Decoder: check max uint on 32 bit platforms (#778)

Fixes #777

.github/workflows/codeql-analysis.yml

@@ -35,11 +35,11 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v1
+      uses: github/codeql-action/init@v2
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -50,7 +50,7 @@ jobs:
     # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
     # If this step fails, then you should remove it and run the build manually (see below)
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v1
+      uses: github/codeql-action/autobuild@v2
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 https://git.io/JvXDl
@@ -64,4 +64,4 @@ jobs:
     #   make release
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v1
+      uses: github/codeql-action/analyze@v2

.github/workflows/coverage.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: "ubuntu-latest"
     name: report
     steps:
-      - uses: actions/checkout@master
+      - uses: actions/checkout@v3
         with:
           fetch-depth: 0
       - name: Setup go

.github/workflows/release.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           fetch-depth: 0
       - name: Set up Go
@@ -24,7 +24,7 @@ jobs:
         with:
           go-version: 1.18
       - name: Login to GitHub Container Registry
-        uses: docker/login-action@v1
+        uses: docker/login-action@v2
         with:
           registry: ghcr.io
           username: ${{ github.actor }}

.github/workflows/workflow.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     name: ${{ matrix.go }}/${{ matrix.os }}
     steps:
-      - uses: actions/checkout@master
+      - uses: actions/checkout@v3
         with:
           fetch-depth: 0
       - name: Setup go ${{ matrix.go }}

README.md

@@ -38,7 +38,7 @@ operations should not be shockingly slow. See [benchmarks](#benchmarks).
 ### Strict mode
 
 `Decoder` can be set to "strict mode", which makes it error when some parts of
-the TOML document was not prevent in the target structure. This is a great way
+the TOML document was not present in the target structure. This is a great way
 to check for typos. [See example in the documentation][strict].
 
 [strict]: https://pkg.go.dev/github.com/pelletier/go-toml/v2#example-Decoder.DisallowUnknownFields
@@ -540,6 +540,13 @@ complete solutions exist out there.
 [query]: https://github.com/pelletier/go-toml/tree/f99d6bbca119636aeafcf351ee52b3d202782627/query
 [dasel]: https://github.com/TomWright/dasel
 
+## Versioning
+
+Go-toml follows [Semantic Versioning](http://semver.org/). The supported version
+of [TOML](https://github.com/toml-lang/toml) is indicated at the beginning of
+this document. The last two major versions of Go are supported
+(see [Go Release Policy](https://golang.org/doc/devel/release.html#policy)).
+
 ## License
 
 The MIT License (MIT). Read [LICENSE](LICENSE).

marshaler.go

@@ -128,7 +128,8 @@ func (enc *Encoder) SetIndentTables(indent bool) *Encoder {
 //
 // In addition to the "toml" tag struct tag, a "comment" tag can be used to emit
 // a TOML comment before the value being annotated. Comments are ignored inside
-// inline tables.
+// inline tables. For array tables, the comment is only present before the first
+// element of the array.
 func (enc *Encoder) Encode(v interface{}) error {
 	var (
 		b   []byte
@@ -652,10 +653,19 @@ func (enc *Encoder) encodeStruct(b []byte, ctx encoderCtx, v reflect.Value) ([]b
 }
 
 func (enc *Encoder) encodeComment(indent int, comment string, b []byte) []byte {
-	if comment != "" {
+	for len(comment) > 0 {
+		var line string
+		idx := strings.IndexByte(comment, '\n')
+		if idx >= 0 {
+			line = comment[:idx]
+			comment = comment[idx+1:]
+		} else {
+			line = comment
+			comment = ""
+		}
 		b = enc.indent(indent, b)
 		b = append(b, "# "...)
-		b = append(b, comment...)
+		b = append(b, line...)
 		b = append(b, '\n')
 	}
 	return b
@@ -881,6 +891,8 @@ func (enc *Encoder) encodeSliceAsArrayTable(b []byte, ctx encoderCtx, v reflect.
 	scratch = append(scratch, "]]\n"...)
 	ctx.skipTableHeader = true
 
+	b = enc.encodeComment(ctx.indent, ctx.options.comment, b)
+
 	for i := 0; i < v.Len(); i++ {
 		b = append(b, scratch...)
 

marshaler_test.go

@@ -1004,6 +1004,22 @@ func TestIssue752(t *testing.T) {
 	require.Equal(t, "", string(out))
 }
 
+func TestIssue768(t *testing.T) {
+	type cfg struct {
+		Name string `comment:"This is a multiline comment.\nThis is line 2."`
+	}
+
+	out, err := toml.Marshal(&cfg{})
+	require.NoError(t, err)
+
+	expected := `# This is a multiline comment.
+# This is line 2.
+Name = ''
+`
+
+	require.Equal(t, expected, string(out))
+}
+
 func TestMarshalNestedAnonymousStructs(t *testing.T) {
 	type Embedded struct {
 		Value string `toml:"value" json:"value"`

unmarshaler.go

@@ -866,12 +866,27 @@ func (d *decoder) unmarshalFloat(value *ast.Node, v reflect.Value) error {
 	return nil
 }
 
-func (d *decoder) unmarshalInteger(value *ast.Node, v reflect.Value) error {
-	const (
-		maxInt = int64(^uint(0) >> 1)
-		minInt = -maxInt - 1
-	)
+const (
+	maxInt = int64(^uint(0) >> 1)
+	minInt = -maxInt - 1
+)
 
+// Maximum value of uint for decoding. Currently the decoder parses the integer
+// into an int64. As a result, on architectures where uint is 64 bits, the
+// effective maximum uint we can decode is the maximum of int64. On
+// architectures where uint is 32 bits, the maximum value we can decode is
+// lower: the maximum of uint32. I didn't find a way to figure out this value at
+// compile time, so it is computed during initialization.
+var maxUint int64 = math.MaxInt64
+
+func init() {
+	m := uint64(^uint(0))
+	if m < uint64(maxUint) {
+		maxUint = int64(m)
+	}
+}
+
+func (d *decoder) unmarshalInteger(value *ast.Node, v reflect.Value) error {
 	i, err := parseInteger(value.Data)
 	if err != nil {
 		return err
@@ -932,7 +947,7 @@ func (d *decoder) unmarshalInteger(value *ast.Node, v reflect.Value) error {
 
 		r = reflect.ValueOf(uint8(i))
 	case reflect.Uint:
-		if i < 0 {
+		if i < 0 || i > maxUint {
 			return fmt.Errorf("toml: negative number %d does not fit in an uint", i)
 		}
 
@@ -1167,11 +1182,6 @@ func forEachField(t reflect.Type, path []int, do func(name string, path []int))
 		fieldPath := append(path, i)
 		fieldPath = fieldPath[:len(fieldPath):len(fieldPath)]
 
-		if f.Anonymous {
-			forEachField(f.Type, fieldPath, do)
-			continue
-		}
-
 		name := f.Tag.Get("toml")
 		if name == "-" {
 			continue
@@ -1180,6 +1190,12 @@ func forEachField(t reflect.Type, path []int, do func(name string, path []int))
 		if i := strings.IndexByte(name, ','); i >= 0 {
 			name = name[:i]
 		}
+
+		if f.Anonymous && name == "" {
+			forEachField(f.Type, fieldPath, do)
+			continue
+		}
+
 		if name == "" {
 			name = f.Name
 		}

unmarshaler_test.go

@@ -2380,6 +2380,49 @@ func TestIssue714(t *testing.T) {
 	require.Error(t, err)
 }
 
+func TestIssue772(t *testing.T) {
+	type FileHandling struct {
+		FilePattern string `toml:"pattern"`
+	}
+
+	type Config struct {
+		FileHandling `toml:"filehandling"`
+	}
+
+	var defaultConfigFile = []byte(`
+		[filehandling]
+		pattern = "reach-masterdev-"`)
+
+	config := Config{}
+	err := toml.Unmarshal(defaultConfigFile, &config)
+	require.NoError(t, err)
+	require.Equal(t, "reach-masterdev-", config.FileHandling.FilePattern)
+}
+
+func TestIssue774(t *testing.T) {
+	type ScpData struct {
+		Host string `json:"host"`
+	}
+
+	type GenConfig struct {
+		SCP []ScpData `toml:"scp" comment:"Array of Secure Copy Configurations"`
+	}
+
+	c := &GenConfig{}
+	c.SCP = []ScpData{{Host: "main.domain.com"}}
+
+	b, err := toml.Marshal(c)
+	require.NoError(t, err)
+
+	expected := `# Array of Secure Copy Configurations
+[[scp]]
+Host = 'main.domain.com'
+
+`
+
+	require.Equal(t, expected, string(b))
+}
+
 func TestUnmarshalDecodeErrors(t *testing.T) {
 	examples := []struct {
 		desc string