tomll: add multiLineArray flag to linter (#578)

Ask people to go to /discussions for anything that is not a bug report.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,9 +1,18 @@
 ---
 name: Bug report
 about: Create a report to help us improve
-
 ---
 
+<!--
+‼️ Main development focus is on the upcoming go-toml v2 ⚠️
+
+As a result, v1.x bugs will likely not see a fix on a v1.x version.
+However, reporting the bug is the best way to ensure that it will be fixed in v2.
+
+See https://github.com/pelletier/go-toml/discussions/506.
+-->
+
+
 **Describe the bug**
 A clear and concise description of what the bug is.
 
@@ -14,7 +23,7 @@ Steps to reproduce the behavior. Including TOML files.
 A clear and concise description of what you expected to happen, if other than "should work".
 
 **Versions**
- - go-toml: version (git sha)
+ - go-toml: version (or git sha)
  - go: version
  - operating system: e.g. macOS, Windows, Linux
 

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Questions and discussions
+    url: https://github.com/pelletier/go-toml/discussions
+    about: Please ask and answer questions here.

.github/dependabot.yml

@@ -0,0 +1,8 @@
+version: 2
+updates:
+- package-ecosystem: gomod
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "13:00"
+  open-pull-requests-limit: 10

LICENSE

@@ -1,3 +1,13 @@
+The bulk of github.com/pelletier/go-toml is distributed under the MIT license
+(see below), with the exception of localtime.go and localtime.test.go.
+Those two files have been copied over from Google's civil library at revision
+ed46f5086358513cf8c25f8e3f022cb838a49d66, and are distributed under the Apache
+2.0 license (see below).
+
+
+github.com/pelletier/go-toml:
+
+
 The MIT License (MIT)
 
 Copyright (c) 2013 - 2021 Thomas Pelletier, Eric Anderton
@@ -19,3 +29,219 @@ 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.
+
+
+localtime.go, localtime_test.go:
+
+Originals:
+    https://raw.githubusercontent.com/googleapis/google-cloud-go/ed46f5086358513cf8c25f8e3f022cb838a49d66/civil/civil.go
+    https://raw.githubusercontent.com/googleapis/google-cloud-go/ed46f5086358513cf8c25f8e3f022cb838a49d66/civil/civil_test.go
+Changes:
+    * Renamed files from civil* to localtime*.
+    * Package changed from civil to toml.
+    * 'Local' prefix added to all structs.
+License:
+    https://raw.githubusercontent.com/googleapis/google-cloud-go/ed46f5086358513cf8c25f8e3f022cb838a49d66/LICENSE
+
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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README.md

@@ -12,6 +12,31 @@ This library supports TOML version
 [![Go Report Card](https://goreportcard.com/badge/github.com/pelletier/go-toml)](https://goreportcard.com/report/github.com/pelletier/go-toml)
 [![FOSSA Status](https://app.fossa.io/api/projects/git%2Bgithub.com%2Fpelletier%2Fgo-toml.svg?type=shield)](https://app.fossa.io/projects/git%2Bgithub.com%2Fpelletier%2Fgo-toml?ref=badge_shield)
 
+
+## Development status
+
+**ℹ️ Consider go-toml v2!**
+
+The next version of go-toml is in [active development][v2-dev], and
+[nearing completion][v2-map].
+
+Though technically in beta, v2 is already more tested, [fixes bugs][v1-bugs],
+and [much faster][v2-bench]. If you only need reading and writing TOML documents
+(majority of cases), those features are implemented and the API unlikely to
+change.
+
+The remaining features (Document structure editing and tooling) will be added
+shortly. While pull-requests are welcome on v1, no active development is
+expected on it. When v2.0.0 is released, v1 will be deprecated.
+
+👉 [go-toml v2][v2]
+
+[v2]: https://github.com/pelletier/go-toml/tree/v2
+[v2-map]: https://github.com/pelletier/go-toml/discussions/506
+[v2-dev]: https://github.com/pelletier/go-toml/tree/v2
+[v1-bugs]: https://github.com/pelletier/go-toml/issues?q=is%3Aissue+is%3Aopen+label%3Av2-fixed
+[v2-bench]: https://github.com/pelletier/go-toml/tree/v2#benchmarks
+
 ## Features
 
 Go-toml provides the following features for using data parsed from TOML documents:
@@ -109,7 +134,7 @@ Go-toml provides three handy command line tools:
 
 ### Docker image
 
-Those tools are also availble as a Docker image from
+Those tools are also available as a Docker image from
 [dockerhub](https://hub.docker.com/r/pelletier/go-toml). For example, to
 use `tomljson`:
 
@@ -148,4 +173,4 @@ this document. The last two major versions of Go are supported
 
 ## License
 
-The MIT License (MIT). Read [LICENSE](LICENSE).
+The MIT License (MIT) + Apache 2.0. Read [LICENSE](LICENSE).

cmd/tomll/main.go

@@ -6,6 +6,7 @@
 package main
 
 import (
+	"bytes"
 	"flag"
 	"fmt"
 	"io"
@@ -16,6 +17,7 @@ import (
 )
 
 func main() {
+	multiLineArray := flag.Bool("multiLineArray", false, "sets up the linter to encode arrays with more than one element on multiple lines instead of one.")
 	flag.Usage = func() {
 		fmt.Fprintln(os.Stderr, "tomll can be used in two ways:")
 		fmt.Fprintln(os.Stderr, "Writing to STDIN and reading from STDOUT:")
@@ -25,11 +27,16 @@ func main() {
 		fmt.Fprintln(os.Stderr, "  tomll a.toml b.toml c.toml")
 		fmt.Fprintln(os.Stderr, "")
 		fmt.Fprintln(os.Stderr, "When given a list of files, tomll will modify all files in place without asking.")
+		fmt.Fprintln(os.Stderr, "When given a list of files, tomll will modify all files in place without asking.")
+		fmt.Fprintln(os.Stderr, "")
+		fmt.Fprintln(os.Stderr, "Flags:")
+		fmt.Fprintln(os.Stderr, "-multiLineArray      sets up the linter to encode arrays with more than one element on multiple lines instead of one.")
 	}
 	flag.Parse()
+
 	// read from stdin and print to stdout
 	if flag.NArg() == 0 {
-		s, err := lintReader(os.Stdin)
+		s, err := lintReader(os.Stdin, *multiLineArray)
 		if err != nil {
 			io.WriteString(os.Stderr, err.Error())
 			os.Exit(-1)
@@ -38,7 +45,7 @@ func main() {
 	} else {
 		// otherwise modify a list of files
 		for _, filename := range flag.Args() {
-			s, err := lintFile(filename)
+			s, err := lintFile(filename, *multiLineArray)
 			if err != nil {
 				io.WriteString(os.Stderr, err.Error())
 				os.Exit(-1)
@@ -48,18 +55,29 @@ func main() {
 	}
 }
 
-func lintFile(filename string) (string, error) {
+func lintFile(filename string, multiLineArray bool) (string, error) {
 	tree, err := toml.LoadFile(filename)
 	if err != nil {
 		return "", err
 	}
-	return tree.String(), nil
+
+	buf := new(bytes.Buffer)
+	if err := toml.NewEncoder(buf).ArraysWithOneElementPerLine(multiLineArray).Encode(tree); err != nil {
+		panic(err)
+	}
+
+	return buf.String(), nil
 }
 
-func lintReader(r io.Reader) (string, error) {
+func lintReader(r io.Reader, multiLineArray bool) (string, error) {
 	tree, err := toml.LoadReader(r)
 	if err != nil {
 		return "", err
 	}
-	return tree.String(), nil
+
+	buf := new(bytes.Buffer)
+	if err := toml.NewEncoder(buf).ArraysWithOneElementPerLine(multiLineArray).Encode(tree); err != nil {
+		panic(err)
+	}
+	return buf.String(), nil
 }

localtime.go

@@ -1,6 +1,12 @@
 // Implementation of TOML's local date/time.
-// Copied over from https://github.com/googleapis/google-cloud-go/blob/master/civil/civil.go
+//
-// to avoid pulling all the Google dependencies.
+// Copied over from Google's civil to avoid pulling all the Google dependencies.
+// Originals:
+//   https://raw.githubusercontent.com/googleapis/google-cloud-go/ed46f5086358513cf8c25f8e3f022cb838a49d66/civil/civil.go
+// Changes:
+//   * Renamed files from civil* to localtime*.
+//   * Package changed from civil to toml.
+//   * 'Local' prefix added to all structs.
 //
 // Copyright 2016 Google LLC
 //

localtime_test.go

@@ -1,3 +1,13 @@
+// Implementation of TOML's local date/time.
+//
+// Copied over from Google's civil to avoid pulling all the Google dependencies.
+// Originals:
+//   https://raw.githubusercontent.com/googleapis/google-cloud-go/ed46f5086358513cf8c25f8e3f022cb838a49d66/civil/civil_test.go
+// Changes:
+//   * Renamed files from civil* to localtime*.
+//   * Package changed from civil to toml.
+//   * 'Local' prefix added to all structs.
+//
 // Copyright 2016 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");

marshal.go

@@ -258,11 +258,12 @@ type Encoder struct {
 	w io.Writer
 	encOpts
 	annotation
-	line        int
+	line            int
-	col         int
+	col             int
-	order       MarshalOrder
+	order           MarshalOrder
-	promoteAnon bool
+	promoteAnon     bool
-	indentation string
+	compactComments bool
+	indentation     string
 }
 
 // NewEncoder returns a new encoder that writes to w.
@@ -369,6 +370,12 @@ func (e *Encoder) PromoteAnonymous(promote bool) *Encoder {
 	return e
 }
 
+// CompactComments removes the new line before each comment in the tree.
+func (e *Encoder) CompactComments(cc bool) *Encoder {
+	e.compactComments = cc
+	return e
+}
+
 func (e *Encoder) marshal(v interface{}) ([]byte, error) {
 	// Check if indentation is valid
 	for _, char := range e.indentation {
@@ -408,7 +415,7 @@ func (e *Encoder) marshal(v interface{}) ([]byte, error) {
 	}
 
 	var buf bytes.Buffer
-	_, err = t.writeToOrdered(&buf, "", "", 0, e.arraysOneElementPerLine, e.order, e.indentation, false)
+	_, err = t.writeToOrdered(&buf, "", "", 0, e.arraysOneElementPerLine, e.order, e.indentation, e.compactComments, false)
 
 	return buf.Bytes(), err
 }
@@ -591,6 +598,7 @@ func (e *Encoder) wrapTomlValue(val interface{}, parent *Tree) interface{} {
 	_, isTree := val.(*Tree)
 	_, isTreeS := val.([]*Tree)
 	if isTree || isTreeS {
+		e.line++
 		return val
 	}
 

marshal_test.go

@@ -1476,6 +1476,47 @@ commented out"""
 	}
 }
 
+func TestCompactComments(t *testing.T) {
+	expected := []byte(`
+[first-section]
+  # comment for first-key
+  first-key = 1
+  # comment for second-key
+  second-key = "value"
+  # comment for commented third-key
+  # third-key = []
+
+[second-section]
+  # comment for first-key
+  first-key = 2
+  # comment for second-key
+  second-key = "another value"
+  # comment for commented third-key
+  # third-key = ["value1", "value2"]
+`)
+	type Settings struct {
+		FirstKey  int      `toml:"first-key" comment:"comment for first-key"`
+		SecondKey string   `toml:"second-key" comment:"comment for second-key"`
+		ThirdKey  []string `toml:"third-key" comment:"comment for commented third-key" commented:"true"`
+	}
+	type Config struct {
+		FirstSection  Settings `toml:"first-section"`
+		SecondSection Settings `toml:"second-section"`
+	}
+	data := Config{
+		FirstSection:  Settings{1, "value", []string{}},
+		SecondSection: Settings{2, "another value", []string{"value1", "value2"}},
+	}
+	buf := new(bytes.Buffer)
+	if err := NewEncoder(buf).CompactComments(true).Encode(data); err != nil {
+		t.Fatal(err)
+	}
+
+	if !bytes.Equal(expected, buf.Bytes()) {
+		t.Errorf("Bad marshal: expected\n-----\n%s\n-----\ngot\n-----\n%s\n-----\n", expected, buf.Bytes())
+	}
+}
+
 type mapsTestStruct struct {
 	Simple map[string]string
 	Paths  map[string]string

tomltree_write.go

@@ -226,7 +226,9 @@ func tomlValueStringRepresentation(v interface{}, commented string, indent strin
 }
 
 func getTreeArrayLine(trees []*Tree) (line int) {
-	// get lowest line number that is not 0
+	// Prevent returning 0 for empty trees
+	line = int(^uint(0) >> 1)
+	// get lowest line number >= 0
 	for _, tv := range trees {
 		if tv.position.Line < line || line == 0 {
 			line = tv.position.Line
@@ -315,10 +317,10 @@ func sortAlphabetical(t *Tree) (vals []sortNode) {
 }
 
 func (t *Tree) writeTo(w io.Writer, indent, keyspace string, bytesCount int64, arraysOneElementPerLine bool) (int64, error) {
-	return t.writeToOrdered(w, indent, keyspace, bytesCount, arraysOneElementPerLine, OrderAlphabetical, "  ", false)
+	return t.writeToOrdered(w, indent, keyspace, bytesCount, arraysOneElementPerLine, OrderAlphabetical, "  ", false, false)
 }
 
-func (t *Tree) writeToOrdered(w io.Writer, indent, keyspace string, bytesCount int64, arraysOneElementPerLine bool, ord MarshalOrder, indentString string, parentCommented bool) (int64, error) {
+func (t *Tree) writeToOrdered(w io.Writer, indent, keyspace string, bytesCount int64, arraysOneElementPerLine bool, ord MarshalOrder, indentString string, compactComments, parentCommented bool) (int64, error) {
 	var orderedVals []sortNode
 
 	switch ord {
@@ -368,7 +370,7 @@ func (t *Tree) writeToOrdered(w io.Writer, indent, keyspace string, bytesCount i
 				if err != nil {
 					return bytesCount, err
 				}
-				bytesCount, err = node.writeToOrdered(w, indent+indentString, combinedKey, bytesCount, arraysOneElementPerLine, ord, indentString, parentCommented || t.commented || tv.commented)
+				bytesCount, err = node.writeToOrdered(w, indent+indentString, combinedKey, bytesCount, arraysOneElementPerLine, ord, indentString, compactComments, parentCommented || t.commented || tv.commented)
 				if err != nil {
 					return bytesCount, err
 				}
@@ -384,7 +386,7 @@ func (t *Tree) writeToOrdered(w io.Writer, indent, keyspace string, bytesCount i
 						return bytesCount, err
 					}
 
-					bytesCount, err = subTree.writeToOrdered(w, indent+indentString, combinedKey, bytesCount, arraysOneElementPerLine, ord, indentString, parentCommented || t.commented || subTree.commented)
+					bytesCount, err = subTree.writeToOrdered(w, indent+indentString, combinedKey, bytesCount, arraysOneElementPerLine, ord, indentString, compactComments, parentCommented || t.commented || subTree.commented)
 					if err != nil {
 						return bytesCount, err
 					}
@@ -412,7 +414,14 @@ func (t *Tree) writeToOrdered(w io.Writer, indent, keyspace string, bytesCount i
 				if strings.HasPrefix(comment, "#") {
 					start = ""
 				}
-				writtenBytesCountComment, errc := writeStrings(w, "\n", indent, start, comment, "\n")
+				if !compactComments {
+					writtenBytesCountComment, errc := writeStrings(w, "\n")
+					bytesCount += int64(writtenBytesCountComment)
+					if errc != nil {
+						return bytesCount, errc
+					}
+				}
+				writtenBytesCountComment, errc := writeStrings(w, indent, start, comment, "\n")
 				bytesCount += int64(writtenBytesCountComment)
 				if errc != nil {
 					return bytesCount, errc

tomltree_write_test.go

@@ -364,6 +364,55 @@ c = nan`
 	}
 }
 
+func TestOrderedEmptyTrees(t *testing.T) {
+	type val struct {
+		Key string `toml:"key"`
+	}
+	type structure struct {
+		First val   `toml:"first"`
+		Empty []val `toml:"empty"`
+	}
+	input := structure{First: val{Key: "value"}}
+	buf := new(bytes.Buffer)
+	err := NewEncoder(buf).Order(OrderPreserve).Encode(input)
+	if err != nil {
+		t.Fatal("failed to encode input")
+	}
+	expected := `
+[first]
+  key = "value"
+`
+	if expected != buf.String() {
+		t.Fatal("expected and encoded body aren't equal: ", expected, buf.String())
+	}
+}
+
+func TestOrderedNonIncreasedLine(t *testing.T) {
+	type NiceMap map[string]string
+	type Manifest struct {
+		NiceMap `toml:"dependencies"`
+		Build   struct {
+			BuildCommand string `toml:"build-command"`
+		} `toml:"build"`
+	}
+
+	test := &Manifest{}
+	test.Build.BuildCommand = "test"
+	buf := new(bytes.Buffer)
+	if err := NewEncoder(buf).Order(OrderPreserve).Encode(test); err != nil {
+		panic(err)
+	}
+	expected := `
+[dependencies]
+
+[build]
+  build-command = "test"
+`
+	if expected != buf.String() {
+		t.Fatal("expected and encoded body aren't equal: ", expected, buf.String())
+	}
+}
+
 func TestIssue290(t *testing.T) {
 	tomlString :=
 		`[table]