Merge pull request #267 from dennwc/linter

Fix code style issues

common/license/key.go

@@ -40,92 +40,92 @@ type LicenseKey struct {
 	CreatorEmail string     `json:"creator_email"`
 }
 
-func (this *LicenseKey) isExpired() bool {
+func (k *LicenseKey) isExpired() bool {
-	if this.ExpiresAt == nil {
+	if k.ExpiresAt == nil {
 		return false
 	}
 
-	if this.CreatedAt.Before(startCheckingExpiry) {
+	if k.CreatedAt.Before(startCheckingExpiry) {
 		return false
 	}
 
 	utcNow := time.Now().UTC()
-	return utcNow.After(*this.ExpiresAt)
+	return utcNow.After(*k.ExpiresAt)
 }
 
-func (this *LicenseKey) Validate() error {
+func (k *LicenseKey) Validate() error {
-	if len(this.LicenseId) < 10 {
+	if len(k.LicenseId) < 10 {
 		return fmt.Errorf("Invalid license: License Id")
 	}
 
-	if len(this.CustomerId) < 10 {
+	if len(k.CustomerId) < 10 {
 		return fmt.Errorf("Invalid license: Customer Id")
 	}
 
-	if len(this.CustomerName) < 1 {
+	if len(k.CustomerName) < 1 {
 		return fmt.Errorf("Invalid license: Customer Name")
 	}
 
-	if testTime.After(this.CreatedAt) {
+	if testTime.After(k.CreatedAt) {
 		return fmt.Errorf("Invalid license: Created At is invalid")
 	}
 
-	if this.ExpiresAt != nil {
+	if k.ExpiresAt != nil {
-		if this.CreatedAt.After(*this.ExpiresAt) {
+		if k.CreatedAt.After(*k.ExpiresAt) {
 			return fmt.Errorf("Invalid license: Created At cannot be Greater than Expires At")
 		}
 	}
 
-	if this.isExpired() {
+	if k.isExpired() {
 		return fmt.Errorf("Invalid license: The license has already expired")
 	}
 
-	if len(this.CreatorName) < 1 {
+	if len(k.CreatorName) < 1 {
 		return fmt.Errorf("Invalid license: Creator name")
 	}
 
-	if len(this.CreatorEmail) < 1 {
+	if len(k.CreatorEmail) < 1 {
 		return fmt.Errorf("Invalid license: Creator email")
 	}
 
 	return nil
 }
 
-func (this *LicenseKey) TypeToString() string {
+func (k *LicenseKey) TypeToString() string {
-	if this.Tier == LicenseTierUnlicensed {
+	if k.Tier == LicenseTierUnlicensed {
 		return "Unlicensed"
 	}
 
-	if this.Tier == LicenseTierCommunity {
+	if k.Tier == LicenseTierCommunity {
 		return "AGPLv3 Open Source Community License"
 	}
 
-	if this.Tier == LicenseTierIndividual || this.Tier == "indie" {
+	if k.Tier == LicenseTierIndividual || k.Tier == "indie" {
 		return "Commercial License - Individual"
 	}
 
 	return "Commercial License - Business"
 }
 
-func (this *LicenseKey) ToString() string {
+func (k *LicenseKey) ToString() string {
-	str := fmt.Sprintf("License Id: %s\n", this.LicenseId)
+	str := fmt.Sprintf("License Id: %s\n", k.LicenseId)
-	str += fmt.Sprintf("Customer Id: %s\n", this.CustomerId)
+	str += fmt.Sprintf("Customer Id: %s\n", k.CustomerId)
-	str += fmt.Sprintf("Customer Name: %s\n", this.CustomerName)
+	str += fmt.Sprintf("Customer Name: %s\n", k.CustomerName)
-	str += fmt.Sprintf("Tier: %s\n", this.Tier)
+	str += fmt.Sprintf("Tier: %s\n", k.Tier)
-	str += fmt.Sprintf("Created At: %s\n", common.UtcTimeFormat(this.CreatedAt))
+	str += fmt.Sprintf("Created At: %s\n", common.UtcTimeFormat(k.CreatedAt))
 
-	if this.ExpiresAt == nil {
+	if k.ExpiresAt == nil {
 		str += fmt.Sprintf("Expires At: Never\n")
 	} else {
-		str += fmt.Sprintf("Expires At: %s\n", common.UtcTimeFormat(*this.ExpiresAt))
+		str += fmt.Sprintf("Expires At: %s\n", common.UtcTimeFormat(*k.ExpiresAt))
 	}
 
-	str += fmt.Sprintf("Creator: %s <%s>\n", this.CreatorName, this.CreatorEmail)
+	str += fmt.Sprintf("Creator: %s <%s>\n", k.CreatorName, k.CreatorEmail)
 	return str
 }
 
-func (lk *LicenseKey) IsLicensed() bool {
+func (k *LicenseKey) IsLicensed() bool {
-	return lk.Tier != LicenseTierUnlicensed
+	return k.Tier != LicenseTierUnlicensed
 }
 
 func MakeUnlicensedKey() *LicenseKey {

common/license/util.go

@@ -12,9 +12,9 @@ import (
 )
 
 // Defaults to the open source license.
-var licenseKey *LicenseKey = MakeUnlicensedKey()
+var licenseKey = MakeUnlicensedKey()
 
-// Sets and validates the license key.
+// SetLicenseKey sets and validates the license key.
 func SetLicenseKey(content string, customerName string) error {
 	lk, err := licenseKeyDecode(content)
 	if err != nil {

common/logging.go

@@ -21,28 +21,28 @@ type Logger interface {
 	Trace(format string, args ...interface{})
 }
 
-// Dummy Logger does nothing.
+// DummyLogger does nothing.
 type DummyLogger struct{}
 
-func (this DummyLogger) Error(format string, args ...interface{}) {
+func (DummyLogger) Error(format string, args ...interface{}) {
 }
 
-func (this DummyLogger) Warning(format string, args ...interface{}) {
+func (DummyLogger) Warning(format string, args ...interface{}) {
 }
 
-func (this DummyLogger) Notice(format string, args ...interface{}) {
+func (DummyLogger) Notice(format string, args ...interface{}) {
 }
 
-func (this DummyLogger) Info(format string, args ...interface{}) {
+func (DummyLogger) Info(format string, args ...interface{}) {
 }
 
-func (this DummyLogger) Debug(format string, args ...interface{}) {
+func (DummyLogger) Debug(format string, args ...interface{}) {
 }
 
-func (this DummyLogger) Trace(format string, args ...interface{}) {
+func (DummyLogger) Trace(format string, args ...interface{}) {
 }
 
-// Simple Console Logger that the tests use.
+// LogLevel is the verbosity level for logging.
 type LogLevel int
 
 const (
@@ -64,45 +64,45 @@ func NewConsoleLogger(logLevel LogLevel) *ConsoleLogger {
 	return &logger
 }
 
-func (this ConsoleLogger) Error(format string, args ...interface{}) {
+func (l ConsoleLogger) Error(format string, args ...interface{}) {
-	if this.LogLevel >= LogLevelError {
+	if l.LogLevel >= LogLevelError {
 		prefix := "[ERROR] "
-		this.output(os.Stdout, prefix, format, args...)
+		l.output(os.Stdout, prefix, format, args...)
 	}
 }
 
-func (this ConsoleLogger) Warning(format string, args ...interface{}) {
+func (l ConsoleLogger) Warning(format string, args ...interface{}) {
-	if this.LogLevel >= LogLevelWarning {
+	if l.LogLevel >= LogLevelWarning {
 		prefix := "[WARNING] "
-		this.output(os.Stdout, prefix, format, args...)
+		l.output(os.Stdout, prefix, format, args...)
 	}
 }
 
-func (this ConsoleLogger) Notice(format string, args ...interface{}) {
+func (l ConsoleLogger) Notice(format string, args ...interface{}) {
-	if this.LogLevel >= LogLevelNotice {
+	if l.LogLevel >= LogLevelNotice {
 		prefix := "[NOTICE] "
-		this.output(os.Stdout, prefix, format, args...)
+		l.output(os.Stdout, prefix, format, args...)
 	}
 }
 
-func (this ConsoleLogger) Info(format string, args ...interface{}) {
+func (l ConsoleLogger) Info(format string, args ...interface{}) {
-	if this.LogLevel >= LogLevelInfo {
+	if l.LogLevel >= LogLevelInfo {
 		prefix := "[INFO] "
-		this.output(os.Stdout, prefix, format, args...)
+		l.output(os.Stdout, prefix, format, args...)
 	}
 }
 
-func (this ConsoleLogger) Debug(format string, args ...interface{}) {
+func (l ConsoleLogger) Debug(format string, args ...interface{}) {
-	if this.LogLevel >= LogLevelDebug {
+	if l.LogLevel >= LogLevelDebug {
 		prefix := "[DEBUG] "
-		this.output(os.Stdout, prefix, format, args...)
+		l.output(os.Stdout, prefix, format, args...)
 	}
 }
 
-func (this ConsoleLogger) Trace(format string, args ...interface{}) {
+func (l ConsoleLogger) Trace(format string, args ...interface{}) {
-	if this.LogLevel >= LogLevelTrace {
+	if l.LogLevel >= LogLevelTrace {
 		prefix := "[TRACE] "
-		this.output(os.Stdout, prefix, format, args...)
+		l.output(os.Stdout, prefix, format, args...)
 	}
 }
 
@@ -113,7 +113,7 @@ func SetLogger(logger Logger) {
 }
 
 // output writes `format`, `args` log message prefixed by the source file name, line and `prefix`
-func (this ConsoleLogger) output(f *os.File, prefix string, format string, args ...interface{}) {
+func (l ConsoleLogger) output(f *os.File, prefix string, format string, args ...interface{}) {
 	_, file, line, ok := runtime.Caller(2)
 	if !ok {
 		file = "???"

common/version.go

@@ -16,7 +16,7 @@ const releaseDay = 14
 const releaseHour = 19
 const releaseMin = 40
 
-// Holds version information, when bumping this make sure to bump the released at stamp also.
+// Version holds version information, when bumping this make sure to bump the released at stamp also.
 const Version = "2.1.1"
 
 var ReleasedAt = time.Date(releaseYear, releaseMonth, releaseDay, releaseHour, releaseMin, 0, 0, time.UTC)

doc.go

@@ -3,7 +3,7 @@
  * file 'LICENSE.md', which is part of this source code package.
  */
 
-// UniDoc is a comprehensive PDF library for Go (golang). The library has advanced capabilities for generating,
+// Package unidoc is a comprehensive PDF library for Go (golang). The library has advanced capabilities for generating,
 // processing and modifying PDFs. UniDoc is written and supported by the owners of the
 // FoxyUtils.com website, where the library is used to power many of the PDF services offered.
 //

pdf/annotator/circle.go

@@ -26,7 +26,8 @@ type CircleAnnotationDef struct {
 	Opacity       float64 // Alpha value (0-1).
 }
 
-// Creates a circle/ellipse annotation object with appearance stream that can be added to page PDF annotations.
+// CreateCircleAnnotation creates a circle/ellipse annotation object with appearance stream that can be added to
+// page PDF annotations.
 func CreateCircleAnnotation(circDef CircleAnnotationDef) (*pdf.PdfAnnotation, error) {
 	circAnnotation := pdf.NewPdfAnnotationCircle()
 

pdf/annotator/field_appearance.go

@@ -731,6 +731,8 @@ func genFieldTextCombAppearance(wa *model.PdfAnnotationWidget, ftxt *model.PdfFi
 // genFieldCheckboxAppearance generates an appearance dictionary for a widget annotation `wa` referenced by
 // a button field `fbtn` with form resources `dr` (DR).
 func genFieldCheckboxAppearance(wa *model.PdfAnnotationWidget, fbtn *model.PdfFieldButton, dr *model.PdfPageResources, style AppearanceStyle) (*core.PdfObjectDictionary, error) {
+	// TODO(dennwc): unused parameters
+
 	// Get bounding Rect.
 	array, ok := core.GetArray(wa.Rect)
 	if !ok {

pdf/annotator/line.go

@@ -12,8 +12,8 @@ import (
 	pdf "github.com/unidoc/unidoc/pdf/model"
 )
 
-// Defines a line between point 1 (X1,Y1) and point 2 (X2,Y2).  The line ending styles can be none (regular line),
+// LineAnnotationDef defines a line between point 1 (X1,Y1) and point 2 (X2,Y2).  The line ending styles can be none
-// or arrows at either end.  The line also has a specified width, color and opacity.
+// (regular line), or arrows at either end.  The line also has a specified width, color and opacity.
 type LineAnnotationDef struct {
 	X1               float64
 	Y1               float64
@@ -26,7 +26,7 @@ type LineAnnotationDef struct {
 	LineEndingStyle2 draw.LineEndingStyle // Line ending style of point 2.
 }
 
-// Creates a line annotation object that can be added to page PDF annotations.
+// CreateLineAnnotation creates a line annotation object that can be added to page PDF annotations.
 func CreateLineAnnotation(lineDef LineAnnotationDef) (*pdf.PdfAnnotation, error) {
 	// Line annotation.
 	lineAnnotation := pdf.NewPdfAnnotationLine()

pdf/annotator/rectangle.go

@@ -13,8 +13,8 @@ import (
 	pdf "github.com/unidoc/unidoc/pdf/model"
 )
 
-// A rectangle defined with a specified Width and Height and a lower left corner at (X,Y).  The rectangle can
+// RectangleAnnotationDef is a rectangle defined with a specified Width and Height and a lower left corner at (X,Y).
-// optionally have a border and a filling color.
+// The rectangle can optionally have a border and a filling color.
 // The Width/Height includes the border (if any specified).
 type RectangleAnnotationDef struct {
 	X             float64
@@ -29,7 +29,7 @@ type RectangleAnnotationDef struct {
 	Opacity       float64 // Alpha value (0-1).
 }
 
-// Creates a rectangle annotation object that can be added to page PDF annotations.
+// CreateRectangleAnnotation creates a rectangle annotation object that can be added to page PDF annotations.
 func CreateRectangleAnnotation(rectDef RectangleAnnotationDef) (*pdf.PdfAnnotation, error) {
 	rectAnnotation := pdf.NewPdfAnnotationSquare()
 

pdf/contentstream/contentstream.go

@@ -89,12 +89,12 @@ func (ops *ContentStreamOperations) Bytes() []byte {
 		if op.Operand == "BI" {
 			// Inline image requires special handling.
 			buf.WriteString(op.Operand + "\n")
-			buf.WriteString(op.Params[0].DefaultWriteString())
+			buf.WriteString(op.Params[0].WriteString())
 
 		} else {
 			// Default handler.
 			for _, param := range op.Params {
-				buf.WriteString(param.DefaultWriteString())
+				buf.WriteString(param.WriteString())
 				buf.WriteString(" ")
 
 			}

pdf/contentstream/draw/bezier_curve.go

@@ -11,7 +11,7 @@ import (
 	"github.com/unidoc/unidoc/pdf/model"
 )
 
-// Cubic bezier curves are defined by:
+// CubicBezierCurve is defined by:
 // R(t) = P0*(1-t)^3 + P1*3*t*(1-t)^2 + P2*3*t^2*(1-t) + P3*t^3
 // where P0 is the current point, P1, P2 control points and P3 the final point.
 type CubicBezierCurve struct {
@@ -30,7 +30,7 @@ func NewCubicBezierCurve(x0, y0, x1, y1, x2, y2, x3, y3 float64) CubicBezierCurv
 	return curve
 }
 
-// Add X,Y offset to all points on a curve.
+// AddOffsetXY adds X,Y offset to all points on a curve.
 func (curve CubicBezierCurve) AddOffsetXY(offX, offY float64) CubicBezierCurve {
 	curve.P0.X += offX
 	curve.P1.X += offX
@@ -94,35 +94,35 @@ func NewCubicBezierPath() CubicBezierPath {
 	return bpath
 }
 
-func (this CubicBezierPath) AppendCurve(curve CubicBezierCurve) CubicBezierPath {
+func (p CubicBezierPath) AppendCurve(curve CubicBezierCurve) CubicBezierPath {
-	this.Curves = append(this.Curves, curve)
+	p.Curves = append(p.Curves, curve)
-	return this
+	return p
 }
 
-func (bpath CubicBezierPath) Copy() CubicBezierPath {
+func (p CubicBezierPath) Copy() CubicBezierPath {
 	bpathcopy := CubicBezierPath{}
 	bpathcopy.Curves = []CubicBezierCurve{}
-	for _, c := range bpath.Curves {
+	for _, c := range p.Curves {
 		bpathcopy.Curves = append(bpathcopy.Curves, c)
 	}
 	return bpathcopy
 }
 
-func (bpath CubicBezierPath) Offset(offX, offY float64) CubicBezierPath {
+func (p CubicBezierPath) Offset(offX, offY float64) CubicBezierPath {
-	for i, c := range bpath.Curves {
+	for i, c := range p.Curves {
-		bpath.Curves[i] = c.AddOffsetXY(offX, offY)
+		p.Curves[i] = c.AddOffsetXY(offX, offY)
 	}
-	return bpath
+	return p
 }
 
-func (bpath CubicBezierPath) GetBoundingBox() Rectangle {
+func (p CubicBezierPath) GetBoundingBox() Rectangle {
 	bbox := Rectangle{}
 
 	minX := 0.0
 	maxX := 0.0
 	minY := 0.0
 	maxY := 0.0
-	for idx, c := range bpath.Curves {
+	for idx, c := range p.Curves {
 		curveBounds := c.GetBounds()
 		if idx == 0 {
 			minX = curveBounds.Llx

pdf/contentstream/draw/path.go

@@ -5,67 +5,65 @@
 
 package draw
 
-// A path consists of straight line connections between each point defined in an array of points.
+// Path consists of straight line connections between each point defined in an array of points.
 type Path struct {
 	Points []Point
 }
 
 func NewPath() Path {
-	path := Path{}
+	return Path{}
-	path.Points = []Point{}
-	return path
 }
 
-func (this Path) AppendPoint(point Point) Path {
+func (p Path) AppendPoint(point Point) Path {
-	this.Points = append(this.Points, point)
+	p.Points = append(p.Points, point)
-	return this
+	return p
 }
 
-func (this Path) RemovePoint(number int) Path {
+func (p Path) RemovePoint(number int) Path {
-	if number < 1 || number > len(this.Points) {
+	if number < 1 || number > len(p.Points) {
-		return this
+		return p
 	}
 
 	idx := number - 1
-	this.Points = append(this.Points[:idx], this.Points[idx+1:]...)
+	p.Points = append(p.Points[:idx], p.Points[idx+1:]...)
-	return this
+	return p
 }
 
-func (this Path) Length() int {
+func (p Path) Length() int {
-	return len(this.Points)
+	return len(p.Points)
 }
 
-func (this Path) GetPointNumber(number int) Point {
+func (p Path) GetPointNumber(number int) Point {
-	if number < 1 || number > len(this.Points) {
+	if number < 1 || number > len(p.Points) {
 		return Point{}
 	}
-	return this.Points[number-1]
+	return p.Points[number-1]
 }
 
-func (path Path) Copy() Path {
+func (p Path) Copy() Path {
 	pathcopy := Path{}
 	pathcopy.Points = []Point{}
-	for _, p := range path.Points {
+	for _, p := range p.Points {
 		pathcopy.Points = append(pathcopy.Points, p)
 	}
 	return pathcopy
 }
 
-func (path Path) Offset(offX, offY float64) Path {
+func (p Path) Offset(offX, offY float64) Path {
-	for i, p := range path.Points {
+	for i, pt := range p.Points {
-		path.Points[i] = p.Add(offX, offY)
+		p.Points[i] = pt.Add(offX, offY)
 	}
-	return path
+	return p
 }
 
-func (path Path) GetBoundingBox() BoundingBox {
+func (p Path) GetBoundingBox() BoundingBox {
 	bbox := BoundingBox{}
 
 	minX := 0.0
 	maxX := 0.0
 	minY := 0.0
 	maxY := 0.0
-	for idx, p := range path.Points {
+	for idx, p := range p.Points {
 		if idx == 0 {
 			minX = p.X
 			maxX = p.X

pdf/contentstream/draw/point.go

@@ -13,10 +13,7 @@ type Point struct {
 }
 
 func NewPoint(x, y float64) Point {
-	point := Point{}
+	return Point{X: x, Y: y}
-	point.X = x
-	point.Y = y
-	return point
 }
 
 func (p Point) Add(dx, dy float64) Point {
@@ -25,11 +22,11 @@ func (p Point) Add(dx, dy float64) Point {
 	return p
 }
 
-// Add vector to a point.
+// AddVector adds vector to a point.
-func (this Point) AddVector(v Vector) Point {
+func (p Point) AddVector(v Vector) Point {
-	this.X += v.Dx
+	p.X += v.Dx
-	this.Y += v.Dy
+	p.Y += v.Dy
-	return this
+	return p
 }
 
 func (p Point) String() string {

pdf/contentstream/draw/utils.go

@@ -4,7 +4,7 @@ import (
 	pdfcontent "github.com/unidoc/unidoc/pdf/contentstream"
 )
 
-// Make the path with the content creator.
+// DrawPathWithCreator makes the path with the content creator.
 // Adds the PDF commands to draw the path to the creator instance.
 func DrawPathWithCreator(path Path, creator *pdfcontent.ContentCreator) {
 	for idx, p := range path.Points {
@@ -16,7 +16,7 @@ func DrawPathWithCreator(path Path, creator *pdfcontent.ContentCreator) {
 	}
 }
 
-// Make the bezier path with the content creator.
+// DrawBezierPathWithCreator makes the bezier path with the content creator.
 // Adds the PDF commands to draw the path to the creator instance.
 func DrawBezierPathWithCreator(bpath CubicBezierPath, creator *pdfcontent.ContentCreator) {
 	for idx, c := range bpath.Curves {

pdf/contentstream/draw/vector.go

@@ -47,14 +47,14 @@ func (v Vector) Rotate(phi float64) Vector {
 	return NewVectorPolar(mag, angle+phi)
 }
 
-// Change the sign of the vector: -vector.
+// Flip changes the sign of the vector: -vector.
-func (this Vector) Flip() Vector {
+func (v Vector) Flip() Vector {
-	mag := this.Magnitude()
+	mag := v.Magnitude()
-	theta := this.GetPolarAngle()
+	theta := v.GetPolarAngle()
 
-	this.Dx = mag * math.Cos(theta+math.Pi)
+	v.Dx = mag * math.Cos(theta+math.Pi)
-	this.Dy = mag * math.Sin(theta+math.Pi)
+	v.Dy = mag * math.Sin(theta+math.Pi)
-	return this
+	return v
 }
 
 func (v Vector) FlipY() Vector {
@@ -67,19 +67,19 @@ func (v Vector) FlipX() Vector {
 	return v
 }
 
-func (this Vector) Scale(factor float64) Vector {
+func (v Vector) Scale(factor float64) Vector {
-	mag := this.Magnitude()
+	mag := v.Magnitude()
-	theta := this.GetPolarAngle()
+	theta := v.GetPolarAngle()
 
-	this.Dx = factor * mag * math.Cos(theta)
+	v.Dx = factor * mag * math.Cos(theta)
-	this.Dy = factor * mag * math.Sin(theta)
+	v.Dy = factor * mag * math.Sin(theta)
-	return this
+	return v
 }
 
-func (this Vector) Magnitude() float64 {
+func (v Vector) Magnitude() float64 {
-	return math.Sqrt(math.Pow(this.Dx, 2.0) + math.Pow(this.Dy, 2.0))
+	return math.Sqrt(math.Pow(v.Dx, 2.0) + math.Pow(v.Dy, 2.0))
 }
 
-func (this Vector) GetPolarAngle() float64 {
+func (v Vector) GetPolarAngle() float64 {
-	return math.Atan2(this.Dy, this.Dx)
+	return math.Atan2(v.Dy, v.Dx)
 }

pdf/contentstream/encoding.go

@@ -301,7 +301,7 @@ func newMultiEncoderFromInlineImage(inlineImage *ContentStreamInlineImage) (*cor
 	// Prepare the decode params array (one for each filter type)
 	// Optional, not always present.
 	var decodeParamsDict *core.PdfObjectDictionary
-	decodeParamsArray := []core.PdfObject{}
+	var decodeParamsArray []core.PdfObject
 	if obj := inlineImage.DecodeParms; obj != nil {
 		// If it is a dictionary, assume it applies to all
 		dict, isDict := obj.(*core.PdfObjectDictionary)
@@ -360,7 +360,7 @@ func newMultiEncoderFromInlineImage(inlineImage *ContentStreamInlineImage) (*cor
 		}
 
 		if *name == core.StreamEncodingFilterNameFlate || *name == "Fl" {
-			// XXX: need to separate out the DecodeParms..
+			// TODO: need to separate out the DecodeParms..
 			encoder, err := newFlateEncoderFromInlineImage(inlineImage, dParams)
 			if err != nil {
 				return nil, err

pdf/contentstream/inline-image.go

@@ -15,7 +15,7 @@ import (
 	"github.com/unidoc/unidoc/pdf/model"
 )
 
-// A representation of an inline image in a Content stream. Everything between the BI and EI operands.
+// ContentStreamInlineImage is a representation of an inline image in a Content stream. Everything between the BI and EI operands.
 // ContentStreamInlineImage implements the core.PdfObject interface although strictly it is not a PDF object.
 type ContentStreamInlineImage struct {
 	BitsPerComponent core.PdfObject
@@ -31,7 +31,7 @@ type ContentStreamInlineImage struct {
 	stream           []byte
 }
 
-// Make a new content stream inline image object from an image.
+// NewInlineImageFromImage makes a new content stream inline image object from an image.
 func NewInlineImageFromImage(img model.Image, encoder core.StreamEncoder) (*ContentStreamInlineImage, error) {
 	if encoder == nil {
 		encoder = core.NewRawEncoder()
@@ -63,7 +63,7 @@ func NewInlineImageFromImage(img model.Image, encoder core.StreamEncoder) (*Cont
 	if filterName != core.StreamEncodingFilterNameRaw {
 		inlineImage.Filter = core.MakeName(filterName)
 	}
-	// XXX/FIXME: Add decode params?
+	// FIXME: Add decode params?
 
 	return &inlineImage, nil
 }
@@ -71,39 +71,39 @@ func NewInlineImageFromImage(img model.Image, encoder core.StreamEncoder) (*Cont
 func (img *ContentStreamInlineImage) String() string {
 	s := fmt.Sprintf("InlineImage(len=%d)\n", len(img.stream))
 	if img.BitsPerComponent != nil {
-		s += "- BPC " + img.BitsPerComponent.DefaultWriteString() + "\n"
+		s += "- BPC " + img.BitsPerComponent.WriteString() + "\n"
 	}
 	if img.ColorSpace != nil {
-		s += "- CS " + img.ColorSpace.DefaultWriteString() + "\n"
+		s += "- CS " + img.ColorSpace.WriteString() + "\n"
 	}
 	if img.Decode != nil {
-		s += "- D " + img.Decode.DefaultWriteString() + "\n"
+		s += "- D " + img.Decode.WriteString() + "\n"
 	}
 	if img.DecodeParms != nil {
-		s += "- DP " + img.DecodeParms.DefaultWriteString() + "\n"
+		s += "- DP " + img.DecodeParms.WriteString() + "\n"
 	}
 	if img.Filter != nil {
-		s += "- F " + img.Filter.DefaultWriteString() + "\n"
+		s += "- F " + img.Filter.WriteString() + "\n"
 	}
 	if img.Height != nil {
-		s += "- H " + img.Height.DefaultWriteString() + "\n"
+		s += "- H " + img.Height.WriteString() + "\n"
 	}
 	if img.ImageMask != nil {
-		s += "- IM " + img.ImageMask.DefaultWriteString() + "\n"
+		s += "- IM " + img.ImageMask.WriteString() + "\n"
 	}
 	if img.Intent != nil {
-		s += "- Intent " + img.Intent.DefaultWriteString() + "\n"
+		s += "- Intent " + img.Intent.WriteString() + "\n"
 	}
 	if img.Interpolate != nil {
-		s += "- I " + img.Interpolate.DefaultWriteString() + "\n"
+		s += "- I " + img.Interpolate.WriteString() + "\n"
 	}
 	if img.Width != nil {
-		s += "- W " + img.Width.DefaultWriteString() + "\n"
+		s += "- W " + img.Width.WriteString() + "\n"
 	}
 	return s
 }
 
-func (img *ContentStreamInlineImage) DefaultWriteString() string {
+func (img *ContentStreamInlineImage) WriteString() string {
 	var output bytes.Buffer
 
 	// We do not start with "BI" as that is the operand and is written out separately.
@@ -111,34 +111,34 @@ func (img *ContentStreamInlineImage) DefaultWriteString() string {
 	s := ""
 
 	if img.BitsPerComponent != nil {
-		s += "/BPC " + img.BitsPerComponent.DefaultWriteString() + "\n"
+		s += "/BPC " + img.BitsPerComponent.WriteString() + "\n"
 	}
 	if img.ColorSpace != nil {
-		s += "/CS " + img.ColorSpace.DefaultWriteString() + "\n"
+		s += "/CS " + img.ColorSpace.WriteString() + "\n"
 	}
 	if img.Decode != nil {
-		s += "/D " + img.Decode.DefaultWriteString() + "\n"
+		s += "/D " + img.Decode.WriteString() + "\n"
 	}
 	if img.DecodeParms != nil {
-		s += "/DP " + img.DecodeParms.DefaultWriteString() + "\n"
+		s += "/DP " + img.DecodeParms.WriteString() + "\n"
 	}
 	if img.Filter != nil {
-		s += "/F " + img.Filter.DefaultWriteString() + "\n"
+		s += "/F " + img.Filter.WriteString() + "\n"
 	}
 	if img.Height != nil {
-		s += "/H " + img.Height.DefaultWriteString() + "\n"
+		s += "/H " + img.Height.WriteString() + "\n"
 	}
 	if img.ImageMask != nil {
-		s += "/IM " + img.ImageMask.DefaultWriteString() + "\n"
+		s += "/IM " + img.ImageMask.WriteString() + "\n"
 	}
 	if img.Intent != nil {
-		s += "/Intent " + img.Intent.DefaultWriteString() + "\n"
+		s += "/Intent " + img.Intent.WriteString() + "\n"
 	}
 	if img.Interpolate != nil {
-		s += "/I " + img.Interpolate.DefaultWriteString() + "\n"
+		s += "/I " + img.Interpolate.WriteString() + "\n"
 	}
 	if img.Width != nil {
-		s += "/W " + img.Width.DefaultWriteString() + "\n"
+		s += "/W " + img.Width.WriteString() + "\n"
 	}
 	output.WriteString(s)
 
@@ -198,7 +198,7 @@ func (img *ContentStreamInlineImage) GetEncoder() (core.StreamEncoder, error) {
 	return newEncoderFromInlineImage(img)
 }
 
-// Is a mask ?
+// IsMask checks if an image is a mask.
 // The image mask entry in the image dictionary specifies that the image data shall be used as a stencil
 // mask for painting in the current color. The mask data is 1bpc, grayscale.
 func (img *ContentStreamInlineImage) IsMask() (bool, error) {
@@ -216,7 +216,7 @@ func (img *ContentStreamInlineImage) IsMask() (bool, error) {
 
 }
 
-// Export the inline image to Image which can be transformed or exported easily.
+// ToImage exports the inline image to Image which can be transformed or exported easily.
 // Page resources are needed to look up colorspace information.
 func (img *ContentStreamInlineImage) ToImage(resources *model.PdfPageResources) (*model.Image, error) {
 	// Decode the imaging data if encoded.
@@ -297,7 +297,7 @@ func (img *ContentStreamInlineImage) ToImage(resources *model.PdfPageResources)
 	return image, nil
 }
 
-// Parse an inline image from a content stream, both read its properties and binary data.
+// ParseInlineImage parses an inline image from a content stream, both reading its properties and binary data.
 // When called, "BI" has already been read from the stream.  This function
 // finishes reading through "EI" and then returns the ContentStreamInlineImage.
 func (csp *ContentStreamParser) ParseInlineImage() (*ContentStreamInlineImage, error) {

pdf/contentstream/parser.go

@@ -255,7 +255,7 @@ func (csp *ContentStreamParser) parseNumber() (core.PdfObject, error) {
 func (csp *ContentStreamParser) parseString() (*core.PdfObjectString, error) {
 	csp.reader.ReadByte()
 
-	bytes := []byte{}
+	var bytes []byte
 	count := 1
 	for {
 		bb, err := csp.reader.Peek(1)
@@ -277,7 +277,7 @@ func (csp *ContentStreamParser) parseString() (*core.PdfObjectString, error) {
 					return core.MakeString(string(bytes)), err
 				}
 
-				numeric := []byte{}
+				var numeric []byte
 				numeric = append(numeric, b)
 				for _, val := range bb {
 					if core.IsOctalDigit(val) {
@@ -340,7 +340,7 @@ func (csp *ContentStreamParser) parseHexString() (*core.PdfObjectString, error)
 
 	hextable := []byte("0123456789abcdefABCDEF")
 
-	tmp := []byte{}
+	var tmp []byte
 	for {
 		csp.skipSpaces()
 
@@ -495,7 +495,7 @@ func (csp *ContentStreamParser) parseDict() (*core.PdfObjectDictionary, error) {
 
 // An operand is a text command represented by a word.
 func (csp *ContentStreamParser) parseOperand() (*core.PdfObjectString, error) {
-	bytes := []byte{}
+	var bytes []byte
 	for {
 		bb, err := csp.reader.Peek(1)
 		if err != nil {

pdf/contentstream/processor.go

@@ -13,7 +13,7 @@ import (
 	"github.com/unidoc/unidoc/pdf/model"
 )
 
-// Basic graphics state implementation.
+// GraphicsState is a basic graphics state implementation.
 // Initially only implementing and tracking a portion of the information specified.  Easy to add more.
 type GraphicsState struct {
 	ColorspaceStroking    model.PdfColorspace
@@ -56,12 +56,12 @@ type HandlerEntry struct {
 
 type HandlerConditionEnum int
 
-func (this HandlerConditionEnum) All() bool {
+func (e HandlerConditionEnum) All() bool {
-	return this == HandlerConditionEnumAllOperands
+	return e == HandlerConditionEnumAllOperands
 }
 
-func (this HandlerConditionEnum) Operand() bool {
+func (e HandlerConditionEnum) Operand() bool {
-	return this == HandlerConditionEnumOperand
+	return e == HandlerConditionEnumOperand
 }
 
 const (

pdf/contentstream/utils.go

@@ -14,7 +14,7 @@ import (
 )
 
 func makeParamsFromFloats(vals []float64) []core.PdfObject {
-	params := []core.PdfObject{}
+	var params []core.PdfObject
 	for _, val := range vals {
 		params = append(params, core.MakeFloat(val))
 	}
@@ -22,7 +22,7 @@ func makeParamsFromFloats(vals []float64) []core.PdfObject {
 }
 
 func makeParamsFromNames(vals []core.PdfObjectName) []core.PdfObject {
-	params := []core.PdfObject{}
+	var params []core.PdfObject
 	for _, val := range vals {
 		params = append(params, core.MakeName(string(val)))
 	}
@@ -30,7 +30,7 @@ func makeParamsFromNames(vals []core.PdfObjectName) []core.PdfObject {
 }
 
 func makeParamsFromStrings(vals []core.PdfObjectString) []core.PdfObject {
-	params := []core.PdfObject{}
+	var params []core.PdfObject
 	for _, val := range vals {
 		params = append(params, core.MakeString(val.Str()))
 	}
@@ -38,7 +38,7 @@ func makeParamsFromStrings(vals []core.PdfObjectString) []core.PdfObject {
 }
 
 func makeParamsFromInts(vals []int64) []core.PdfObject {
-	params := []core.PdfObject{}
+	var params []core.PdfObject
 	for _, val := range vals {
 		params = append(params, core.MakeInteger(val))
 	}

pdf/core/crypt.go

@@ -315,7 +315,7 @@ func (crypt *PdfCrypt) loadCryptFilters(ed *PdfObjectDictionary) error {
 	crypt.cryptFilters = cryptFilters{}
 
 	obj := ed.Get("CF")
-	obj = TraceToDirectObject(obj) // XXX may need to resolve reference...
+	obj = TraceToDirectObject(obj) // TODO: may need to resolve reference...
 	if ref, isRef := obj.(*PdfObjectReference); isRef {
 		o, err := crypt.parser.LookupByReference(*ref)
 		if err != nil {

pdf/core/parser.go

@@ -343,7 +343,7 @@ func (parser *PdfParser) parseString() (*PdfObjectString, error) {
 					return MakeString(r.String()), err
 				}
 
-				numeric := []byte{}
+				var numeric []byte
 				numeric = append(numeric, b)
 				for _, val := range bb {
 					if IsOctalDigit(val) {
@@ -595,7 +595,7 @@ func (parser *PdfParser) parseObject() (PdfObject, error) {
 	}
 }
 
-// Reads and parses a PDF dictionary object enclosed with '<<' and '>>'
+// ParseDict reads and parses a PDF dictionary object enclosed with '<<' and '>>'
 // TODO: Unexport (v3).
 func (parser *PdfParser) ParseDict() (*PdfObjectDictionary, error) {
 	common.Log.Trace("Reading PDF Dict!")
@@ -904,7 +904,7 @@ func (parser *PdfParser) parseXrefStream(xstm *PdfObjectInteger) (*PdfObjectDict
 	// Subsections cannot overlap; an object number may have at most
 	// one entry in a section.
 	// Default value: [0 Size].
-	indexList := []int{}
+	var indexList []int
 	if indexObj != nil {
 		common.Log.Trace("Index: %b", indexObj)
 		indicesArray, ok := indexObj.(*PdfObjectArray)
@@ -1241,7 +1241,7 @@ func (parser *PdfParser) loadXrefs() (*PdfObjectDictionary, error) {
 	}
 
 	// Load old objects also.  Only if not already specified.
-	prevList := []int64{}
+	var prevList []int64
 	intInSlice := func(val int64, list []int64) bool {
 		for _, b := range list {
 			if b == val {
@@ -1331,7 +1331,7 @@ func (parser *PdfParser) traceStreamLength(lengthObj PdfObject) (PdfObject, erro
 	return slo, nil
 }
 
-// Parse an indirect object from the input stream. Can also be an object stream.
+// ParseIndirectObject parses an indirect object from the input stream. Can also be an object stream.
 // Returns the indirect object (*PdfIndirectObject) or the stream object (*PdfObjectStream).
 // TODO: Unexport (v3).
 func (parser *PdfParser) ParseIndirectObject() (PdfObject, error) {
@@ -1511,7 +1511,7 @@ func (parser *PdfParser) ParseIndirectObject() (PdfObject, error) {
 	return &indirect, nil
 }
 
-// For testing purposes.
+// NewParserFromString is used for testing purposes.
 // TODO: Unexport (v3) or move to test files, if needed by external test cases.
 func NewParserFromString(txt string) *PdfParser {
 	parser := PdfParser{}

pdf/core/parser_test.go

@@ -92,11 +92,6 @@ func TestNameParsing(t *testing.T) {
 	}
 }
 
-type testStringEntry struct {
-	raw      string
-	expected string
-}
-
 func BenchmarkStringParsing(b *testing.B) {
 	entry := "(Strings may contain balanced parenthesis () and\nspecial characters (*!&}^% and so on).)"
 	parser := makeParserForText(entry)

pdf/core/primitives.go

@@ -17,11 +17,12 @@ import (
 
 // PdfObject is an interface which all primitive PDF objects must implement.
 type PdfObject interface {
-	// Output a string representation of the primitive (for debugging).
+	// String outputs a string representation of the primitive (for debugging).
 	String() string
 
-	// Output the PDF primitive as written to file as expected by the standard.
+	// WriteString outputs the PDF primitive as written to file as expected by the standard.
-	DefaultWriteString() string
+	// TODO(dennwc): it should return a byte slice, or accept a writer
+	WriteString() string
 }
 
 // PdfObjectBool represents the primitive PDF boolean object.
@@ -249,8 +250,8 @@ func (bool *PdfObjectBool) String() string {
 	return "false"
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (bool *PdfObjectBool) DefaultWriteString() string {
+func (bool *PdfObjectBool) WriteString() string {
 	if *bool {
 		return "true"
 	}
@@ -261,8 +262,8 @@ func (int *PdfObjectInteger) String() string {
 	return fmt.Sprintf("%d", *int)
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (int *PdfObjectInteger) DefaultWriteString() string {
+func (int *PdfObjectInteger) WriteString() string {
 	return fmt.Sprintf("%d", *int)
 }
 
@@ -270,8 +271,8 @@ func (float *PdfObjectFloat) String() string {
 	return fmt.Sprintf("%f", *float)
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (float *PdfObjectFloat) DefaultWriteString() string {
+func (float *PdfObjectFloat) WriteString() string {
 	return fmt.Sprintf("%f", *float)
 }
 
@@ -305,8 +306,8 @@ func (str *PdfObjectString) Bytes() []byte {
 	return []byte(str.val)
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (str *PdfObjectString) DefaultWriteString() string {
+func (str *PdfObjectString) WriteString() string {
 	var output bytes.Buffer
 
 	// Handle hex representation.
@@ -350,8 +351,8 @@ func (name *PdfObjectName) String() string {
 	return string(*name)
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (name *PdfObjectName) DefaultWriteString() string {
+func (name *PdfObjectName) WriteString() string {
 	var output bytes.Buffer
 
 	if len(*name) > 127 {
@@ -429,7 +430,7 @@ func (array *PdfObjectArray) Clear() {
 // returned if the array contains non-numeric objects (each element can be either PdfObjectInteger
 // or PdfObjectFloat).
 func (array *PdfObjectArray) ToFloat64Array() ([]float64, error) {
-	vals := []float64{}
+	var vals []float64
 
 	for _, obj := range array.Elements() {
 		switch t := obj.(type) {
@@ -448,7 +449,7 @@ func (array *PdfObjectArray) ToFloat64Array() ([]float64, error) {
 // ToIntegerArray returns a slice of all array elements as an int slice. An error is returned if the
 // array non-integer objects. Each element can only be PdfObjectInteger.
 func (array *PdfObjectArray) ToIntegerArray() ([]int, error) {
-	vals := []int{}
+	var vals []int
 
 	for _, obj := range array.Elements() {
 		if number, is := obj.(*PdfObjectInteger); is {
@@ -464,7 +465,7 @@ func (array *PdfObjectArray) ToIntegerArray() ([]int, error) {
 // ToInt64Slice returns a slice of all array elements as an int64 slice. An error is returned if the
 // array non-integer objects. Each element can only be PdfObjectInteger.
 func (array *PdfObjectArray) ToInt64Slice() ([]int64, error) {
-	vals := []int64{}
+	var vals []int64
 
 	for _, obj := range array.Elements() {
 		if number, is := obj.(*PdfObjectInteger); is {
@@ -490,11 +491,11 @@ func (array *PdfObjectArray) String() string {
 	return outStr
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (array *PdfObjectArray) DefaultWriteString() string {
+func (array *PdfObjectArray) WriteString() string {
 	outStr := "["
 	for ind, o := range array.Elements() {
-		outStr += o.DefaultWriteString()
+		outStr += o.WriteString()
 		if ind < (array.Len() - 1) {
 			outStr += " "
 		}
@@ -567,7 +568,7 @@ func getNumberAsFloatOrNull(obj PdfObject) (*float64, error) {
 // GetAsFloat64Slice returns the array as []float64 slice.
 // Returns an error if not entirely numeric (only PdfObjectIntegers, PdfObjectFloats).
 func (array *PdfObjectArray) GetAsFloat64Slice() ([]float64, error) {
-	slice := []float64{}
+	var slice []float64
 
 	for _, obj := range array.Elements() {
 		number, err := GetNumberAsFloat(TraceToDirectObject(obj))
@@ -601,15 +602,15 @@ func (d *PdfObjectDictionary) String() string {
 	return outStr
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (d *PdfObjectDictionary) DefaultWriteString() string {
+func (d *PdfObjectDictionary) WriteString() string {
 	outStr := "<<"
 	for _, k := range d.keys {
 		v := d.dict[k]
 		common.Log.Trace("Writing k: %s %T %v %v", k, v, k, v)
-		outStr += k.DefaultWriteString()
+		outStr += k.WriteString()
 		outStr += " "
-		outStr += v.DefaultWriteString()
+		outStr += v.WriteString()
 	}
 	outStr += ">>"
 	return outStr
@@ -742,8 +743,8 @@ func (ref *PdfObjectReference) String() string {
 	return fmt.Sprintf("Ref(%d %d)", ref.ObjectNumber, ref.GenerationNumber)
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (ref *PdfObjectReference) DefaultWriteString() string {
+func (ref *PdfObjectReference) WriteString() string {
 	return fmt.Sprintf("%d %d R", ref.ObjectNumber, ref.GenerationNumber)
 }
 
@@ -754,8 +755,8 @@ func (ind *PdfIndirectObject) String() string {
 	return fmt.Sprintf("IObject:%d", (*ind).ObjectNumber)
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (ind *PdfIndirectObject) DefaultWriteString() string {
+func (ind *PdfIndirectObject) WriteString() string {
 	outStr := fmt.Sprintf("%d 0 R", (*ind).ObjectNumber)
 	return outStr
 }
@@ -765,8 +766,8 @@ func (stream *PdfObjectStream) String() string {
 	return fmt.Sprintf("Object stream %d: %s", stream.ObjectNumber, stream.PdfObjectDictionary)
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (stream *PdfObjectStream) DefaultWriteString() string {
+func (stream *PdfObjectStream) WriteString() string {
 	outStr := fmt.Sprintf("%d 0 R", (*stream).ObjectNumber)
 	return outStr
 }
@@ -776,8 +777,8 @@ func (null *PdfObjectNull) String() string {
 	return "null"
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (null *PdfObjectNull) DefaultWriteString() string {
+func (null *PdfObjectNull) WriteString() string {
 	return "null"
 }
 
@@ -876,7 +877,7 @@ func GetStringVal(obj PdfObject) (val string, found bool) {
 	return
 }
 
-// GetStringVal is like GetStringVal except that it returns the string as a []byte.
+// GetStringBytes is like GetStringVal except that it returns the string as a []byte.
 // It is for convenience.
 func GetStringBytes(obj PdfObject) (val []byte, found bool) {
 	so, found := TraceToDirectObject(obj).(*PdfObjectString)
@@ -985,8 +986,8 @@ func (streams *PdfObjectStreams) Len() int {
 	return len(streams.vec)
 }
 
-// DefaultWriteString outputs the object as it is to be written to file.
+// WriteString outputs the object as it is to be written to file.
-func (streams *PdfObjectStreams) DefaultWriteString() string {
+func (streams *PdfObjectStreams) WriteString() string {
 	outStr := fmt.Sprintf("%d 0 R", (*streams).ObjectNumber)
 	return outStr
 }

pdf/core/primitives_test.go

@@ -16,7 +16,7 @@ func TestHexStringWriteBasic(t *testing.T) {
 
 	for src, expected := range testcases {
 		strObj := MakeHexString(src)
-		ws := strObj.DefaultWriteString()
+		ws := strObj.WriteString()
 
 		if ws != expected {
 			t.Fatalf("%s: '%s' != '%s'\n", src, ws, expected)
@@ -39,8 +39,8 @@ func TestHexStringMulti(t *testing.T) {
 		shex := MakeHexString(testcase)
 
 		// Write out.
-		writestr := s.DefaultWriteString()
+		writestr := s.WriteString()
-		writestrhex := shex.DefaultWriteString()
+		writestrhex := shex.WriteString()
 
 		// Parse back.
 		parser1 := makeParserForText(writestr)

pdf/core/utils.go

@@ -38,7 +38,7 @@ func (parser *PdfParser) Inspect() (map[string]int, error) {
 
 // GetObjectNums returns a sorted list of object numbers of the PDF objects in the file.
 func (parser *PdfParser) GetObjectNums() []int {
-	objNums := []int{}
+	var objNums []int
 	for _, x := range parser.xrefs {
 		objNums = append(objNums, x.ObjectNumber)
 	}
@@ -67,7 +67,7 @@ func (parser *PdfParser) inspect() (map[string]int, error) {
 	objCount := 0
 	failedCount := 0
 
-	keys := []int{}
+	var keys []int
 	for k := range parser.xrefs {
 		keys = append(keys, k)
 	}

pdf/creator/block.go

@@ -126,7 +126,7 @@ func (blk *Block) duplicate() *Block {
 // GeneratePageBlocks draws the block contents on a template Page block.
 // Implements the Drawable interface.
 func (blk *Block) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, error) {
-	blocks := []*Block{}
+	var blocks []*Block
 
 	if blk.positioning.isRelative() {
 		// Draw at current ctx.X, ctx.Y position
@@ -135,7 +135,7 @@ func (blk *Block) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, er
 		cc.Translate(ctx.X, ctx.PageHeight-ctx.Y-blk.height)
 		if blk.angle != 0 {
 			// Make the rotation about the upper left corner.
-			// XXX/TODO: Account for rotation origin. (Consider).
+			// TODO: Account for rotation origin. (Consider).
 			cc.Translate(0, blk.Height())
 			cc.RotateDeg(blk.angle)
 			cc.Translate(0, -blk.Height())
@@ -154,7 +154,7 @@ func (blk *Block) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, er
 		cc.Translate(blk.xPos, ctx.PageHeight-blk.yPos-blk.height)
 		if blk.angle != 0 {
 			// Make the rotation about the upper left corner.
-			// XXX/TODO: Consider supporting specification of rotation origin.
+			// TODO: Consider supporting specification of rotation origin.
 			cc.Translate(0, blk.Height())
 			cc.RotateDeg(blk.angle)
 			cc.Translate(0, -blk.Height())

pdf/creator/creator.go

@@ -399,7 +399,7 @@ func (c *Creator) finalize() error {
 		}
 
 		blocks, _, _ := c.toc.GeneratePageBlocks(c.context)
-		tocpages := []*model.PdfPage{}
+		var tocpages []*model.PdfPage
 		for _, block := range blocks {
 			block.SetPos(0, 0)
 			totPages++

pdf/creator/creator_test.go

@@ -60,7 +60,7 @@ const testRobotoRegularTTFFile = "./testdata/roboto/Roboto-Regular.ttf"
 const testRobotoBoldTTFFile = "./testdata/roboto/Roboto-Bold.ttf"
 const testWts11TTFFile = "./testdata/wts11.ttf"
 
-// XXX(peterwilliams97): /tmp/2_p_multi.pdf which is created in this test gives an error message
+// TODO(peterwilliams97): /tmp/2_p_multi.pdf which is created in this test gives an error message
 //      when opened in Adobe Reader: The font FreeSans contains bad Widths.
 //      This problem did not occur when I replaced FreeSans.ttf with LiberationSans-Regular.ttf
 const testFreeSansTTFFile = "./testdata/FreeSans.ttf"

pdf/creator/division.go

@@ -103,7 +103,7 @@ func (div *Division) Width() float64 {
 // GeneratePageBlocks generates the page blocks for the Division component.
 // Multiple blocks are generated if the contents wrap over multiple pages.
 func (div *Division) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, error) {
-	pageblocks := []*Block{}
+	var pageblocks []*Block
 
 	origCtx := ctx
 

pdf/creator/drawable.go

@@ -7,7 +7,7 @@ package creator
 
 // Drawable is a widget that can be used to draw with the Creator.
 type Drawable interface {
-	// Draw onto blocks representing Page contents. As the content can wrap over many pages, multiple
+	// GeneratePageBlocks draw onto blocks representing Page contents. As the content can wrap over many pages, multiple
 	// templates are returned, one per Page.  The function also takes a draw context containing information
 	// where to draw (if relative positioning) and the available height to draw on accounting for Margins etc.
 	GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, error)

pdf/creator/image.go

@@ -168,7 +168,7 @@ func (img *Image) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, er
 		img.makeXObject()
 	}
 
-	blocks := []*Block{}
+	var blocks []*Block
 	origCtx := ctx
 
 	blk := NewBlock(ctx.PageWidth, ctx.PageHeight)
@@ -212,7 +212,7 @@ func (img *Image) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, er
 		// Absolute drawing should not affect context.
 		ctx = origCtx
 	} else {
-		// XXX/TODO: Use projected height.
+		// TODO: Use projected height.
 		ctx.Y += img.margins.bottom
 		ctx.Height -= img.margins.bottom
 	}

pdf/creator/paragraph.go

@@ -69,6 +69,8 @@ type Paragraph struct {
 // newParagraph create a new text paragraph. Uses default parameters: Helvetica, WinAnsiEncoding and
 // wrap enabled with a wrap width of 100 points.
 func newParagraph(text string, style TextStyle) *Paragraph {
+	// TODO(dennwc): style is unused
+
 	p := &Paragraph{}
 	p.text = text
 
@@ -215,7 +217,7 @@ func (p *Paragraph) getTextWidth() float64 {
 		glyph, found := p.textFont.Encoder().RuneToGlyph(r)
 		if !found {
 			common.Log.Debug("ERROR: Glyph not found for rune: 0x%04x=%c", r, r)
-			return -1 // XXX/FIXME: return error.
+			return -1 // FIXME: return error.
 		}
 
 		// Ignore newline for this.. Handles as if all in one line.
@@ -226,7 +228,7 @@ func (p *Paragraph) getTextWidth() float64 {
 		metrics, found := p.textFont.GetGlyphCharMetrics(glyph)
 		if !found {
 			common.Log.Debug("ERROR: Glyph char metrics not found! %q (rune 0x%04x=%c)", glyph, r, r)
-			return -1 // XXX/FIXME: return error.
+			return -1 // FIXME: return error.
 		}
 		w += p.fontSize * metrics.Wx
 	}
@@ -241,7 +243,7 @@ func (p *Paragraph) getTextLineWidth(line string) float64 {
 		glyph, found := p.textFont.Encoder().RuneToGlyph(r)
 		if !found {
 			common.Log.Debug("ERROR: Glyph not found for rune: 0x%04x=%c", r, r)
-			return -1 // XXX/FIXME: return error.
+			return -1 // FIXME: return error.
 		}
 
 		// Ignore newline for this.. Handles as if all in one line.
@@ -252,7 +254,7 @@ func (p *Paragraph) getTextLineWidth(line string) float64 {
 		metrics, found := p.textFont.GetGlyphCharMetrics(glyph)
 		if !found {
 			common.Log.Debug("ERROR: Glyph char metrics not found! %q (rune 0x%04x=%c)", glyph, r, r)
-			return -1 // XXX/FIXME: return error.
+			return -1 // FIXME: return error.
 		}
 
 		width += p.fontSize * metrics.Wx
@@ -279,7 +281,7 @@ func (p *Paragraph) getMaxLineWidth() float64 {
 }
 
 // Simple algorithm to wrap the text into lines (greedy algorithm - fill the lines).
-// XXX/TODO: Consider the Knuth/Plass algorithm or an alternative.
+// TODO: Consider the Knuth/Plass algorithm or an alternative.
 func (p *Paragraph) wrapText() error {
 	if !p.enableWrap || int(p.wrapWidth) <= 0 {
 		p.textLines = []string{p.text}
@@ -329,7 +331,7 @@ func (p *Paragraph) wrapText() error {
 			// Breaks on the character.
 			idx := -1
 			for i := len(glyphs) - 1; i >= 0; i-- {
-				if glyphs[i] == "space" { // XXX: What about other space glyphs like controlHT?
+				if glyphs[i] == "space" { // TODO: What about other space glyphs like controlHT?
 					idx = i
 					break
 				}
@@ -378,7 +380,7 @@ func sum(widths []float64) float64 {
 // over multiple pages. Implements the Drawable interface.
 func (p *Paragraph) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, error) {
 	origContext := ctx
-	blocks := []*Block{}
+	var blocks []*Block
 
 	blk := NewBlock(ctx.PageWidth, ctx.PageHeight)
 	if p.positioning.isRelative() {
@@ -394,7 +396,7 @@ func (p *Paragraph) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext,
 		if p.Height() > ctx.Height {
 			// Goes out of the bounds.  Write on a new template instead and create a new context at
 			// upper left corner.
-			// XXX/TODO: Handle case when Paragraph is larger than the Page...
+			// TODO: Handle case when Paragraph is larger than the Page...
 			// Should be fine if we just break on the paragraph, i.e. splitting it up over 2+ pages
 
 			blocks = append(blocks, blk)
@@ -507,7 +509,7 @@ func drawParagraphOnBlock(blk *Block, p *Paragraph, ctx DrawContext) (DrawContex
 			w += p.fontSize * metrics.Wx
 		}
 
-		objs := []core.PdfObject{}
+		var objs []core.PdfObject
 
 		spaceMetrics, found := p.textFont.GetGlyphCharMetrics("space")
 		if !found {
@@ -530,7 +532,7 @@ func drawParagraphOnBlock(blk *Block, p *Paragraph, ctx DrawContext) (DrawContex
 			objs = append(objs, core.MakeFloat(-shift))
 		}
 
-		encoded := []byte{}
+		var encoded []byte
 		isCID := p.textFont.IsCID()
 		for _, r := range runes {
 			glyph, ok := p.textFont.Encoder().RuneToGlyph(r)
@@ -539,7 +541,7 @@ func drawParagraphOnBlock(blk *Block, p *Paragraph, ctx DrawContext) (DrawContex
 				return ctx, errors.New("Unsupported rune in text encoding")
 			}
 
-			if glyph == "space" { // XXX: What about \t and other spaces.
+			if glyph == "space" { // TODO: What about \t and other spaces.
 				if len(encoded) > 0 {
 					objs = append(objs, core.MakeStringFromBytes(encoded))
 					encoded = []byte{}

pdf/creator/styled_paragraph.go

@@ -238,7 +238,7 @@ func (p *StyledParagraph) getTextWidth() float64 {
 			if !found {
 				common.Log.Debug("Error! Glyph not found for rune: %s\n", rune)
 
-				// XXX/FIXME: return error.
+				// FIXME: return error.
 				return -1
 			}
 
@@ -251,7 +251,7 @@ func (p *StyledParagraph) getTextWidth() float64 {
 			if !found {
 				common.Log.Debug("Glyph char metrics not found! %s\n", glyph)
 
-				// XXX/FIXME: return error.
+				// FIXME: return error.
 				return -1
 			}
 
@@ -273,7 +273,7 @@ func (p *StyledParagraph) getTextLineWidth(line []*TextChunk) float64 {
 			if !found {
 				common.Log.Debug("Error! Glyph not found for rune: %s\n", r)
 
-				// XXX/FIXME: return error.
+				// FIXME: return error.
 				return -1
 			}
 
@@ -286,7 +286,7 @@ func (p *StyledParagraph) getTextLineWidth(line []*TextChunk) float64 {
 			if !found {
 				common.Log.Debug("Glyph char metrics not found! %s\n", glyph)
 
-				// XXX/FIXME: return error.
+				// FIXME: return error.
 				return -1
 			}
 
@@ -329,7 +329,7 @@ func (p *StyledParagraph) getTextHeight() float64 {
 
 // wrapText splits text into lines. It uses a simple greedy algorithm to wrap
 // fill the lines.
-// XXX/TODO: Consider the Knuth/Plass algorithm or an alternative.
+// TODO: Consider the Knuth/Plass algorithm or an alternative.
 func (p *StyledParagraph) wrapText() error {
 	if !p.enableWrap || int(p.wrapWidth) <= 0 {
 		p.lines = [][]*TextChunk{p.chunks}
@@ -362,7 +362,7 @@ func (p *StyledParagraph) wrapText() error {
 			if !found {
 				common.Log.Debug("Error! Glyph not found for rune: %v\n", r)
 
-				// XXX/FIXME: return error.
+				// FIXME: return error.
 				return errors.New("Glyph not found for rune")
 			}
 
@@ -387,8 +387,6 @@ func (p *StyledParagraph) wrapText() error {
 			metrics, found := style.Font.GetGlyphCharMetrics(glyph)
 			if !found {
 				common.Log.Debug("Glyph char metrics not found! %s\n", glyph)
-
-				// XXX/FIXME: return error.
 				return errors.New("Glyph char metrics missing")
 			}
 
@@ -396,7 +394,7 @@ func (p *StyledParagraph) wrapText() error {
 			if lineWidth+w > p.wrapWidth*1000.0 {
 				// Goes out of bounds: Wrap.
 				// Breaks on the character.
-				// XXX/TODO: when goes outside: back up to next space,
+				// TODO: when goes outside: back up to next space,
 				// otherwise break on the character.
 				idx := -1
 				for j := len(glyphs) - 1; j >= 0; j-- {
@@ -463,7 +461,7 @@ func (p *StyledParagraph) wrapText() error {
 // if the contents wrap over multiple pages. Implements the Drawable interface.
 func (p *StyledParagraph) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, error) {
 	origContext := ctx
-	blocks := []*Block{}
+	var blocks []*Block
 
 	blk := NewBlock(ctx.PageWidth, ctx.PageHeight)
 	if p.positioning.isRelative() {
@@ -479,7 +477,7 @@ func (p *StyledParagraph) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawCon
 		if p.Height() > ctx.Height {
 			// Goes out of the bounds.  Write on a new template instead and create a new context at upper
 			// left corner.
-			// XXX/TODO: Handle case when Paragraph is larger than the Page...
+			// TODO: Handle case when Paragraph is larger than the Page...
 			// Should be fine if we just break on the paragraph, i.e. splitting it up over 2+ pages
 
 			blocks = append(blocks, blk)
@@ -549,10 +547,10 @@ func drawStyledParagraphOnBlock(blk *Block, p *StyledParagraph, ctx DrawContext)
 	p.wrapText()
 
 	// Add the fonts of all chunks to the page resources.
-	fonts := [][]core.PdfObjectName{}
+	var fonts [][]core.PdfObjectName
 
 	for _, line := range p.lines {
-		fontLine := []core.PdfObjectName{}
+		var fontLine []core.PdfObjectName
 
 		for _, chunk := range line {
 			fontName = core.PdfObjectName(fmt.Sprintf("Font%d", num))
@@ -647,7 +645,7 @@ func drawStyledParagraphOnBlock(blk *Block, p *StyledParagraph, ctx DrawContext)
 		height *= p.lineHeight
 
 		// Add line shifts.
-		objs := []core.PdfObject{}
+		var objs []core.PdfObject
 
 		wrapWidth := p.wrapWidth * 1000.0
 		if p.alignment == TextAlignmentJustify {

pdf/creator/table.go

@@ -65,7 +65,7 @@ func newTable(cols int) *Table {
 	t.rowHeights = []float64{}
 
 	// Default row height
-	// XXX/TODO: Base on contents instead?
+	// TODO: Base on contents instead?
 	t.defaultRowHeight = 10.0
 
 	t.cells = []*TableCell{}
@@ -152,7 +152,7 @@ func (table *Table) SetPos(x, y float64) {
 // over multiple pages.
 // Implements the Drawable interface.
 func (table *Table) GeneratePageBlocks(ctx DrawContext) ([]*Block, DrawContext, error) {
-	blocks := []*Block{}
+	var blocks []*Block
 	block := NewBlock(ctx.PageWidth, ctx.PageHeight)
 
 	origCtx := ctx
@@ -468,10 +468,10 @@ type CellBorderStyle int
 
 // Currently supported table styles are: None (no border) and boxed (line along each side).
 const (
-	// No border
+	CellBorderStyleNone CellBorderStyle = iota // no border
-	CellBorderStyleNone CellBorderStyle = iota
 
 	// Borders along all sides (boxed).
+
 	CellBorderStyleSingle
 	CellBorderStyleDouble
 )
@@ -501,13 +501,13 @@ type CellHorizontalAlignment int
 
 // Table cells have three horizontal alignment modes: left, center and right.
 const (
-	// Align cell content on the left (with specified indent); unused space on the right.
+	// CellHorizontalAlignmentLeft aligns cell content on the left (with specified indent); unused space on the right.
 	CellHorizontalAlignmentLeft CellHorizontalAlignment = iota
 
-	// Align cell content in the middle (unused space divided equally on the left/right).
+	// CellHorizontalAlignmentCenter aligns cell content in the middle (unused space divided equally on the left/right).
 	CellHorizontalAlignmentCenter
 
-	// Align the cell content on the right; unsued space on the left.
+	// CellHorizontalAlignmentRight aligns the cell content on the right; unsued space on the left.
 	CellHorizontalAlignmentRight
 )
 
@@ -516,13 +516,13 @@ type CellVerticalAlignment int
 
 // Table cells have three vertical alignment modes: top, middle and bottom.
 const (
-	// Align cell content vertically to the top; unused space below.
+	// CellVerticalAlignmentTop aligns cell content vertically to the top; unused space below.
 	CellVerticalAlignmentTop CellVerticalAlignment = iota
 
-	// Align cell content in the middle; unused space divided equally above and below.
+	// CellVerticalAlignmentMiddle aligns cell content in the middle; unused space divided equally above and below.
 	CellVerticalAlignmentMiddle
 
-	// Align cell content on the bottom; unused space above.
+	// CellVerticalAlignmentBottom aligns cell content on the bottom; unused space above.
 	CellVerticalAlignmentBottom
 )
 

pdf/creator/toc_line.go

@@ -156,11 +156,11 @@ func (tl *TOCLine) prepareParagraph(sp *StyledParagraph, ctx DrawContext) {
 
 	sp.chunks = []*TextChunk{
 		&tl.Number,
-		&TextChunk{
+		{
 			Text:  title,
 			Style: tl.Title.Style,
 		},
-		&TextChunk{
+		{
 			Text:  page,
 			Style: tl.Page.Style,
 		},

pdf/creator/utils.go

@@ -31,7 +31,7 @@ func loadPagesFromFile(path string) ([]*model.PdfPage, error) {
 	}
 
 	// Load the pages.
-	pages := []*model.PdfPage{}
+	var pages []*model.PdfPage
 	for i := 0; i < numPages; i++ {
 		page, err := pdfReader.GetPage(i + 1)
 		if err != nil {

pdf/extractor/text.go

@@ -380,7 +380,7 @@ func (to *textObject) setFont(name string, size float64) error {
 			(*to.fontStack)[len(*to.fontStack)-1] = font
 		}
 	} else if err == model.ErrFontNotSupported {
-		// XXX: Do we need to handle this case in a special way?
+		// TODO: Do we need to handle this case in a special way?
 		return err
 	} else {
 		return err
@@ -644,7 +644,7 @@ func (to *textObject) getFont(name string) (*model.PdfFont, error) {
 
 		// Eject a victim if the cache is full.
 		if len(to.e.fontCache) >= maxFontCache {
-			names := []string{}
+			var names []string
 			for name := range to.e.fontCache {
 				names = append(names, name)
 			}

pdf/fdf/fielddata.go

@@ -80,7 +80,7 @@ func (fdf *Data) FieldValues() (map[string]core.PdfObject, error) {
 		return nil, err
 	}
 
-	keys := []string{}
+	var keys []string
 	for fieldName := range fieldDictMap {
 		keys = append(keys, fieldName)
 	}

pdf/fdf/parser.go

@@ -28,7 +28,6 @@ var reNumeric = regexp.MustCompile(`^[\+-.]*([0-9.]+)`)
 var reExponential = regexp.MustCompile(`^[\+-.]*([0-9.]+)e[\+-.]*([0-9.]+)`)
 var reReference = regexp.MustCompile(`^\s*(\d+)\s+(\d+)\s+R`)
 var reIndirectObject = regexp.MustCompile(`(\d+)\s+(\d+)\s+obj`)
-var reTrailer = regexp.MustCompile(`trailer`)
 
 // fdfParser parses a FDF file and provides access to the object structure of the FDF.
 type fdfParser struct {

pdf/internal/cmap/cmap.go

@@ -68,7 +68,7 @@ func NewToUnicodeCMap(codeToUnicode map[CharCode]rune) *CMap {
 			Ordering:   "UCS",
 			Supplement: 0,
 		},
-		codespaces:    []Codespace{Codespace{Low: 0, High: 0xffff}},
+		codespaces:    []Codespace{{Low: 0, High: 0xffff}},
 		codeToUnicode: codeToUnicode,
 	}
 }
@@ -318,14 +318,14 @@ func (cmap *CMap) toBfData() string {
 	}
 
 	// codes is a sorted list of the codeToUnicode keys.
-	codes := []CharCode{}
+	var codes []CharCode
 	for code := range cmap.codeToUnicode {
 		codes = append(codes, code)
 	}
 	sort.Slice(codes, func(i, j int) bool { return codes[i] < codes[j] })
 
 	// charRanges is a list of the contiguous character code ranges in `codes`.
-	charRanges := []charRange{}
+	var charRanges []charRange
 	c0, c1 := codes[0], codes[0]+1
 	for _, c := range codes[1:] {
 		if c != c1 {
@@ -339,8 +339,8 @@ func (cmap *CMap) toBfData() string {
 	}
 
 	// fbChars is a list of single character ranges. fbRanges is a list of multiple character ranges.
-	fbChars := []CharCode{}
+	var fbChars []CharCode
-	fbRanges := []fbRange{}
+	var fbRanges []fbRange
 	for _, cr := range charRanges {
 		if cr.code0+1 == cr.code1 {
 			fbChars = append(fbChars, cr.code0)
@@ -355,7 +355,7 @@ func (cmap *CMap) toBfData() string {
 	common.Log.Trace("charRanges=%d fbChars=%d fbRanges=%d", len(charRanges), len(fbChars),
 		len(fbRanges))
 
-	lines := []string{}
+	var lines []string
 	if len(fbChars) > 0 {
 		numRanges := (len(fbChars) + maxBfEntries - 1) / maxBfEntries
 		for i := 0; i < numRanges; i++ {

pdf/internal/cmap/cmap_test.go

@@ -672,12 +672,12 @@ func checkCmapWriteRead(t *testing.T, codeToUnicode map[CharCode]rune) {
 		return
 	}
 
-	codes0 := []CharCode{}
+	codes0 := make([]CharCode, 0, len(codeToUnicode))
 	for code := range codeToUnicode {
 		codes0 = append(codes0, code)
 	}
 	sort.Slice(codes0, func(i, j int) bool { return codes0[i] < codes0[j] })
-	codes := []CharCode{}
+	codes := make([]CharCode, 0, len(cmap.codeToUnicode))
 	for code := range cmap.codeToUnicode {
 		codes = append(codes, code)
 	}

pdf/internal/cmap/const.go

@@ -7,7 +7,6 @@ package cmap
 
 import (
 	"errors"
-	"regexp"
 )
 
 var (
@@ -34,5 +33,3 @@ const (
 	cmaptype    = "CMapType"
 	cmapversion = "CMapVersion"
 )
-
-var reNumeric = regexp.MustCompile(`^[\+-.]*([0-9.]+)`)

pdf/internal/cmap/parser.go

@@ -203,7 +203,7 @@ func (p *cMapParser) parseString() (cmapString, error) {
 					return cmapString{buf.String()}, err
 				}
 
-				numeric := []byte{}
+				var numeric []byte
 				numeric = append(numeric, b)
 				for _, val := range bb {
 					if core.IsOctalDigit(val) {

pdf/internal/sampling/resample.go

@@ -5,10 +5,10 @@
 
 package sampling
 
-// Resample the raw data which is in 8-bit (byte) format as a different
+// ResampleBytes resamples the raw data which is in 8-bit (byte) format as a different
 // bit count per sample, up to 32 bits (uint32).
 func ResampleBytes(data []byte, bitsPerSample int) []uint32 {
-	samples := []uint32{}
+	var samples []uint32
 
 	bitsLeftPerSample := bitsPerSample
 	var sample uint32
@@ -96,13 +96,13 @@ func ResampleBytes(data []byte, bitsPerSample int) []uint32 {
 	return samples
 }
 
-// Resample the raw data which is in <=32-bit (uint32) format as a different
+// ResampleUint32 resamples the raw data which is in <=32-bit (uint32) format as a different
 // bit count per sample, up to 32 bits (uint32).
 //
 // bitsPerOutputSample is the number of bits for each output sample (up to 32)
 // bitsPerInputSample is the number of bits used in each input sample (up to 32)
 func ResampleUint32(data []uint32, bitsPerInputSample int, bitsPerOutputSample int) []uint32 {
-	samples := []uint32{}
+	var samples []uint32
 
 	bitsLeftPerSample := bitsPerOutputSample
 	var sample uint32

pdf/internal/strutils/encoding.go

@@ -60,7 +60,7 @@ func StringToUTF16(s string) string {
 
 // PDFDocEncodingToRunes decodes PDFDocEncoded byte slice `b` to unicode runes.
 func PDFDocEncodingToRunes(b []byte) []rune {
-	runes := []rune{}
+	var runes []rune
 	for _, bval := range b {
 		rune, has := pdfDocEncoding[bval]
 		if !has {

pdf/internal/testutils/testutils.go

@@ -86,7 +86,7 @@ func resolveReferences(obj core.PdfObject, objmap map[int64]core.PdfObject) erro
 func CompareDictionariesDeep(d1, d2 *core.PdfObjectDictionary) bool {
 	if len(d1.Keys()) != len(d2.Keys()) {
 		common.Log.Debug("Dict entries mismatch (%d != %d)", len(d1.Keys()), len(d2.Keys()))
-		common.Log.Debug("Was '%s' vs '%s'", d1.DefaultWriteString(), d2.DefaultWriteString())
+		common.Log.Debug("Was '%s' vs '%s'", d1.WriteString(), d2.WriteString())
 		return false
 	}
 
@@ -140,8 +140,8 @@ func CompareDictionariesDeep(d1, d2 *core.PdfObjectDictionary) bool {
 						return false
 					}
 				} else {
-					if v1.DefaultWriteString() != v2.DefaultWriteString() {
+					if v1.WriteString() != v2.WriteString() {
-						common.Log.Debug("Mismatch '%s' != '%s'", v1.DefaultWriteString(), v2.DefaultWriteString())
+						common.Log.Debug("Mismatch '%s' != '%s'", v1.WriteString(), v2.WriteString())
 						return false
 					}
 				}

pdf/internal/textencoding/cmap.go

@@ -26,7 +26,7 @@ func (cmap CMapIdentityH) CharacterCodesToCID(raw []byte) ([]CID, error) {
 		return nil, core.ErrRangeError
 	}
 
-	cids := []CID{}
+	var cids []CID
 	for i := 0; i < len(raw); i += 2 {
 		b1 := CID(raw[i])
 		b2 := CID(raw[i+1])

pdf/internal/textencoding/glyphs_glyphlist.go

@@ -21,14 +21,14 @@ import (
 const MissingCodeRune = '\ufffd' // <20>
 
 // GlyphToRune returns the rune corresponding to glyph `glyph` if there is one.
-// XXX: TODO: Can we return a string here? e.g. When we are extracting text, we want to get "ffi"
+// TODO: Can we return a string here? e.g. When we are extracting text, we want to get "ffi"
-//            rather than 'ffi'. We only need a glyph ➞ rune map when we need to convert back to
+//       rather than 'ffi'. We only need a glyph ➞ rune map when we need to convert back to
-//            glyphs.
+//       glyphs.
-//            We are currently applying RuneToString to the output of functions that call
+//       We are currently applying RuneToString to the output of functions that call
-//            GlyphToRune. While this gives the same result, it makes the calling code complex and
+//       GlyphToRune. While this gives the same result, it makes the calling code complex and
-//            fragile.
+//       fragile.
-// XXX: TODO: Can we combine all the tables glyphAliases, glyphlistGlyphToRuneMap,
+// TODO: Can we combine all the tables glyphAliases, glyphlistGlyphToRuneMap,
-//            texGlyphlistGlyphToStringMap, additionalGlyphlistGlyphToRuneMap and ".notdef"?
+//       texGlyphlistGlyphToStringMap, additionalGlyphlistGlyphToRuneMap and ".notdef"?
 func GlyphToRune(glyph GlyphName) (rune, bool) {
 	// We treat glyph "eight.lf" the same as glyph "eight".
 	// See contrib/testdata/font/Ingmar.txt