateFn {
 	for r := l.peek(); r != eof; r = l.peek() {
 		switch r {
 		case ']':
@@ -545,15 +547,15 @@ func (l *tomlLexer) lexInsideKeyGroupArray() tomlLexStateFn {
 			l.emit(tokenDoubleRightBracket)
 			return l.lexVoid
 		case '[':
-			return l.errorf("group name cannot contain ']'")
+			return l.errorf("table array key cannot contain ']'")
 		default:
 			l.next()
 		}
 	}
-	return l.errorf("unclosed key group array")
+	return l.errorf("unclosed table array key")
 }
 
-func (l *tomlLexer) lexInsideKeyGroup() tomlLexStateFn {
+func (l *tomlLexer) lexInsideTableKey() tomlLexStateFn {
 	for r := l.peek(); r != eof; r = l.peek() {
 		switch r {
 		case ']':
@@ -564,12 +566,12 @@ func (l *tomlLexer) lexInsideKeyGroup() tomlLexStateFn {
 			l.emit(tokenRightBracket)
 			return l.lexVoid
 		case '[':
-			return l.errorf("group name cannot contain ']'")
+			return l.errorf("table key cannot contain ']'")
 		default:
 			l.next()
 		}
 	}
-	return l.errorf("unclosed key group")
+	return l.errorf("unclosed table key")
 }
 
 func (l *tomlLexer) lexRightBracket() tomlLexStateFn {

lexer_test.go

@@ -56,7 +56,7 @@ func TestNestedQuotedUnicodeKeyGroup(t *testing.T) {
 func TestUnclosedKeyGroup(t *testing.T) {
 	testFlow(t, "[hello world", []token{
 		{Position{1, 1}, tokenLeftBracket, "["},
-		{Position{1, 2}, tokenError, "unclosed key group"},
+		{Position{1, 2}, tokenError, "unclosed table key"},
 	})
 }
 
@@ -264,6 +264,24 @@ func TestMultilineArrayComments(t *testing.T) {
 	})
 }
 
+func TestNestedArraysComment(t *testing.T) {
+	toml := `
+someArray = [
+# does not work
+["entry1"]
+]`
+	testFlow(t, toml, []token{
+		{Position{2, 1}, tokenKey, "someArray"},
+		{Position{2, 11}, tokenEqual, "="},
+		{Position{2, 13}, tokenLeftBracket, "["},
+		{Position{4, 1}, tokenLeftBracket, "["},
+		{Position{4, 3}, tokenString, "entry1"},
+		{Position{4, 10}, tokenRightBracket, "]"},
+		{Position{5, 1}, tokenRightBracket, "]"},
+		{Position{5, 2}, tokenEOF, ""},
+	})
+}
+
 func TestKeyEqualArrayBools(t *testing.T) {
 	testFlow(t, "foo = [true, false, true]", []token{
 		{Position{1, 1}, tokenKey, "foo"},

parser.go

@@ -3,6 +3,7 @@
 package toml
 
 import (
+	"errors"
 	"fmt"
 	"reflect"
 	"regexp"
@@ -15,8 +16,8 @@ type tomlParser struct {
 	flow          chan token
 	tree          *TomlTree
 	tokensBuffer  []token
-	currentGroup  []string
-	seenGroupKeys []string
+	currentTable  []string
+	seenTableKeys []string
 }
 
 type tomlParserStateFn func() tomlParserStateFn
@@ -95,13 +96,13 @@ func (p *tomlParser) parseGroupArray() tomlParserStateFn {
 	startToken := p.getToken() // discard the [[
 	key := p.getToken()
 	if key.typ != tokenKeyGroupArray {
-		p.raiseError(key, "unexpected token %s, was expecting a key group array", key)
+		p.raiseError(key, "unexpected token %s, was expecting a table array key", key)
 	}
 
-	// get or create group array element at the indicated part in the path
+	// get or create table array element at the indicated part in the path
 	keys, err := parseKey(key.val)
 	if err != nil {
-		p.raiseError(key, "invalid group array key: %s", err)
+		p.raiseError(key, "invalid table array key: %s", err)
 	}
 	p.tree.createSubTree(keys[:len(keys)-1], startToken.Position) // create parent entries
 	destTree := p.tree.GetPath(keys)
@@ -111,32 +112,32 @@ func (p *tomlParser) parseGroupArray() tomlParserStateFn {
 	} else if target, ok := destTree.([]*TomlTree); ok && target != nil {
 		array = destTree.([]*TomlTree)
 	} else {
-		p.raiseError(key, "key %s is already assigned and not of type group array", key)
+		p.raiseError(key, "key %s is already assigned and not of type table array", key)
 	}
-	p.currentGroup = keys
+	p.currentTable = keys
 
-	// add a new tree to the end of the group array
+	// add a new tree to the end of the table array
 	newTree := newTomlTree()
 	newTree.position = startToken.Position
 	array = append(array, newTree)
-	p.tree.SetPath(p.currentGroup, array)
+	p.tree.SetPath(p.currentTable, array)
 
-	// remove all keys that were children of this group array
+	// remove all keys that were children of this table array
 	prefix := key.val + "."
 	found := false
-	for ii := 0; ii < len(p.seenGroupKeys); {
-		groupKey := p.seenGroupKeys[ii]
-		if strings.HasPrefix(groupKey, prefix) {
-			p.seenGroupKeys = append(p.seenGroupKeys[:ii], p.seenGroupKeys[ii+1:]...)
+	for ii := 0; ii < len(p.seenTableKeys); {
+		tableKey := p.seenTableKeys[ii]
+		if strings.HasPrefix(tableKey, prefix) {
+			p.seenTableKeys = append(p.seenTableKeys[:ii], p.seenTableKeys[ii+1:]...)
 		} else {
-			found = (groupKey == key.val)
+			found = (tableKey == key.val)
 			ii++
 		}
 	}
 
 	// keep this key name from use by other kinds of assignments
 	if !found {
-		p.seenGroupKeys = append(p.seenGroupKeys, key.val)
+		p.seenTableKeys = append(p.seenTableKeys, key.val)
 	}
 
 	// move to next parser state
@@ -148,24 +149,24 @@ func (p *tomlParser) parseGroup() tomlParserStateFn {
 	startToken := p.getToken() // discard the [
 	key := p.getToken()
 	if key.typ != tokenKeyGroup {
-		p.raiseError(key, "unexpected token %s, was expecting a key group", key)
+		p.raiseError(key, "unexpected token %s, was expecting a table key", key)
 	}
-	for _, item := range p.seenGroupKeys {
+	for _, item := range p.seenTableKeys {
 		if item == key.val {
 			p.raiseError(key, "duplicated tables")
 		}
 	}
 
-	p.seenGroupKeys = append(p.seenGroupKeys, key.val)
+	p.seenTableKeys = append(p.seenTableKeys, key.val)
 	keys, err := parseKey(key.val)
 	if err != nil {
-		p.raiseError(key, "invalid group array key: %s", err)
+		p.raiseError(key, "invalid table array key: %s", err)
 	}
 	if err := p.tree.createSubTree(keys, startToken.Position); err != nil {
 		p.raiseError(key, "%s", err)
 	}
 	p.assume(tokenRightBracket)
-	p.currentGroup = keys
+	p.currentTable = keys
 	return p.parseStart
 }
 
@@ -174,26 +175,26 @@ func (p *tomlParser) parseAssign() tomlParserStateFn {
 	p.assume(tokenEqual)
 
 	value := p.parseRvalue()
-	var groupKey []string
-	if len(p.currentGroup) > 0 {
-		groupKey = p.currentGroup
+	var tableKey []string
+	if len(p.currentTable) > 0 {
+		tableKey = p.currentTable
 	} else {
-		groupKey = []string{}
+		tableKey = []string{}
 	}
 
-	// find the group to assign, looking out for arrays of groups
+	// find the table to assign, looking out for arrays of tables
 	var targetNode *TomlTree
-	switch node := p.tree.GetPath(groupKey).(type) {
+	switch node := p.tree.GetPath(tableKey).(type) {
 	case []*TomlTree:
 		targetNode = node[len(node)-1]
 	case *TomlTree:
 		targetNode = node
 	default:
-		p.raiseError(key, "Unknown group type for path: %s",
-			strings.Join(groupKey, "."))
+		p.raiseError(key, "Unknown table type for path: %s",
+			strings.Join(tableKey, "."))
 	}
 
-	// assign value to the found group
+	// assign value to the found table
 	keyVals, err := parseKey(key.val)
 	if err != nil {
 		p.raiseError(key, "%s", err)
@@ -203,7 +204,7 @@ func (p *tomlParser) parseAssign() tomlParserStateFn {
 	}
 	keyVal := keyVals[0]
 	localKey := []string{keyVal}
-	finalKey := append(groupKey, keyVal)
+	finalKey := append(tableKey, keyVal)
 	if targetNode.GetPath(localKey) != nil {
 		p.raiseError(key, "The following key was defined twice: %s",
 			strings.Join(finalKey, "."))
@@ -224,7 +225,7 @@ var numberUnderscoreInvalidRegexp *regexp.Regexp
 
 func cleanupNumberToken(value string) (string, error) {
 	if numberUnderscoreInvalidRegexp.MatchString(value) {
-		return "", fmt.Errorf("invalid use of _ in number")
+		return "", errors.New("invalid use of _ in number")
 	}
 	cleanedVal := strings.Replace(value, "_", "", -1)
 	return cleanedVal, nil
@@ -380,8 +381,8 @@ func parseToml(flow chan token) *TomlTree {
 		flow:          flow,
 		tree:          result,
 		tokensBuffer:  make([]token, 0),
-		currentGroup:  make([]string, 0),
-		seenGroupKeys: make([]string, 0),
+		currentTable:  make([]string, 0),
+		seenTableKeys: make([]string, 0),
 	}
 	parser.run()
 	return result

parser_test.go

@@ -283,6 +283,17 @@ func TestArrayNested(t *testing.T) {
 	})
 }
 
+func TestNestedArrayComment(t *testing.T) {
+	tree, err := Load(`
+someArray = [
+# does not work
+["entry1"]
+]`)
+	assertTree(t, tree, err, map[string]interface{}{
+		"someArray": [][]string{{"entry1"}},
+	})
+}
+
 func TestNestedEmptyArrays(t *testing.T) {
 	tree, err := Load("a = [[[]]]")
 	assertTree(t, tree, err, map[string]interface{}{
@@ -456,7 +467,7 @@ func TestDuplicateKeys(t *testing.T) {
 
 func TestEmptyIntermediateTable(t *testing.T) {
 	_, err := Load("[foo..bar]")
-	if err.Error() != "(1, 2): invalid group array key: empty key group" {
+	if err.Error() != "(1, 2): invalid table array key: empty table key" {
 		t.Error("Bad error message:", err.Error())
 	}
 }
@@ -580,12 +591,12 @@ func TestParseKeyGroupArray(t *testing.T) {
 
 func TestParseKeyGroupArrayUnfinished(t *testing.T) {
 	_, err := Load("[[foo.bar]\na = 42")
-	if err.Error() != "(1, 10): was expecting token [[, but got unclosed key group array instead" {
+	if err.Error() != "(1, 10): was expecting token [[, but got unclosed table array key instead" {
 		t.Error("Bad error message:", err.Error())
 	}
 
 	_, err = Load("[[foo.[bar]\na = 42")
-	if err.Error() != "(1, 3): unexpected token group name cannot contain ']', was expecting a key group array" {
+	if err.Error() != "(1, 3): unexpected token table array key cannot contain ']', was expecting a table array key" {
 		t.Error("Bad error message:", err.Error())
 	}
 }
@@ -622,22 +633,13 @@ func TestParseKeyGroupArraySpec(t *testing.T) {
 	})
 }
 
-func TestToTomlValue(t *testing.T) {
+func TestTomlValueStringRepresentation(t *testing.T) {
 	for idx, item := range []struct {
 		Value  interface{}
 		Expect string
 	}{
-		{int(1), "1"},
-		{int8(2), "2"},
-		{int16(3), "3"},
-		{int32(4), "4"},
 		{int64(12345), "12345"},
-		{uint(10), "10"},
-		{uint8(20), "20"},
-		{uint16(30), "30"},
-		{uint32(40), "40"},
 		{uint64(50), "50"},
-		{float32(12.456), "12.456"},
 		{float64(123.45), "123.45"},
 		{bool(true), "true"},
 		{"hello world", "\"hello world\""},
@@ -646,42 +648,22 @@ func TestToTomlValue(t *testing.T) {
 		{time.Date(1979, time.May, 27, 7, 32, 0, 0, time.UTC),
 			"1979-05-27T07:32:00Z"},
 		{[]interface{}{"gamma", "delta"},
-			"[\n  \"gamma\",\n  \"delta\",\n]"},
+			"[\"gamma\",\"delta\"]"},
 		{nil, ""},
 	} {
-		result := toTomlValue(item.Value, 0)
+		result, err := tomlValueStringRepresentation(item.Value)
+		if err != nil {
+			t.Errorf("Test %d - unexpected error: %s", idx, err)
+		}
 		if result != item.Expect {
 			t.Errorf("Test %d - got '%s', expected '%s'", idx, result, item.Expect)
 		}
 	}
 }
 
-func TestToString(t *testing.T) {
-	tree, err := Load("[foo]\n\n[[foo.bar]]\na = 42\n\n[[foo.bar]]\na = 69\n")
-	if err != nil {
-		t.Errorf("Test failed to parse: %v", err)
-		return
-	}
-	result := tree.ToString()
-	expected := "\n[foo]\n\n  [[foo.bar]]\n    a = 42\n\n  [[foo.bar]]\n    a = 69\n"
-	if result != expected {
-		t.Errorf("Expected got '%s', expected '%s'", result, expected)
-	}
-}
-
 func TestToStringMapStringString(t *testing.T) {
-	in := map[string]interface{}{"m": map[string]string{"v": "abc"}}
-	want := "\n[m]\n  v = \"abc\"\n"
-	tree := TreeFromMap(in)
-	got := tree.String()
-
-	if got != want {
-		t.Errorf("want:\n%q\ngot:\n%q", want, got)
-	}
-}
-
-func TestToStringMapInterfaceInterface(t *testing.T) {
-	in := map[string]interface{}{"m": map[interface{}]interface{}{"v": "abc"}}
+	in := map[string]interface{}{"m": TreeFromMap(map[string]interface{}{
+		"v": &tomlValue{"abc", Position{0, 0}}})}
 	want := "\n[m]\n  v = \"abc\"\n"
 	tree := TreeFromMap(in)
 	got := tree.String()
@@ -753,13 +735,13 @@ func TestNestedTreePosition(t *testing.T) {
 }
 
 func TestInvalidGroupArray(t *testing.T) {
-	_, err := Load("[key#group]\nanswer = 42")
+	_, err := Load("[table#key]\nanswer = 42")
 	if err == nil {
 		t.Error("Should error")
 	}
 
 	_, err = Load("[foo.[bar]\na = 42")
-	if err.Error() != "(1, 2): unexpected token group name cannot contain ']', was expecting a key group" {
+	if err.Error() != "(1, 2): unexpected token table key cannot contain ']', was expecting a table key" {
 		t.Error("Bad error message:", err.Error())
 	}
 }
@@ -773,7 +755,7 @@ func TestDoubleEqual(t *testing.T) {
 
 func TestGroupArrayReassign(t *testing.T) {
 	_, err := Load("[hello]\n[[hello]]")
-	if err.Error() != "(2, 3): key \"hello\" is already assigned and not of type group array" {
+	if err.Error() != "(2, 3): key \"hello\" is already assigned and not of type table array" {
 		t.Error("Bad error message:", err.Error())
 	}
 }

test.sh

@@ -19,6 +19,9 @@ function git_clone() {
   popd
 }
 
+# Run go vet
+go vet ./...
+
 go get github.com/pelletier/go-buffruneio
 go get github.com/davecgh/go-spew/spew
 
@@ -38,8 +41,8 @@ cp -R cmd/* src/github.com/pelletier/go-toml/cmd
 go build -o test_program_bin src/github.com/pelletier/go-toml/cmd/test_program.go
 
 # Run basic unit tests
-go test github.com/pelletier/go-toml \
-        github.com/pelletier/go-toml/cmd/tomljson
+go test github.com/pelletier/go-toml -v -covermode=count -coverprofile=coverage.out
+go test github.com/pelletier/go-toml/cmd/tomljson
 
 # run the entire BurntSushi test suite
 if [[ $# -eq 0 ]] ; then

toml.go

@@ -10,13 +10,13 @@ import (
 )
 
 type tomlValue struct {
-	value    interface{}
+	value    interface{} // string, int64, uint64, float64, bool, time.Time, [] of any of this list
 	position Position
 }
 
 // TomlTree is the result of the parsing of a TOML file.
 type TomlTree struct {
-	values   map[string]interface{}
+	values   map[string]interface{} // string -> *tomlValue, *TomlTree, []*TomlTree
 	position Position
 }
 

tomltree_conversions.go

@@ -1,207 +0,0 @@
-package toml
-
-// Tools to convert a TomlTree to different representations
-
-import (
-	"fmt"
-	"strconv"
-	"strings"
-	"time"
-)
-
-// encodes a string to a TOML-compliant string value
-func encodeTomlString(value string) string {
-	result := ""
-	for _, rr := range value {
-		intRr := uint16(rr)
-		switch rr {
-		case '\b':
-			result += "\\b"
-		case '\t':
-			result += "\\t"
-		case '\n':
-			result += "\\n"
-		case '\f':
-			result += "\\f"
-		case '\r':
-			result += "\\r"
-		case '"':
-			result += "\\\""
-		case '\\':
-			result += "\\\\"
-		default:
-			if intRr < 0x001F {
-				result += fmt.Sprintf("\\u%0.4X", intRr)
-			} else {
-				result += string(rr)
-			}
-		}
-	}
-	return result
-}
-
-// Value print support function for ToString()
-// Outputs the TOML compliant string representation of a value
-func toTomlValue(item interface{}, indent int) string {
-	tab := strings.Repeat(" ", indent)
-	switch value := item.(type) {
-	case int:
-		return tab + strconv.FormatInt(int64(value), 10)
-	case int8:
-		return tab + strconv.FormatInt(int64(value), 10)
-	case int16:
-		return tab + strconv.FormatInt(int64(value), 10)
-	case int32:
-		return tab + strconv.FormatInt(int64(value), 10)
-	case int64:
-		return tab + strconv.FormatInt(value, 10)
-	case uint:
-		return tab + strconv.FormatUint(uint64(value), 10)
-	case uint8:
-		return tab + strconv.FormatUint(uint64(value), 10)
-	case uint16:
-		return tab + strconv.FormatUint(uint64(value), 10)
-	case uint32:
-		return tab + strconv.FormatUint(uint64(value), 10)
-	case uint64:
-		return tab + strconv.FormatUint(value, 10)
-	case float32:
-		return tab + strconv.FormatFloat(float64(value), 'f', -1, 32)
-	case float64:
-		return tab + strconv.FormatFloat(value, 'f', -1, 64)
-	case string:
-		return tab + "\"" + encodeTomlString(value) + "\""
-	case bool:
-		if value {
-			return "true"
-		}
-		return "false"
-	case time.Time:
-		return tab + value.Format(time.RFC3339)
-	case []interface{}:
-		result := tab + "[\n"
-		for _, item := range value {
-			result += toTomlValue(item, indent+2) + ",\n"
-		}
-		return result + tab + "]"
-	case nil:
-		return ""
-	default:
-		panic(fmt.Sprintf("unsupported value type %T: %v", value, value))
-	}
-}
-
-// Recursive support function for ToString()
-// Outputs a tree, using the provided keyspace to prefix group names
-func (t *TomlTree) toToml(indent, keyspace string) string {
-	resultChunks := []string{}
-	for k, v := range t.values {
-		// figure out the keyspace
-		combinedKey := k
-		if keyspace != "" {
-			combinedKey = keyspace + "." + combinedKey
-		}
-		resultChunk := ""
-		// output based on type
-		switch node := v.(type) {
-		case []*TomlTree:
-			for _, item := range node {
-				if len(item.Keys()) > 0 {
-					resultChunk += fmt.Sprintf("\n%s[[%s]]\n", indent, combinedKey)
-				}
-				resultChunk += item.toToml(indent+"  ", combinedKey)
-			}
-			resultChunks = append(resultChunks, resultChunk)
-		case *TomlTree:
-			if len(node.Keys()) > 0 {
-				resultChunk += fmt.Sprintf("\n%s[%s]\n", indent, combinedKey)
-			}
-			resultChunk += node.toToml(indent+"  ", combinedKey)
-			resultChunks = append(resultChunks, resultChunk)
-		case map[string]interface{}:
-			sub := TreeFromMap(node)
-
-			if len(sub.Keys()) > 0 {
-				resultChunk += fmt.Sprintf("\n%s[%s]\n", indent, combinedKey)
-			}
-			resultChunk += sub.toToml(indent+"  ", combinedKey)
-			resultChunks = append(resultChunks, resultChunk)
-		case map[string]string:
-			sub := TreeFromMap(convertMapStringString(node))
-
-			if len(sub.Keys()) > 0 {
-				resultChunk += fmt.Sprintf("\n%s[%s]\n", indent, combinedKey)
-			}
-			resultChunk += sub.toToml(indent+"  ", combinedKey)
-			resultChunks = append(resultChunks, resultChunk)
-		case map[interface{}]interface{}:
-			sub := TreeFromMap(convertMapInterfaceInterface(node))
-
-			if len(sub.Keys()) > 0 {
-				resultChunk += fmt.Sprintf("\n%s[%s]\n", indent, combinedKey)
-			}
-			resultChunk += sub.toToml(indent+"  ", combinedKey)
-			resultChunks = append(resultChunks, resultChunk)
-		case *tomlValue:
-			resultChunk = fmt.Sprintf("%s%s = %s\n", indent, k, toTomlValue(node.value, 0))
-			resultChunks = append([]string{resultChunk}, resultChunks...)
-		default:
-			resultChunk = fmt.Sprintf("%s%s = %s\n", indent, k, toTomlValue(v, 0))
-			resultChunks = append([]string{resultChunk}, resultChunks...)
-		}
-
-	}
-	return strings.Join(resultChunks, "")
-}
-
-func convertMapStringString(in map[string]string) map[string]interface{} {
-	result := make(map[string]interface{}, len(in))
-	for k, v := range in {
-		result[k] = v
-	}
-	return result
-}
-
-func convertMapInterfaceInterface(in map[interface{}]interface{}) map[string]interface{} {
-	result := make(map[string]interface{}, len(in))
-	for k, v := range in {
-		result[k.(string)] = v
-	}
-	return result
-}
-
-// ToString is an alias for String
-func (t *TomlTree) ToString() string {
-	return t.String()
-}
-
-// String generates a human-readable representation of the current tree.
-// Output spans multiple lines, and is suitable for ingest by a TOML parser
-func (t *TomlTree) String() string {
-	return t.toToml("", "")
-}
-
-// ToMap recursively generates a representation of the current tree using map[string]interface{}.
-func (t *TomlTree) ToMap() map[string]interface{} {
-	result := map[string]interface{}{}
-
-	for k, v := range t.values {
-		switch node := v.(type) {
-		case []*TomlTree:
-			var array []interface{}
-			for _, item := range node {
-				array = append(array, item.ToMap())
-			}
-			result[k] = array
-		case *TomlTree:
-			result[k] = node.ToMap()
-		case map[string]interface{}:
-			sub := TreeFromMap(node)
-			result[k] = sub.ToMap()
-		case *tomlValue:
-			result[k] = node.value
-		}
-	}
-
-	return result
-}

tomltree_conversions_test.go

@@ -1,171 +0,0 @@
-package toml
-
-import (
-	"reflect"
-	"testing"
-	"time"
-	"strings"
-)
-
-func TestTomlTreeConversionToString(t *testing.T) {
-	toml, err := Load(`name = { first = "Tom", last = "Preston-Werner" }
-points = { x = 1, y = 2 }`)
-
-	if err != nil {
-		t.Fatal("Unexpected error:", err)
-	}
-
-	reparsedTree, err := Load(toml.ToString())
-
-	assertTree(t, reparsedTree, err, map[string]interface{}{
-		"name": map[string]interface{}{
-			"first": "Tom",
-			"last":  "Preston-Werner",
-		},
-		"points": map[string]interface{}{
-			"x": int64(1),
-			"y": int64(2),
-		},
-	})
-}
-
-func TestTomlTreeConversionToStringKeysOrders(t *testing.T) {
-	for i := 0; i < 100; i++ {
-		tree, _ := Load(`
-		foobar = true
-		bar = "baz"
-		foo = 1
-		[qux]
-		  foo = 1
-		  bar = "baz2"`)
-
-		stringRepr := tree.ToString()
-
-		t.Log("Intermediate string representation:")
-		t.Log(stringRepr)
-
-		r := strings.NewReader(stringRepr)
-		toml, err := LoadReader(r)
-
-
-		if err != nil {
-			t.Fatal("Unexpected error:", err)
-		}
-
-		assertTree(t, toml, err, map[string]interface{}{
-			"foobar": true,
-			"bar": "baz",
-			"foo": 1,
-			"qux": map[string]interface{}{
-				"foo": 1,
-				"bar": "baz2",
-			},
-		})
-	}
-}
-
-func testMaps(t *testing.T, actual, expected map[string]interface{}) {
-	if !reflect.DeepEqual(actual, expected) {
-		t.Fatal("trees aren't equal.\n", "Expected:\n", expected, "\nActual:\n", actual)
-	}
-}
-
-func TestTomlTreeConversionToMapSimple(t *testing.T) {
-	tree, _ := Load("a = 42\nb = 17")
-
-	expected := map[string]interface{}{
-		"a": int64(42),
-		"b": int64(17),
-	}
-
-	testMaps(t, tree.ToMap(), expected)
-}
-
-func TestTomlTreeConversionToMapExampleFile(t *testing.T) {
-	tree, _ := LoadFile("example.toml")
-	expected := map[string]interface{}{
-		"title": "TOML Example",
-		"owner": map[string]interface{}{
-			"name":         "Tom Preston-Werner",
-			"organization": "GitHub",
-			"bio":          "GitHub Cofounder & CEO\nLikes tater tots and beer.",
-			"dob":          time.Date(1979, time.May, 27, 7, 32, 0, 0, time.UTC),
-		},
-		"database": map[string]interface{}{
-			"server":         "192.168.1.1",
-			"ports":          []interface{}{int64(8001), int64(8001), int64(8002)},
-			"connection_max": int64(5000),
-			"enabled":        true,
-		},
-		"servers": map[string]interface{}{
-			"alpha": map[string]interface{}{
-				"ip": "10.0.0.1",
-				"dc": "eqdc10",
-			},
-			"beta": map[string]interface{}{
-				"ip": "10.0.0.2",
-				"dc": "eqdc10",
-			},
-		},
-		"clients": map[string]interface{}{
-			"data": []interface{}{
-				[]interface{}{"gamma", "delta"},
-				[]interface{}{int64(1), int64(2)},
-			},
-		},
-	}
-	testMaps(t, tree.ToMap(), expected)
-}
-
-func TestTomlTreeConversionToMapWithTablesInMultipleChunks(t *testing.T) {
-	tree, _ := Load(`
-	[[menu.main]]
-        a = "menu 1"
-        b = "menu 2"
-        [[menu.main]]
-        c = "menu 3"
-        d = "menu 4"`)
-	expected := map[string]interface{}{
-		"menu": map[string]interface{}{
-			"main": []interface{}{
-				map[string]interface{}{"a": "menu 1", "b": "menu 2"},
-				map[string]interface{}{"c": "menu 3", "d": "menu 4"},
-			},
-		},
-	}
-	treeMap := tree.ToMap()
-
-	testMaps(t, treeMap, expected)
-}
-
-func TestTomlTreeConversionToMapWithArrayOfInlineTables(t *testing.T) {
-	tree, _ := Load(`
-    	[params]
-	language_tabs = [
-    		{ key = "shell", name = "Shell" },
-    		{ key = "ruby", name = "Ruby" },
-    		{ key = "python", name = "Python" }
-	]`)
-
-	expected := map[string]interface{}{
-		"params": map[string]interface{}{
-			"language_tabs": []interface{}{
-				map[string]interface{}{
-					"key": "shell",
-					"name": "Shell",
-				},
-				map[string]interface{}{
-					"key": "ruby",
-					"name": "Ruby",
-				},
-				map[string]interface{}{
-					"key": "python",
-					"name": "Python",
-				},
-			},
-		},
-	}
-
-	treeMap := tree.ToMap()
-	testMaps(t, treeMap, expected)
-}

tomltree_write.go

@@ -0,0 +1,212 @@
+package toml
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// encodes a string to a TOML-compliant string value
+func encodeTomlString(value string) string {
+	result := ""
+	for _, rr := range value {
+		switch rr {
+		case '\b':
+			result += "\\b"
+		case '\t':
+			result += "\\t"
+		case '\n':
+			result += "\\n"
+		case '\f':
+			result += "\\f"
+		case '\r':
+			result += "\\r"
+		case '"':
+			result += "\\\""
+		case '\\':
+			result += "\\\\"
+		default:
+			intRr := uint16(rr)
+			if intRr < 0x001F {
+				result += fmt.Sprintf("\\u%0.4X", intRr)
+			} else {
+				result += string(rr)
+			}
+		}
+	}
+	return result
+}
+
+func tomlValueStringRepresentation(v interface{}) (string, error) {
+	switch value := v.(type) {
+	case uint64:
+		return strconv.FormatUint(value, 10), nil
+	case int64:
+		return strconv.FormatInt(value, 10), nil
+	case float64:
+		return strconv.FormatFloat(value, 'f', -1, 32), nil
+	case string:
+		return "\"" + encodeTomlString(value) + "\"", nil
+	case bool:
+		if value {
+			return "true", nil
+		}
+		return "false", nil
+	case time.Time:
+		return value.Format(time.RFC3339), nil
+	case nil:
+		return "", nil
+	case []interface{}:
+		values := []string{}
+		for _, item := range value {
+			itemRepr, err := tomlValueStringRepresentation(item)
+			if err != nil {
+				return "", err
+			}
+			values = append(values, itemRepr)
+		}
+		return "[" + strings.Join(values, ",") + "]", nil
+	default:
+		return "", fmt.Errorf("unsupported value type %T: %v", value, value)
+	}
+}
+
+func (t *TomlTree) writeTo(w io.Writer, indent, keyspace string, bytesCount int64) (int64, error) {
+	simpleValuesKeys := make([]string, 0)
+	complexValuesKeys := make([]string, 0)
+
+	for k := range t.values {
+		v := t.values[k]
+		switch v.(type) {
+		case *TomlTree, []*TomlTree:
+			complexValuesKeys = append(complexValuesKeys, k)
+		default:
+			simpleValuesKeys = append(simpleValuesKeys, k)
+		}
+	}
+
+	sort.Strings(simpleValuesKeys)
+	sort.Strings(complexValuesKeys)
+
+	for _, k := range simpleValuesKeys {
+		v, ok := t.values[k].(*tomlValue)
+		if !ok {
+			return bytesCount, fmt.Errorf("invalid key type at %s: %T", k, t.values[k])
+		}
+
+		repr, err := tomlValueStringRepresentation(v.value)
+		if err != nil {
+			return bytesCount, err
+		}
+
+		kvRepr := fmt.Sprintf("%s%s = %s\n", indent, k, repr)
+		writtenBytesCount, err := w.Write([]byte(kvRepr))
+		bytesCount += int64(writtenBytesCount)
+		if err != nil {
+			return bytesCount, err
+		}
+	}
+
+	for _, k := range complexValuesKeys {
+		v := t.values[k]
+
+		combinedKey := k
+		if keyspace != "" {
+			combinedKey = keyspace + "." + combinedKey
+		}
+
+		switch node := v.(type) {
+		// node has to be of those two types given how keys are sorted above
+		case *TomlTree:
+			tableName := fmt.Sprintf("\n%s[%s]\n", indent, combinedKey)
+			writtenBytesCount, err := w.Write([]byte(tableName))
+			bytesCount += int64(writtenBytesCount)
+			if err != nil {
+				return bytesCount, err
+			}
+			bytesCount, err = node.writeTo(w, indent+"  ", combinedKey, bytesCount)
+			if err != nil {
+				return bytesCount, err
+			}
+		case []*TomlTree:
+			for _, subTree := range node {
+				if len(subTree.values) > 0 {
+					tableArrayName := fmt.Sprintf("\n%s[[%s]]\n", indent, combinedKey)
+					writtenBytesCount, err := w.Write([]byte(tableArrayName))
+					bytesCount += int64(writtenBytesCount)
+					if err != nil {
+						return bytesCount, err
+					}
+
+					bytesCount, err = subTree.writeTo(w, indent+"  ", combinedKey, bytesCount)
+					if err != nil {
+						return bytesCount, err
+					}
+				}
+			}
+		}
+	}
+
+	return bytesCount, nil
+}
+
+// WriteTo encode the TomlTree as Toml and writes it to the writer w.
+// Returns the number of bytes written in case of success, or an error if anything happened.
+func (t *TomlTree) WriteTo(w io.Writer) (int64, error) {
+	return t.writeTo(w, "", "", 0)
+}
+
+// ToTomlString generates a human-readable representation of the current tree.
+// Output spans multiple lines, and is suitable for ingest by a TOML parser.
+// If the conversion cannot be performed, ToString returns a non-nil error.
+func (t *TomlTree) ToTomlString() (string, error) {
+	var buf bytes.Buffer
+	_, err := t.WriteTo(&buf)
+	if err != nil {
+		return "", err
+	}
+	return buf.String(), nil
+}
+
+// String generates a human-readable representation of the current tree.
+// Alias of ToString. Present to implement the fmt.Stringer interface.
+func (t *TomlTree) String() string {
+	result, _ := t.ToTomlString()
+	return result
+}
+
+// ToMap recursively generates a representation of the tree using Go built-in structures.
+// The following types are used:
+// * uint64
+// * int64
+// * bool
+// * string
+// * time.Time
+// * map[string]interface{} (where interface{} is any of this list)
+// * []interface{} (where interface{} is any of this list)
+func (t *TomlTree) ToMap() map[string]interface{} {
+	result := map[string]interface{}{}
+
+	for k, v := range t.values {
+		switch node := v.(type) {
+		case []*TomlTree:
+			var array []interface{}
+			for _, item := range node {
+				array = append(array, item.ToMap())
+			}
+			result[k] = array
+		case *TomlTree:
+			result[k] = node.ToMap()
+		case map[string]interface{}:
+			sub := TreeFromMap(node)
+			result[k] = sub.ToMap()
+		case *tomlValue:
+			result[k] = node.value
+		}
+	}
+	return result
+}

tomltree_write_test.go

@@ -0,0 +1,284 @@
+package toml
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+)
+
+type failingWriter struct {
+	failAt  int
+	written int
+	buffer  bytes.Buffer
+}
+
+func (f failingWriter) Write(p []byte) (n int, err error) {
+	count := len(p)
+	toWrite := f.failAt - count + f.written
+	if toWrite < 0 {
+		toWrite = 0
+	}
+	if toWrite > count {
+		f.written += count
+		f.buffer.WriteString(string(p))
+		return count, nil
+	}
+
+	f.buffer.WriteString(string(p[:toWrite]))
+	f.written = f.failAt
+	return f.written, fmt.Errorf("failingWriter failed after writting %d bytes", f.written)
+}
+
+func assertErrorString(t *testing.T, expected string, err error) {
+	expectedErr := errors.New(expected)
+	if err.Error() != expectedErr.Error() {
+		t.Errorf("expecting error %s, but got %s instead", expected, err)
+	}
+}
+
+func TestTomlTreeWriteToTomlString(t *testing.T) {
+	toml, err := Load(`name = { first = "Tom", last = "Preston-Werner" }
+points = { x = 1, y = 2 }`)
+
+	if err != nil {
+		t.Fatal("Unexpected error:", err)
+	}
+
+	tomlString, _ := toml.ToTomlString()
+	reparsedTree, err := Load(tomlString)
+
+	assertTree(t, reparsedTree, err, map[string]interface{}{
+		"name": map[string]interface{}{
+			"first": "Tom",
+			"last":  "Preston-Werner",
+		},
+		"points": map[string]interface{}{
+			"x": int64(1),
+			"y": int64(2),
+		},
+	})
+}
+
+func TestTomlTreeWriteToTomlStringSimple(t *testing.T) {
+	tree, err := Load("[foo]\n\n[[foo.bar]]\na = 42\n\n[[foo.bar]]\na = 69\n")
+	if err != nil {
+		t.Errorf("Test failed to parse: %v", err)
+		return
+	}
+	result, err := tree.ToTomlString()
+	if err != nil {
+		t.Errorf("Unexpected error: %s", err)
+	}
+	expected := "\n[foo]\n\n  [[foo.bar]]\n    a = 42\n\n  [[foo.bar]]\n    a = 69\n"
+	if result != expected {
+		t.Errorf("Expected got '%s', expected '%s'", result, expected)
+	}
+}
+
+func TestTomlTreeWriteToTomlStringKeysOrders(t *testing.T) {
+	for i := 0; i < 100; i++ {
+		tree, _ := Load(`
+		foobar = true
+		bar = "baz"
+		foo = 1
+		[qux]
+		  foo = 1
+		  bar = "baz2"`)
+
+		stringRepr, _ := tree.ToTomlString()
+
+		t.Log("Intermediate string representation:")
+		t.Log(stringRepr)
+
+		r := strings.NewReader(stringRepr)
+		toml, err := LoadReader(r)
+
+		if err != nil {
+			t.Fatal("Unexpected error:", err)
+		}
+
+		assertTree(t, toml, err, map[string]interface{}{
+			"foobar": true,
+			"bar":    "baz",
+			"foo":    1,
+			"qux": map[string]interface{}{
+				"foo": 1,
+				"bar": "baz2",
+			},
+		})
+	}
+}
+
+func testMaps(t *testing.T, actual, expected map[string]interface{}) {
+	if !reflect.DeepEqual(actual, expected) {
+		t.Fatal("trees aren't equal.\n", "Expected:\n", expected, "\nActual:\n", actual)
+	}
+}
+
+func TestToTomlStringTypeConversionError(t *testing.T) {
+	tree := TomlTree{
+		values: map[string]interface{}{
+			"thing": &tomlValue{[]string{"unsupported"}, Position{}},
+		},
+	}
+	_, err := tree.ToTomlString()
+	expected := errors.New("unsupported value type []string: [unsupported]")
+	if err.Error() != expected.Error() {
+		t.Errorf("expecting error %s, but got %s instead", expected, err)
+	}
+}
+
+func TestTomlTreeWriteToMapSimple(t *testing.T) {
+	tree, _ := Load("a = 42\nb = 17")
+
+	expected := map[string]interface{}{
+		"a": int64(42),
+		"b": int64(17),
+	}
+
+	testMaps(t, tree.ToMap(), expected)
+}
+
+func TestTomlTreeWriteToInvalidTreeSimpleValue(t *testing.T) {
+	tree := TomlTree{values: map[string]interface{}{"foo": int8(1)}}
+	_, err := tree.ToTomlString()
+	assertErrorString(t, "invalid key type at foo: int8", err)
+}
+
+func TestTomlTreeWriteToInvalidTreeTomlValue(t *testing.T) {
+	tree := TomlTree{values: map[string]interface{}{"foo": &tomlValue{int8(1), Position{}}}}
+	_, err := tree.ToTomlString()
+	assertErrorString(t, "unsupported value type int8: 1", err)
+}
+
+func TestTomlTreeWriteToInvalidTreeTomlValueArray(t *testing.T) {
+	tree := TomlTree{values: map[string]interface{}{"foo": &tomlValue{[]interface{}{int8(1)}, Position{}}}}
+	_, err := tree.ToTomlString()
+	assertErrorString(t, "unsupported value type int8: 1", err)
+}
+
+func TestTomlTreeWriteToFailingWriterInSimpleValue(t *testing.T) {
+	toml, _ := Load(`a = 2`)
+	writer := failingWriter{failAt: 0, written: 0}
+	_, err := toml.WriteTo(writer)
+	assertErrorString(t, "failingWriter failed after writting 0 bytes", err)
+}
+
+func TestTomlTreeWriteToFailingWriterInTable(t *testing.T) {
+	toml, _ := Load(`
+[b]
+a = 2`)
+	writer := failingWriter{failAt: 2, written: 0}
+	_, err := toml.WriteTo(writer)
+	assertErrorString(t, "failingWriter failed after writting 2 bytes", err)
+
+	writer = failingWriter{failAt: 13, written: 0}
+	_, err = toml.WriteTo(writer)
+	assertErrorString(t, "failingWriter failed after writting 13 bytes", err)
+}
+
+func TestTomlTreeWriteToFailingWriterInArray(t *testing.T) {
+	toml, _ := Load(`
+[[b]]
+a = 2`)
+	writer := failingWriter{failAt: 2, written: 0}
+	_, err := toml.WriteTo(writer)
+	assertErrorString(t, "failingWriter failed after writting 2 bytes", err)
+
+	writer = failingWriter{failAt: 15, written: 0}
+	_, err = toml.WriteTo(writer)
+	assertErrorString(t, "failingWriter failed after writting 15 bytes", err)
+}
+
+func TestTomlTreeWriteToMapExampleFile(t *testing.T) {
+	tree, _ := LoadFile("example.toml")
+	expected := map[string]interface{}{
+		"title": "TOML Example",
+		"owner": map[string]interface{}{
+			"name":         "Tom Preston-Werner",
+			"organization": "GitHub",
+			"bio":          "GitHub Cofounder & CEO\nLikes tater tots and beer.",
+			"dob":          time.Date(1979, time.May, 27, 7, 32, 0, 0, time.UTC),
+		},
+		"database": map[string]interface{}{
+			"server":         "192.168.1.1",
+			"ports":          []interface{}{int64(8001), int64(8001), int64(8002)},
+			"connection_max": int64(5000),
+			"enabled":        true,
+		},
+		"servers": map[string]interface{}{
+			"alpha": map[string]interface{}{
+				"ip": "10.0.0.1",
+				"dc": "eqdc10",
+			},
+			"beta": map[string]interface{}{
+				"ip": "10.0.0.2",
+				"dc": "eqdc10",
+			},
+		},
+		"clients": map[string]interface{}{
+			"data": []interface{}{
+				[]interface{}{"gamma", "delta"},
+				[]interface{}{int64(1), int64(2)},
+			},
+		},
+	}
+	testMaps(t, tree.ToMap(), expected)
+}
+
+func TestTomlTreeWriteToMapWithTablesInMultipleChunks(t *testing.T) {
+	tree, _ := Load(`
+	[[menu.main]]
+        a = "menu 1"
+        b = "menu 2"
+        [[menu.main]]
+        c = "menu 3"
+        d = "menu 4"`)
+	expected := map[string]interface{}{
+		"menu": map[string]interface{}{
+			"main": []interface{}{
+				map[string]interface{}{"a": "menu 1", "b": "menu 2"},
+				map[string]interface{}{"c": "menu 3", "d": "menu 4"},
+			},
+		},
+	}
+	treeMap := tree.ToMap()
+
+	testMaps(t, treeMap, expected)
+}
+
+func TestTomlTreeWriteToMapWithArrayOfInlineTables(t *testing.T) {
+	tree, _ := Load(`
+    	[params]
+	language_tabs = [
+    		{ key = "shell", name = "Shell" },
+    		{ key = "ruby", name = "Ruby" },
+    		{ key = "python", name = "Python" }
+	]`)
+
+	expected := map[string]interface{}{
+		"params": map[string]interface{}{
+			"language_tabs": []interface{}{
+				map[string]interface{}{
+					"key":  "shell",
+					"name": "Shell",
+				},
+				map[string]interface{}{
+					"key":  "ruby",
+					"name": "Ruby",
+				},
+				map[string]interface{}{
+					"key":  "python",
+					"name": "Python",
+				},
+			},
+		},
+	}
+
+	treeMap := tree.ToMap()
+	testMaps(t, treeMap, expected)
+}