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-rw-r--r--src/encoding/csv/example_test.go131
-rw-r--r--src/encoding/csv/fuzz.go70
-rw-r--r--src/encoding/csv/reader.go450
-rw-r--r--src/encoding/csv/reader_test.go650
-rw-r--r--src/encoding/csv/writer.go181
-rw-r--r--src/encoding/csv/writer_test.go112
6 files changed, 1594 insertions, 0 deletions
diff --git a/src/encoding/csv/example_test.go b/src/encoding/csv/example_test.go
new file mode 100644
index 0000000..dc227d4
--- /dev/null
+++ b/src/encoding/csv/example_test.go
@@ -0,0 +1,131 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package csv_test
+
+import (
+ "encoding/csv"
+ "fmt"
+ "io"
+ "log"
+ "os"
+ "strings"
+)
+
+func ExampleReader() {
+ in := `first_name,last_name,username
+"Rob","Pike",rob
+Ken,Thompson,ken
+"Robert","Griesemer","gri"
+`
+ r := csv.NewReader(strings.NewReader(in))
+
+ for {
+ record, err := r.Read()
+ if err == io.EOF {
+ break
+ }
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ fmt.Println(record)
+ }
+ // Output:
+ // [first_name last_name username]
+ // [Rob Pike rob]
+ // [Ken Thompson ken]
+ // [Robert Griesemer gri]
+}
+
+// This example shows how csv.Reader can be configured to handle other
+// types of CSV files.
+func ExampleReader_options() {
+ in := `first_name;last_name;username
+"Rob";"Pike";rob
+# lines beginning with a # character are ignored
+Ken;Thompson;ken
+"Robert";"Griesemer";"gri"
+`
+ r := csv.NewReader(strings.NewReader(in))
+ r.Comma = ';'
+ r.Comment = '#'
+
+ records, err := r.ReadAll()
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ fmt.Print(records)
+ // Output:
+ // [[first_name last_name username] [Rob Pike rob] [Ken Thompson ken] [Robert Griesemer gri]]
+}
+
+func ExampleReader_ReadAll() {
+ in := `first_name,last_name,username
+"Rob","Pike",rob
+Ken,Thompson,ken
+"Robert","Griesemer","gri"
+`
+ r := csv.NewReader(strings.NewReader(in))
+
+ records, err := r.ReadAll()
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ fmt.Print(records)
+ // Output:
+ // [[first_name last_name username] [Rob Pike rob] [Ken Thompson ken] [Robert Griesemer gri]]
+}
+
+func ExampleWriter() {
+ records := [][]string{
+ {"first_name", "last_name", "username"},
+ {"Rob", "Pike", "rob"},
+ {"Ken", "Thompson", "ken"},
+ {"Robert", "Griesemer", "gri"},
+ }
+
+ w := csv.NewWriter(os.Stdout)
+
+ for _, record := range records {
+ if err := w.Write(record); err != nil {
+ log.Fatalln("error writing record to csv:", err)
+ }
+ }
+
+ // Write any buffered data to the underlying writer (standard output).
+ w.Flush()
+
+ if err := w.Error(); err != nil {
+ log.Fatal(err)
+ }
+ // Output:
+ // first_name,last_name,username
+ // Rob,Pike,rob
+ // Ken,Thompson,ken
+ // Robert,Griesemer,gri
+}
+
+func ExampleWriter_WriteAll() {
+ records := [][]string{
+ {"first_name", "last_name", "username"},
+ {"Rob", "Pike", "rob"},
+ {"Ken", "Thompson", "ken"},
+ {"Robert", "Griesemer", "gri"},
+ }
+
+ w := csv.NewWriter(os.Stdout)
+ w.WriteAll(records) // calls Flush internally
+
+ if err := w.Error(); err != nil {
+ log.Fatalln("error writing csv:", err)
+ }
+ // Output:
+ // first_name,last_name,username
+ // Rob,Pike,rob
+ // Ken,Thompson,ken
+ // Robert,Griesemer,gri
+}
diff --git a/src/encoding/csv/fuzz.go b/src/encoding/csv/fuzz.go
new file mode 100644
index 0000000..5f5cdfc
--- /dev/null
+++ b/src/encoding/csv/fuzz.go
@@ -0,0 +1,70 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build gofuzz
+
+package csv
+
+import (
+ "bytes"
+ "fmt"
+ "reflect"
+)
+
+func Fuzz(data []byte) int {
+ score := 0
+ buf := new(bytes.Buffer)
+
+ for _, tt := range []Reader{
+ {},
+ {Comma: ';'},
+ {Comma: '\t'},
+ {LazyQuotes: true},
+ {TrimLeadingSpace: true},
+ {Comment: '#'},
+ {Comment: ';'},
+ } {
+ r := NewReader(bytes.NewReader(data))
+ r.Comma = tt.Comma
+ r.Comment = tt.Comment
+ r.LazyQuotes = tt.LazyQuotes
+ r.TrimLeadingSpace = tt.TrimLeadingSpace
+
+ records, err := r.ReadAll()
+ if err != nil {
+ continue
+ }
+ score = 1
+
+ buf.Reset()
+ w := NewWriter(buf)
+ w.Comma = tt.Comma
+ err = w.WriteAll(records)
+ if err != nil {
+ fmt.Printf("writer = %#v\n", w)
+ fmt.Printf("records = %v\n", records)
+ panic(err)
+ }
+
+ r = NewReader(buf)
+ r.Comma = tt.Comma
+ r.Comment = tt.Comment
+ r.LazyQuotes = tt.LazyQuotes
+ r.TrimLeadingSpace = tt.TrimLeadingSpace
+ result, err := r.ReadAll()
+ if err != nil {
+ fmt.Printf("reader = %#v\n", r)
+ fmt.Printf("records = %v\n", records)
+ panic(err)
+ }
+
+ if !reflect.DeepEqual(records, result) {
+ fmt.Println("records = \n", records)
+ fmt.Println("result = \n", records)
+ panic("not equal")
+ }
+ }
+
+ return score
+}
diff --git a/src/encoding/csv/reader.go b/src/encoding/csv/reader.go
new file mode 100644
index 0000000..f860f4f
--- /dev/null
+++ b/src/encoding/csv/reader.go
@@ -0,0 +1,450 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package csv reads and writes comma-separated values (CSV) files.
+// There are many kinds of CSV files; this package supports the format
+// described in RFC 4180.
+//
+// A csv file contains zero or more records of one or more fields per record.
+// Each record is separated by the newline character. The final record may
+// optionally be followed by a newline character.
+//
+// field1,field2,field3
+//
+// White space is considered part of a field.
+//
+// Carriage returns before newline characters are silently removed.
+//
+// Blank lines are ignored. A line with only whitespace characters (excluding
+// the ending newline character) is not considered a blank line.
+//
+// Fields which start and stop with the quote character " are called
+// quoted-fields. The beginning and ending quote are not part of the
+// field.
+//
+// The source:
+//
+// normal string,"quoted-field"
+//
+// results in the fields
+//
+// {`normal string`, `quoted-field`}
+//
+// Within a quoted-field a quote character followed by a second quote
+// character is considered a single quote.
+//
+// "the ""word"" is true","a ""quoted-field"""
+//
+// results in
+//
+// {`the "word" is true`, `a "quoted-field"`}
+//
+// Newlines and commas may be included in a quoted-field
+//
+// "Multi-line
+// field","comma is ,"
+//
+// results in
+//
+// {`Multi-line
+// field`, `comma is ,`}
+package csv
+
+import (
+ "bufio"
+ "bytes"
+ "errors"
+ "fmt"
+ "io"
+ "unicode"
+ "unicode/utf8"
+)
+
+// A ParseError is returned for parsing errors.
+// Line numbers are 1-indexed and columns are 0-indexed.
+type ParseError struct {
+ StartLine int // Line where the record starts
+ Line int // Line where the error occurred
+ Column int // Column (1-based byte index) where the error occurred
+ Err error // The actual error
+}
+
+func (e *ParseError) Error() string {
+ if e.Err == ErrFieldCount {
+ return fmt.Sprintf("record on line %d: %v", e.Line, e.Err)
+ }
+ if e.StartLine != e.Line {
+ return fmt.Sprintf("record on line %d; parse error on line %d, column %d: %v", e.StartLine, e.Line, e.Column, e.Err)
+ }
+ return fmt.Sprintf("parse error on line %d, column %d: %v", e.Line, e.Column, e.Err)
+}
+
+func (e *ParseError) Unwrap() error { return e.Err }
+
+// These are the errors that can be returned in ParseError.Err.
+var (
+ ErrTrailingComma = errors.New("extra delimiter at end of line") // Deprecated: No longer used.
+ ErrBareQuote = errors.New("bare \" in non-quoted-field")
+ ErrQuote = errors.New("extraneous or missing \" in quoted-field")
+ ErrFieldCount = errors.New("wrong number of fields")
+)
+
+var errInvalidDelim = errors.New("csv: invalid field or comment delimiter")
+
+func validDelim(r rune) bool {
+ return r != 0 && r != '"' && r != '\r' && r != '\n' && utf8.ValidRune(r) && r != utf8.RuneError
+}
+
+// A Reader reads records from a CSV-encoded file.
+//
+// As returned by NewReader, a Reader expects input conforming to RFC 4180.
+// The exported fields can be changed to customize the details before the
+// first call to Read or ReadAll.
+//
+// The Reader converts all \r\n sequences in its input to plain \n,
+// including in multiline field values, so that the returned data does
+// not depend on which line-ending convention an input file uses.
+type Reader struct {
+ // Comma is the field delimiter.
+ // It is set to comma (',') by NewReader.
+ // Comma must be a valid rune and must not be \r, \n,
+ // or the Unicode replacement character (0xFFFD).
+ Comma rune
+
+ // Comment, if not 0, is the comment character. Lines beginning with the
+ // Comment character without preceding whitespace are ignored.
+ // With leading whitespace the Comment character becomes part of the
+ // field, even if TrimLeadingSpace is true.
+ // Comment must be a valid rune and must not be \r, \n,
+ // or the Unicode replacement character (0xFFFD).
+ // It must also not be equal to Comma.
+ Comment rune
+
+ // FieldsPerRecord is the number of expected fields per record.
+ // If FieldsPerRecord is positive, Read requires each record to
+ // have the given number of fields. If FieldsPerRecord is 0, Read sets it to
+ // the number of fields in the first record, so that future records must
+ // have the same field count. If FieldsPerRecord is negative, no check is
+ // made and records may have a variable number of fields.
+ FieldsPerRecord int
+
+ // If LazyQuotes is true, a quote may appear in an unquoted field and a
+ // non-doubled quote may appear in a quoted field.
+ LazyQuotes bool
+
+ // If TrimLeadingSpace is true, leading white space in a field is ignored.
+ // This is done even if the field delimiter, Comma, is white space.
+ TrimLeadingSpace bool
+
+ // ReuseRecord controls whether calls to Read may return a slice sharing
+ // the backing array of the previous call's returned slice for performance.
+ // By default, each call to Read returns newly allocated memory owned by the caller.
+ ReuseRecord bool
+
+ TrailingComma bool // Deprecated: No longer used.
+
+ r *bufio.Reader
+
+ // numLine is the current line being read in the CSV file.
+ numLine int
+
+ // rawBuffer is a line buffer only used by the readLine method.
+ rawBuffer []byte
+
+ // recordBuffer holds the unescaped fields, one after another.
+ // The fields can be accessed by using the indexes in fieldIndexes.
+ // E.g., For the row `a,"b","c""d",e`, recordBuffer will contain `abc"de`
+ // and fieldIndexes will contain the indexes [1, 2, 5, 6].
+ recordBuffer []byte
+
+ // fieldIndexes is an index of fields inside recordBuffer.
+ // The i'th field ends at offset fieldIndexes[i] in recordBuffer.
+ fieldIndexes []int
+
+ // fieldPositions is an index of field positions for the
+ // last record returned by Read.
+ fieldPositions []position
+
+ // lastRecord is a record cache and only used when ReuseRecord == true.
+ lastRecord []string
+}
+
+// NewReader returns a new Reader that reads from r.
+func NewReader(r io.Reader) *Reader {
+ return &Reader{
+ Comma: ',',
+ r: bufio.NewReader(r),
+ }
+}
+
+// Read reads one record (a slice of fields) from r.
+// If the record has an unexpected number of fields,
+// Read returns the record along with the error ErrFieldCount.
+// Except for that case, Read always returns either a non-nil
+// record or a non-nil error, but not both.
+// If there is no data left to be read, Read returns nil, io.EOF.
+// If ReuseRecord is true, the returned slice may be shared
+// between multiple calls to Read.
+func (r *Reader) Read() (record []string, err error) {
+ if r.ReuseRecord {
+ record, err = r.readRecord(r.lastRecord)
+ r.lastRecord = record
+ } else {
+ record, err = r.readRecord(nil)
+ }
+ return record, err
+}
+
+// FieldPos returns the line and column corresponding to
+// the start of the field with the given index in the slice most recently
+// returned by Read. Numbering of lines and columns starts at 1;
+// columns are counted in bytes, not runes.
+//
+// If this is called with an out-of-bounds index, it panics.
+func (r *Reader) FieldPos(field int) (line, column int) {
+ if field < 0 || field >= len(r.fieldPositions) {
+ panic("out of range index passed to FieldPos")
+ }
+ p := &r.fieldPositions[field]
+ return p.line, p.col
+}
+
+// pos holds the position of a field in the current line.
+type position struct {
+ line, col int
+}
+
+// ReadAll reads all the remaining records from r.
+// Each record is a slice of fields.
+// A successful call returns err == nil, not err == io.EOF. Because ReadAll is
+// defined to read until EOF, it does not treat end of file as an error to be
+// reported.
+func (r *Reader) ReadAll() (records [][]string, err error) {
+ for {
+ record, err := r.readRecord(nil)
+ if err == io.EOF {
+ return records, nil
+ }
+ if err != nil {
+ return nil, err
+ }
+ records = append(records, record)
+ }
+}
+
+// readLine reads the next line (with the trailing endline).
+// If EOF is hit without a trailing endline, it will be omitted.
+// If some bytes were read, then the error is never io.EOF.
+// The result is only valid until the next call to readLine.
+func (r *Reader) readLine() ([]byte, error) {
+ line, err := r.r.ReadSlice('\n')
+ if err == bufio.ErrBufferFull {
+ r.rawBuffer = append(r.rawBuffer[:0], line...)
+ for err == bufio.ErrBufferFull {
+ line, err = r.r.ReadSlice('\n')
+ r.rawBuffer = append(r.rawBuffer, line...)
+ }
+ line = r.rawBuffer
+ }
+ if len(line) > 0 && err == io.EOF {
+ err = nil
+ // For backwards compatibility, drop trailing \r before EOF.
+ if line[len(line)-1] == '\r' {
+ line = line[:len(line)-1]
+ }
+ }
+ r.numLine++
+ // Normalize \r\n to \n on all input lines.
+ if n := len(line); n >= 2 && line[n-2] == '\r' && line[n-1] == '\n' {
+ line[n-2] = '\n'
+ line = line[:n-1]
+ }
+ return line, err
+}
+
+// lengthNL reports the number of bytes for the trailing \n.
+func lengthNL(b []byte) int {
+ if len(b) > 0 && b[len(b)-1] == '\n' {
+ return 1
+ }
+ return 0
+}
+
+// nextRune returns the next rune in b or utf8.RuneError.
+func nextRune(b []byte) rune {
+ r, _ := utf8.DecodeRune(b)
+ return r
+}
+
+func (r *Reader) readRecord(dst []string) ([]string, error) {
+ if r.Comma == r.Comment || !validDelim(r.Comma) || (r.Comment != 0 && !validDelim(r.Comment)) {
+ return nil, errInvalidDelim
+ }
+
+ // Read line (automatically skipping past empty lines and any comments).
+ var line []byte
+ var errRead error
+ for errRead == nil {
+ line, errRead = r.readLine()
+ if r.Comment != 0 && nextRune(line) == r.Comment {
+ line = nil
+ continue // Skip comment lines
+ }
+ if errRead == nil && len(line) == lengthNL(line) {
+ line = nil
+ continue // Skip empty lines
+ }
+ break
+ }
+ if errRead == io.EOF {
+ return nil, errRead
+ }
+
+ // Parse each field in the record.
+ var err error
+ const quoteLen = len(`"`)
+ commaLen := utf8.RuneLen(r.Comma)
+ recLine := r.numLine // Starting line for record
+ r.recordBuffer = r.recordBuffer[:0]
+ r.fieldIndexes = r.fieldIndexes[:0]
+ r.fieldPositions = r.fieldPositions[:0]
+ pos := position{line: r.numLine, col: 1}
+parseField:
+ for {
+ if r.TrimLeadingSpace {
+ i := bytes.IndexFunc(line, func(r rune) bool {
+ return !unicode.IsSpace(r)
+ })
+ if i < 0 {
+ i = len(line)
+ pos.col -= lengthNL(line)
+ }
+ line = line[i:]
+ pos.col += i
+ }
+ if len(line) == 0 || line[0] != '"' {
+ // Non-quoted string field
+ i := bytes.IndexRune(line, r.Comma)
+ field := line
+ if i >= 0 {
+ field = field[:i]
+ } else {
+ field = field[:len(field)-lengthNL(field)]
+ }
+ // Check to make sure a quote does not appear in field.
+ if !r.LazyQuotes {
+ if j := bytes.IndexByte(field, '"'); j >= 0 {
+ col := pos.col + j
+ err = &ParseError{StartLine: recLine, Line: r.numLine, Column: col, Err: ErrBareQuote}
+ break parseField
+ }
+ }
+ r.recordBuffer = append(r.recordBuffer, field...)
+ r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
+ r.fieldPositions = append(r.fieldPositions, pos)
+ if i >= 0 {
+ line = line[i+commaLen:]
+ pos.col += i + commaLen
+ continue parseField
+ }
+ break parseField
+ } else {
+ // Quoted string field
+ fieldPos := pos
+ line = line[quoteLen:]
+ pos.col += quoteLen
+ for {
+ i := bytes.IndexByte(line, '"')
+ if i >= 0 {
+ // Hit next quote.
+ r.recordBuffer = append(r.recordBuffer, line[:i]...)
+ line = line[i+quoteLen:]
+ pos.col += i + quoteLen
+ switch rn := nextRune(line); {
+ case rn == '"':
+ // `""` sequence (append quote).
+ r.recordBuffer = append(r.recordBuffer, '"')
+ line = line[quoteLen:]
+ pos.col += quoteLen
+ case rn == r.Comma:
+ // `",` sequence (end of field).
+ line = line[commaLen:]
+ pos.col += commaLen
+ r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
+ r.fieldPositions = append(r.fieldPositions, fieldPos)
+ continue parseField
+ case lengthNL(line) == len(line):
+ // `"\n` sequence (end of line).
+ r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
+ r.fieldPositions = append(r.fieldPositions, fieldPos)
+ break parseField
+ case r.LazyQuotes:
+ // `"` sequence (bare quote).
+ r.recordBuffer = append(r.recordBuffer, '"')
+ default:
+ // `"*` sequence (invalid non-escaped quote).
+ err = &ParseError{StartLine: recLine, Line: r.numLine, Column: pos.col - quoteLen, Err: ErrQuote}
+ break parseField
+ }
+ } else if len(line) > 0 {
+ // Hit end of line (copy all data so far).
+ r.recordBuffer = append(r.recordBuffer, line...)
+ if errRead != nil {
+ break parseField
+ }
+ pos.col += len(line)
+ line, errRead = r.readLine()
+ if len(line) > 0 {
+ pos.line++
+ pos.col = 1
+ }
+ if errRead == io.EOF {
+ errRead = nil
+ }
+ } else {
+ // Abrupt end of file (EOF or error).
+ if !r.LazyQuotes && errRead == nil {
+ err = &ParseError{StartLine: recLine, Line: pos.line, Column: pos.col, Err: ErrQuote}
+ break parseField
+ }
+ r.fieldIndexes = append(r.fieldIndexes, len(r.recordBuffer))
+ r.fieldPositions = append(r.fieldPositions, fieldPos)
+ break parseField
+ }
+ }
+ }
+ }
+ if err == nil {
+ err = errRead
+ }
+
+ // Create a single string and create slices out of it.
+ // This pins the memory of the fields together, but allocates once.
+ str := string(r.recordBuffer) // Convert to string once to batch allocations
+ dst = dst[:0]
+ if cap(dst) < len(r.fieldIndexes) {
+ dst = make([]string, len(r.fieldIndexes))
+ }
+ dst = dst[:len(r.fieldIndexes)]
+ var preIdx int
+ for i, idx := range r.fieldIndexes {
+ dst[i] = str[preIdx:idx]
+ preIdx = idx
+ }
+
+ // Check or update the expected fields per record.
+ if r.FieldsPerRecord > 0 {
+ if len(dst) != r.FieldsPerRecord && err == nil {
+ err = &ParseError{
+ StartLine: recLine,
+ Line: recLine,
+ Column: 1,
+ Err: ErrFieldCount,
+ }
+ }
+ } else if r.FieldsPerRecord == 0 {
+ r.FieldsPerRecord = len(dst)
+ }
+ return dst, err
+}
diff --git a/src/encoding/csv/reader_test.go b/src/encoding/csv/reader_test.go
new file mode 100644
index 0000000..abe3fdf
--- /dev/null
+++ b/src/encoding/csv/reader_test.go
@@ -0,0 +1,650 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package csv
+
+import (
+ "errors"
+ "fmt"
+ "io"
+ "reflect"
+ "strings"
+ "testing"
+ "unicode/utf8"
+)
+
+type readTest struct {
+ Name string
+ Input string
+ Output [][]string
+ Positions [][][2]int
+ Errors []error
+
+ // These fields are copied into the Reader
+ Comma rune
+ Comment rune
+ UseFieldsPerRecord bool // false (default) means FieldsPerRecord is -1
+ FieldsPerRecord int
+ LazyQuotes bool
+ TrimLeadingSpace bool
+ ReuseRecord bool
+}
+
+// In these tests, the §, ¶ and ∑ characters in readTest.Input are used to denote
+// the start of a field, a record boundary and the position of an error respectively.
+// They are removed before parsing and are used to verify the position
+// information reported by FieldPos.
+
+var readTests = []readTest{{
+ Name: "Simple",
+ Input: "§a,§b,§c\n",
+ Output: [][]string{{"a", "b", "c"}},
+}, {
+ Name: "CRLF",
+ Input: "§a,§b\r\n¶§c,§d\r\n",
+ Output: [][]string{{"a", "b"}, {"c", "d"}},
+}, {
+ Name: "BareCR",
+ Input: "§a,§b\rc,§d\r\n",
+ Output: [][]string{{"a", "b\rc", "d"}},
+}, {
+ Name: "RFC4180test",
+ Input: `§#field1,§field2,§field3
+¶§"aaa",§"bb
+b",§"ccc"
+¶§"a,a",§"b""bb",§"ccc"
+¶§zzz,§yyy,§xxx
+`,
+ Output: [][]string{
+ {"#field1", "field2", "field3"},
+ {"aaa", "bb\nb", "ccc"},
+ {"a,a", `b"bb`, "ccc"},
+ {"zzz", "yyy", "xxx"},
+ },
+ UseFieldsPerRecord: true,
+ FieldsPerRecord: 0,
+}, {
+ Name: "NoEOLTest",
+ Input: "§a,§b,§c",
+ Output: [][]string{{"a", "b", "c"}},
+}, {
+ Name: "Semicolon",
+ Input: "§a;§b;§c\n",
+ Output: [][]string{{"a", "b", "c"}},
+ Comma: ';',
+}, {
+ Name: "MultiLine",
+ Input: `§"two
+line",§"one line",§"three
+line
+field"`,
+ Output: [][]string{{"two\nline", "one line", "three\nline\nfield"}},
+}, {
+ Name: "BlankLine",
+ Input: "§a,§b,§c\n\n¶§d,§e,§f\n\n",
+ Output: [][]string{
+ {"a", "b", "c"},
+ {"d", "e", "f"},
+ },
+}, {
+ Name: "BlankLineFieldCount",
+ Input: "§a,§b,§c\n\n¶§d,§e,§f\n\n",
+ Output: [][]string{
+ {"a", "b", "c"},
+ {"d", "e", "f"},
+ },
+ UseFieldsPerRecord: true,
+ FieldsPerRecord: 0,
+}, {
+ Name: "TrimSpace",
+ Input: " §a, §b, §c\n",
+ Output: [][]string{{"a", "b", "c"}},
+ TrimLeadingSpace: true,
+}, {
+ Name: "LeadingSpace",
+ Input: "§ a,§ b,§ c\n",
+ Output: [][]string{{" a", " b", " c"}},
+}, {
+ Name: "Comment",
+ Input: "#1,2,3\n§a,§b,§c\n#comment",
+ Output: [][]string{{"a", "b", "c"}},
+ Comment: '#',
+}, {
+ Name: "NoComment",
+ Input: "§#1,§2,§3\n¶§a,§b,§c",
+ Output: [][]string{{"#1", "2", "3"}, {"a", "b", "c"}},
+}, {
+ Name: "LazyQuotes",
+ Input: `§a "word",§"1"2",§a",§"b`,
+ Output: [][]string{{`a "word"`, `1"2`, `a"`, `b`}},
+ LazyQuotes: true,
+}, {
+ Name: "BareQuotes",
+ Input: `§a "word",§"1"2",§a"`,
+ Output: [][]string{{`a "word"`, `1"2`, `a"`}},
+ LazyQuotes: true,
+}, {
+ Name: "BareDoubleQuotes",
+ Input: `§a""b,§c`,
+ Output: [][]string{{`a""b`, `c`}},
+ LazyQuotes: true,
+}, {
+ Name: "BadDoubleQuotes",
+ Input: `§a∑""b,c`,
+ Errors: []error{&ParseError{Err: ErrBareQuote}},
+}, {
+ Name: "TrimQuote",
+ Input: ` §"a",§" b",§c`,
+ Output: [][]string{{"a", " b", "c"}},
+ TrimLeadingSpace: true,
+}, {
+ Name: "BadBareQuote",
+ Input: `§a ∑"word","b"`,
+ Errors: []error{&ParseError{Err: ErrBareQuote}},
+}, {
+ Name: "BadTrailingQuote",
+ Input: `§"a word",b∑"`,
+ Errors: []error{&ParseError{Err: ErrBareQuote}},
+}, {
+ Name: "ExtraneousQuote",
+ Input: `§"a ∑"word","b"`,
+ Errors: []error{&ParseError{Err: ErrQuote}},
+}, {
+ Name: "BadFieldCount",
+ Input: "§a,§b,§c\n¶∑§d,§e",
+ Errors: []error{nil, &ParseError{Err: ErrFieldCount}},
+ Output: [][]string{{"a", "b", "c"}, {"d", "e"}},
+ UseFieldsPerRecord: true,
+ FieldsPerRecord: 0,
+}, {
+ Name: "BadFieldCountMultiple",
+ Input: "§a,§b,§c\n¶∑§d,§e\n¶∑§f",
+ Errors: []error{nil, &ParseError{Err: ErrFieldCount}, &ParseError{Err: ErrFieldCount}},
+ Output: [][]string{{"a", "b", "c"}, {"d", "e"}, {"f"}},
+ UseFieldsPerRecord: true,
+ FieldsPerRecord: 0,
+}, {
+ Name: "BadFieldCount1",
+ Input: `§∑a,§b,§c`,
+ Errors: []error{&ParseError{Err: ErrFieldCount}},
+ Output: [][]string{{"a", "b", "c"}},
+ UseFieldsPerRecord: true,
+ FieldsPerRecord: 2,
+}, {
+ Name: "FieldCount",
+ Input: "§a,§b,§c\n¶§d,§e",
+ Output: [][]string{{"a", "b", "c"}, {"d", "e"}},
+}, {
+ Name: "TrailingCommaEOF",
+ Input: "§a,§b,§c,§",
+ Output: [][]string{{"a", "b", "c", ""}},
+}, {
+ Name: "TrailingCommaEOL",
+ Input: "§a,§b,§c,§\n",
+ Output: [][]string{{"a", "b", "c", ""}},
+}, {
+ Name: "TrailingCommaSpaceEOF",
+ Input: "§a,§b,§c, §",
+ Output: [][]string{{"a", "b", "c", ""}},
+ TrimLeadingSpace: true,
+}, {
+ Name: "TrailingCommaSpaceEOL",
+ Input: "§a,§b,§c, §\n",
+ Output: [][]string{{"a", "b", "c", ""}},
+ TrimLeadingSpace: true,
+}, {
+ Name: "TrailingCommaLine3",
+ Input: "§a,§b,§c\n¶§d,§e,§f\n¶§g,§hi,§",
+ Output: [][]string{{"a", "b", "c"}, {"d", "e", "f"}, {"g", "hi", ""}},
+ TrimLeadingSpace: true,
+}, {
+ Name: "NotTrailingComma3",
+ Input: "§a,§b,§c,§ \n",
+ Output: [][]string{{"a", "b", "c", " "}},
+}, {
+ Name: "CommaFieldTest",
+ Input: `§x,§y,§z,§w
+¶§x,§y,§z,§
+¶§x,§y,§,§
+¶§x,§,§,§
+¶§,§,§,§
+¶§"x",§"y",§"z",§"w"
+¶§"x",§"y",§"z",§""
+¶§"x",§"y",§"",§""
+¶§"x",§"",§"",§""
+¶§"",§"",§"",§""
+`,
+ Output: [][]string{
+ {"x", "y", "z", "w"},
+ {"x", "y", "z", ""},
+ {"x", "y", "", ""},
+ {"x", "", "", ""},
+ {"", "", "", ""},
+ {"x", "y", "z", "w"},
+ {"x", "y", "z", ""},
+ {"x", "y", "", ""},
+ {"x", "", "", ""},
+ {"", "", "", ""},
+ },
+}, {
+ Name: "TrailingCommaIneffective1",
+ Input: "§a,§b,§\n¶§c,§d,§e",
+ Output: [][]string{
+ {"a", "b", ""},
+ {"c", "d", "e"},
+ },
+ TrimLeadingSpace: true,
+}, {
+ Name: "ReadAllReuseRecord",
+ Input: "§a,§b\n¶§c,§d",
+ Output: [][]string{
+ {"a", "b"},
+ {"c", "d"},
+ },
+ ReuseRecord: true,
+}, {
+ Name: "StartLine1", // Issue 19019
+ Input: "§a,\"b\nc∑\"d,e",
+ Errors: []error{&ParseError{Err: ErrQuote}},
+}, {
+ Name: "StartLine2",
+ Input: "§a,§b\n¶§\"d\n\n,e∑",
+ Errors: []error{nil, &ParseError{Err: ErrQuote}},
+ Output: [][]string{{"a", "b"}},
+}, {
+ Name: "CRLFInQuotedField", // Issue 21201
+ Input: "§A,§\"Hello\r\nHi\",§B\r\n",
+ Output: [][]string{
+ {"A", "Hello\nHi", "B"},
+ },
+}, {
+ Name: "BinaryBlobField", // Issue 19410
+ Input: "§x09\x41\xb4\x1c,§aktau",
+ Output: [][]string{{"x09A\xb4\x1c", "aktau"}},
+}, {
+ Name: "TrailingCR",
+ Input: "§field1,§field2\r",
+ Output: [][]string{{"field1", "field2"}},
+}, {
+ Name: "QuotedTrailingCR",
+ Input: "§\"field\"\r",
+ Output: [][]string{{"field"}},
+}, {
+ Name: "QuotedTrailingCRCR",
+ Input: "§\"field∑\"\r\r",
+ Errors: []error{&ParseError{Err: ErrQuote}},
+}, {
+ Name: "FieldCR",
+ Input: "§field\rfield\r",
+ Output: [][]string{{"field\rfield"}},
+}, {
+ Name: "FieldCRCR",
+ Input: "§field\r\rfield\r\r",
+ Output: [][]string{{"field\r\rfield\r"}},
+}, {
+ Name: "FieldCRCRLF",
+ Input: "§field\r\r\n¶§field\r\r\n",
+ Output: [][]string{{"field\r"}, {"field\r"}},
+}, {
+ Name: "FieldCRCRLFCR",
+ Input: "§field\r\r\n¶§\rfield\r\r\n\r",
+ Output: [][]string{{"field\r"}, {"\rfield\r"}},
+}, {
+ Name: "FieldCRCRLFCRCR",
+ Input: "§field\r\r\n¶§\r\rfield\r\r\n¶§\r\r",
+ Output: [][]string{{"field\r"}, {"\r\rfield\r"}, {"\r"}},
+}, {
+ Name: "MultiFieldCRCRLFCRCR",
+ Input: "§field1,§field2\r\r\n¶§\r\rfield1,§field2\r\r\n¶§\r\r,§",
+ Output: [][]string{
+ {"field1", "field2\r"},
+ {"\r\rfield1", "field2\r"},
+ {"\r\r", ""},
+ },
+}, {
+ Name: "NonASCIICommaAndComment",
+ Input: "§a£§b,c£ \t§d,e\n€ comment\n",
+ Output: [][]string{{"a", "b,c", "d,e"}},
+ TrimLeadingSpace: true,
+ Comma: '£',
+ Comment: '€',
+}, {
+ Name: "NonASCIICommaAndCommentWithQuotes",
+ Input: "§a€§\" b,\"€§ c\nλ comment\n",
+ Output: [][]string{{"a", " b,", " c"}},
+ Comma: '€',
+ Comment: 'λ',
+}, {
+ // λ and θ start with the same byte.
+ // This tests that the parser doesn't confuse such characters.
+ Name: "NonASCIICommaConfusion",
+ Input: "§\"abθcd\"λ§efθgh",
+ Output: [][]string{{"abθcd", "efθgh"}},
+ Comma: 'λ',
+ Comment: '€',
+}, {
+ Name: "NonASCIICommentConfusion",
+ Input: "§λ\n¶§λ\nθ\n¶§λ\n",
+ Output: [][]string{{"λ"}, {"λ"}, {"λ"}},
+ Comment: 'θ',
+}, {
+ Name: "QuotedFieldMultipleLF",
+ Input: "§\"\n\n\n\n\"",
+ Output: [][]string{{"\n\n\n\n"}},
+}, {
+ Name: "MultipleCRLF",
+ Input: "\r\n\r\n\r\n\r\n",
+}, {
+ // The implementation may read each line in several chunks if it doesn't fit entirely
+ // in the read buffer, so we should test the code to handle that condition.
+ Name: "HugeLines",
+ Input: strings.Repeat("#ignore\n", 10000) + "§" + strings.Repeat("@", 5000) + ",§" + strings.Repeat("*", 5000),
+ Output: [][]string{{strings.Repeat("@", 5000), strings.Repeat("*", 5000)}},
+ Comment: '#',
+}, {
+ Name: "QuoteWithTrailingCRLF",
+ Input: "§\"foo∑\"bar\"\r\n",
+ Errors: []error{&ParseError{Err: ErrQuote}},
+}, {
+ Name: "LazyQuoteWithTrailingCRLF",
+ Input: "§\"foo\"bar\"\r\n",
+ Output: [][]string{{`foo"bar`}},
+ LazyQuotes: true,
+}, {
+ Name: "DoubleQuoteWithTrailingCRLF",
+ Input: "§\"foo\"\"bar\"\r\n",
+ Output: [][]string{{`foo"bar`}},
+}, {
+ Name: "EvenQuotes",
+ Input: `§""""""""`,
+ Output: [][]string{{`"""`}},
+}, {
+ Name: "OddQuotes",
+ Input: `§"""""""∑`,
+ Errors: []error{&ParseError{Err: ErrQuote}},
+}, {
+ Name: "LazyOddQuotes",
+ Input: `§"""""""`,
+ Output: [][]string{{`"""`}},
+ LazyQuotes: true,
+}, {
+ Name: "BadComma1",
+ Comma: '\n',
+ Errors: []error{errInvalidDelim},
+}, {
+ Name: "BadComma2",
+ Comma: '\r',
+ Errors: []error{errInvalidDelim},
+}, {
+ Name: "BadComma3",
+ Comma: '"',
+ Errors: []error{errInvalidDelim},
+}, {
+ Name: "BadComma4",
+ Comma: utf8.RuneError,
+ Errors: []error{errInvalidDelim},
+}, {
+ Name: "BadComment1",
+ Comment: '\n',
+ Errors: []error{errInvalidDelim},
+}, {
+ Name: "BadComment2",
+ Comment: '\r',
+ Errors: []error{errInvalidDelim},
+}, {
+ Name: "BadComment3",
+ Comment: utf8.RuneError,
+ Errors: []error{errInvalidDelim},
+}, {
+ Name: "BadCommaComment",
+ Comma: 'X',
+ Comment: 'X',
+ Errors: []error{errInvalidDelim},
+}}
+
+func TestRead(t *testing.T) {
+ newReader := func(tt readTest) (*Reader, [][][2]int, map[int][2]int) {
+ positions, errPositions, input := makePositions(tt.Input)
+ r := NewReader(strings.NewReader(input))
+
+ if tt.Comma != 0 {
+ r.Comma = tt.Comma
+ }
+ r.Comment = tt.Comment
+ if tt.UseFieldsPerRecord {
+ r.FieldsPerRecord = tt.FieldsPerRecord
+ } else {
+ r.FieldsPerRecord = -1
+ }
+ r.LazyQuotes = tt.LazyQuotes
+ r.TrimLeadingSpace = tt.TrimLeadingSpace
+ r.ReuseRecord = tt.ReuseRecord
+ return r, positions, errPositions
+ }
+
+ for _, tt := range readTests {
+ t.Run(tt.Name, func(t *testing.T) {
+ r, positions, errPositions := newReader(tt)
+ out, err := r.ReadAll()
+ if wantErr := firstError(tt.Errors, positions, errPositions); wantErr != nil {
+ if !reflect.DeepEqual(err, wantErr) {
+ t.Fatalf("ReadAll() error mismatch:\ngot %v (%#v)\nwant %v (%#v)", err, err, wantErr, wantErr)
+ }
+ if out != nil {
+ t.Fatalf("ReadAll() output:\ngot %q\nwant nil", out)
+ }
+ } else {
+ if err != nil {
+ t.Fatalf("unexpected Readall() error: %v", err)
+ }
+ if !reflect.DeepEqual(out, tt.Output) {
+ t.Fatalf("ReadAll() output:\ngot %q\nwant %q", out, tt.Output)
+ }
+ }
+
+ // Check field and error positions.
+ r, _, _ = newReader(tt)
+ for recNum := 0; ; recNum++ {
+ rec, err := r.Read()
+ var wantErr error
+ if recNum < len(tt.Errors) && tt.Errors[recNum] != nil {
+ wantErr = errorWithPosition(tt.Errors[recNum], recNum, positions, errPositions)
+ } else if recNum >= len(tt.Output) {
+ wantErr = io.EOF
+ }
+ if !reflect.DeepEqual(err, wantErr) {
+ t.Fatalf("Read() error at record %d:\ngot %v (%#v)\nwant %v (%#v)", recNum, err, err, wantErr, wantErr)
+ }
+ // ErrFieldCount is explicitly non-fatal.
+ if err != nil && !errors.Is(err, ErrFieldCount) {
+ if recNum < len(tt.Output) {
+ t.Fatalf("need more records; got %d want %d", recNum, len(tt.Output))
+ }
+ break
+ }
+ if got, want := rec, tt.Output[recNum]; !reflect.DeepEqual(got, want) {
+ t.Errorf("Read vs ReadAll mismatch;\ngot %q\nwant %q", got, want)
+ }
+ pos := positions[recNum]
+ if len(pos) != len(rec) {
+ t.Fatalf("mismatched position length at record %d", recNum)
+ }
+ for i := range rec {
+ line, col := r.FieldPos(i)
+ if got, want := [2]int{line, col}, pos[i]; got != want {
+ t.Errorf("position mismatch at record %d, field %d;\ngot %v\nwant %v", recNum, i, got, want)
+ }
+ }
+ }
+ })
+ }
+}
+
+// firstError returns the first non-nil error in errs,
+// with the position adjusted according to the error's
+// index inside positions.
+func firstError(errs []error, positions [][][2]int, errPositions map[int][2]int) error {
+ for i, err := range errs {
+ if err != nil {
+ return errorWithPosition(err, i, positions, errPositions)
+ }
+ }
+ return nil
+}
+
+func errorWithPosition(err error, recNum int, positions [][][2]int, errPositions map[int][2]int) error {
+ parseErr, ok := err.(*ParseError)
+ if !ok {
+ return err
+ }
+ if recNum >= len(positions) {
+ panic(fmt.Errorf("no positions found for error at record %d", recNum))
+ }
+ errPos, ok := errPositions[recNum]
+ if !ok {
+ panic(fmt.Errorf("no error position found for error at record %d", recNum))
+ }
+ parseErr1 := *parseErr
+ parseErr1.StartLine = positions[recNum][0][0]
+ parseErr1.Line = errPos[0]
+ parseErr1.Column = errPos[1]
+ return &parseErr1
+}
+
+// makePositions returns the expected field positions of all
+// the fields in text, the positions of any errors, and the text with the position markers
+// removed.
+//
+// The start of each field is marked with a § symbol;
+// CSV lines are separated by ¶ symbols;
+// Error positions are marked with ∑ symbols.
+func makePositions(text string) ([][][2]int, map[int][2]int, string) {
+ buf := make([]byte, 0, len(text))
+ var positions [][][2]int
+ errPositions := make(map[int][2]int)
+ line, col := 1, 1
+ recNum := 0
+
+ for len(text) > 0 {
+ r, size := utf8.DecodeRuneInString(text)
+ switch r {
+ case '\n':
+ line++
+ col = 1
+ buf = append(buf, '\n')
+ case '§':
+ if len(positions) == 0 {
+ positions = append(positions, [][2]int{})
+ }
+ positions[len(positions)-1] = append(positions[len(positions)-1], [2]int{line, col})
+ case '¶':
+ positions = append(positions, [][2]int{})
+ recNum++
+ case '∑':
+ errPositions[recNum] = [2]int{line, col}
+ default:
+ buf = append(buf, text[:size]...)
+ col += size
+ }
+ text = text[size:]
+ }
+ return positions, errPositions, string(buf)
+}
+
+// nTimes is an io.Reader which yields the string s n times.
+type nTimes struct {
+ s string
+ n int
+ off int
+}
+
+func (r *nTimes) Read(p []byte) (n int, err error) {
+ for {
+ if r.n <= 0 || r.s == "" {
+ return n, io.EOF
+ }
+ n0 := copy(p, r.s[r.off:])
+ p = p[n0:]
+ n += n0
+ r.off += n0
+ if r.off == len(r.s) {
+ r.off = 0
+ r.n--
+ }
+ if len(p) == 0 {
+ return
+ }
+ }
+}
+
+// benchmarkRead measures reading the provided CSV rows data.
+// initReader, if non-nil, modifies the Reader before it's used.
+func benchmarkRead(b *testing.B, initReader func(*Reader), rows string) {
+ b.ReportAllocs()
+ r := NewReader(&nTimes{s: rows, n: b.N})
+ if initReader != nil {
+ initReader(r)
+ }
+ for {
+ _, err := r.Read()
+ if err == io.EOF {
+ break
+ }
+ if err != nil {
+ b.Fatal(err)
+ }
+ }
+}
+
+const benchmarkCSVData = `x,y,z,w
+x,y,z,
+x,y,,
+x,,,
+,,,
+"x","y","z","w"
+"x","y","z",""
+"x","y","",""
+"x","","",""
+"","","",""
+`
+
+func BenchmarkRead(b *testing.B) {
+ benchmarkRead(b, nil, benchmarkCSVData)
+}
+
+func BenchmarkReadWithFieldsPerRecord(b *testing.B) {
+ benchmarkRead(b, func(r *Reader) { r.FieldsPerRecord = 4 }, benchmarkCSVData)
+}
+
+func BenchmarkReadWithoutFieldsPerRecord(b *testing.B) {
+ benchmarkRead(b, func(r *Reader) { r.FieldsPerRecord = -1 }, benchmarkCSVData)
+}
+
+func BenchmarkReadLargeFields(b *testing.B) {
+ benchmarkRead(b, nil, strings.Repeat(`xxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+xxxxxxxxxxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvv
+,,zzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+`, 3))
+}
+
+func BenchmarkReadReuseRecord(b *testing.B) {
+ benchmarkRead(b, func(r *Reader) { r.ReuseRecord = true }, benchmarkCSVData)
+}
+
+func BenchmarkReadReuseRecordWithFieldsPerRecord(b *testing.B) {
+ benchmarkRead(b, func(r *Reader) { r.ReuseRecord = true; r.FieldsPerRecord = 4 }, benchmarkCSVData)
+}
+
+func BenchmarkReadReuseRecordWithoutFieldsPerRecord(b *testing.B) {
+ benchmarkRead(b, func(r *Reader) { r.ReuseRecord = true; r.FieldsPerRecord = -1 }, benchmarkCSVData)
+}
+
+func BenchmarkReadReuseRecordLargeFields(b *testing.B) {
+ benchmarkRead(b, func(r *Reader) { r.ReuseRecord = true }, strings.Repeat(`xxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+xxxxxxxxxxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvv
+,,zzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx,yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz,wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww,vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+`, 3))
+}
diff --git a/src/encoding/csv/writer.go b/src/encoding/csv/writer.go
new file mode 100644
index 0000000..ac64b4d
--- /dev/null
+++ b/src/encoding/csv/writer.go
@@ -0,0 +1,181 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package csv
+
+import (
+ "bufio"
+ "io"
+ "strings"
+ "unicode"
+ "unicode/utf8"
+)
+
+// A Writer writes records using CSV encoding.
+//
+// As returned by NewWriter, a Writer writes records terminated by a
+// newline and uses ',' as the field delimiter. The exported fields can be
+// changed to customize the details before the first call to Write or WriteAll.
+//
+// Comma is the field delimiter.
+//
+// If UseCRLF is true, the Writer ends each output line with \r\n instead of \n.
+//
+// The writes of individual records are buffered.
+// After all data has been written, the client should call the
+// Flush method to guarantee all data has been forwarded to
+// the underlying io.Writer. Any errors that occurred should
+// be checked by calling the Error method.
+type Writer struct {
+ Comma rune // Field delimiter (set to ',' by NewWriter)
+ UseCRLF bool // True to use \r\n as the line terminator
+ w *bufio.Writer
+}
+
+// NewWriter returns a new Writer that writes to w.
+func NewWriter(w io.Writer) *Writer {
+ return &Writer{
+ Comma: ',',
+ w: bufio.NewWriter(w),
+ }
+}
+
+// Write writes a single CSV record to w along with any necessary quoting.
+// A record is a slice of strings with each string being one field.
+// Writes are buffered, so Flush must eventually be called to ensure
+// that the record is written to the underlying io.Writer.
+func (w *Writer) Write(record []string) error {
+ if !validDelim(w.Comma) {
+ return errInvalidDelim
+ }
+
+ for n, field := range record {
+ if n > 0 {
+ if _, err := w.w.WriteRune(w.Comma); err != nil {
+ return err
+ }
+ }
+
+ // If we don't have to have a quoted field then just
+ // write out the field and continue to the next field.
+ if !w.fieldNeedsQuotes(field) {
+ if _, err := w.w.WriteString(field); err != nil {
+ return err
+ }
+ continue
+ }
+
+ if err := w.w.WriteByte('"'); err != nil {
+ return err
+ }
+ for len(field) > 0 {
+ // Search for special characters.
+ i := strings.IndexAny(field, "\"\r\n")
+ if i < 0 {
+ i = len(field)
+ }
+
+ // Copy verbatim everything before the special character.
+ if _, err := w.w.WriteString(field[:i]); err != nil {
+ return err
+ }
+ field = field[i:]
+
+ // Encode the special character.
+ if len(field) > 0 {
+ var err error
+ switch field[0] {
+ case '"':
+ _, err = w.w.WriteString(`""`)
+ case '\r':
+ if !w.UseCRLF {
+ err = w.w.WriteByte('\r')
+ }
+ case '\n':
+ if w.UseCRLF {
+ _, err = w.w.WriteString("\r\n")
+ } else {
+ err = w.w.WriteByte('\n')
+ }
+ }
+ field = field[1:]
+ if err != nil {
+ return err
+ }
+ }
+ }
+ if err := w.w.WriteByte('"'); err != nil {
+ return err
+ }
+ }
+ var err error
+ if w.UseCRLF {
+ _, err = w.w.WriteString("\r\n")
+ } else {
+ err = w.w.WriteByte('\n')
+ }
+ return err
+}
+
+// Flush writes any buffered data to the underlying io.Writer.
+// To check if an error occurred during the Flush, call Error.
+func (w *Writer) Flush() {
+ w.w.Flush()
+}
+
+// Error reports any error that has occurred during a previous Write or Flush.
+func (w *Writer) Error() error {
+ _, err := w.w.Write(nil)
+ return err
+}
+
+// WriteAll writes multiple CSV records to w using Write and then calls Flush,
+// returning any error from the Flush.
+func (w *Writer) WriteAll(records [][]string) error {
+ for _, record := range records {
+ err := w.Write(record)
+ if err != nil {
+ return err
+ }
+ }
+ return w.w.Flush()
+}
+
+// fieldNeedsQuotes reports whether our field must be enclosed in quotes.
+// Fields with a Comma, fields with a quote or newline, and
+// fields which start with a space must be enclosed in quotes.
+// We used to quote empty strings, but we do not anymore (as of Go 1.4).
+// The two representations should be equivalent, but Postgres distinguishes
+// quoted vs non-quoted empty string during database imports, and it has
+// an option to force the quoted behavior for non-quoted CSV but it has
+// no option to force the non-quoted behavior for quoted CSV, making
+// CSV with quoted empty strings strictly less useful.
+// Not quoting the empty string also makes this package match the behavior
+// of Microsoft Excel and Google Drive.
+// For Postgres, quote the data terminating string `\.`.
+func (w *Writer) fieldNeedsQuotes(field string) bool {
+ if field == "" {
+ return false
+ }
+
+ if field == `\.` {
+ return true
+ }
+
+ if w.Comma < utf8.RuneSelf {
+ for i := 0; i < len(field); i++ {
+ c := field[i]
+ if c == '\n' || c == '\r' || c == '"' || c == byte(w.Comma) {
+ return true
+ }
+ }
+ } else {
+ if strings.ContainsRune(field, w.Comma) || strings.ContainsAny(field, "\"\r\n") {
+ return true
+ }
+ }
+
+ r1, _ := utf8.DecodeRuneInString(field)
+ return unicode.IsSpace(r1)
+}
diff --git a/src/encoding/csv/writer_test.go b/src/encoding/csv/writer_test.go
new file mode 100644
index 0000000..ab28b0d
--- /dev/null
+++ b/src/encoding/csv/writer_test.go
@@ -0,0 +1,112 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package csv
+
+import (
+ "bytes"
+ "errors"
+ "testing"
+)
+
+var writeTests = []struct {
+ Input [][]string
+ Output string
+ Error error
+ UseCRLF bool
+ Comma rune
+}{
+ {Input: [][]string{{"abc"}}, Output: "abc\n"},
+ {Input: [][]string{{"abc"}}, Output: "abc\r\n", UseCRLF: true},
+ {Input: [][]string{{`"abc"`}}, Output: `"""abc"""` + "\n"},
+ {Input: [][]string{{`a"b`}}, Output: `"a""b"` + "\n"},
+ {Input: [][]string{{`"a"b"`}}, Output: `"""a""b"""` + "\n"},
+ {Input: [][]string{{" abc"}}, Output: `" abc"` + "\n"},
+ {Input: [][]string{{"abc,def"}}, Output: `"abc,def"` + "\n"},
+ {Input: [][]string{{"abc", "def"}}, Output: "abc,def\n"},
+ {Input: [][]string{{"abc"}, {"def"}}, Output: "abc\ndef\n"},
+ {Input: [][]string{{"abc\ndef"}}, Output: "\"abc\ndef\"\n"},
+ {Input: [][]string{{"abc\ndef"}}, Output: "\"abc\r\ndef\"\r\n", UseCRLF: true},
+ {Input: [][]string{{"abc\rdef"}}, Output: "\"abcdef\"\r\n", UseCRLF: true},
+ {Input: [][]string{{"abc\rdef"}}, Output: "\"abc\rdef\"\n", UseCRLF: false},
+ {Input: [][]string{{""}}, Output: "\n"},
+ {Input: [][]string{{"", ""}}, Output: ",\n"},
+ {Input: [][]string{{"", "", ""}}, Output: ",,\n"},
+ {Input: [][]string{{"", "", "a"}}, Output: ",,a\n"},
+ {Input: [][]string{{"", "a", ""}}, Output: ",a,\n"},
+ {Input: [][]string{{"", "a", "a"}}, Output: ",a,a\n"},
+ {Input: [][]string{{"a", "", ""}}, Output: "a,,\n"},
+ {Input: [][]string{{"a", "", "a"}}, Output: "a,,a\n"},
+ {Input: [][]string{{"a", "a", ""}}, Output: "a,a,\n"},
+ {Input: [][]string{{"a", "a", "a"}}, Output: "a,a,a\n"},
+ {Input: [][]string{{`\.`}}, Output: "\"\\.\"\n"},
+ {Input: [][]string{{"x09\x41\xb4\x1c", "aktau"}}, Output: "x09\x41\xb4\x1c,aktau\n"},
+ {Input: [][]string{{",x09\x41\xb4\x1c", "aktau"}}, Output: "\",x09\x41\xb4\x1c\",aktau\n"},
+ {Input: [][]string{{"a", "a", ""}}, Output: "a|a|\n", Comma: '|'},
+ {Input: [][]string{{",", ",", ""}}, Output: ",|,|\n", Comma: '|'},
+ {Input: [][]string{{"foo"}}, Comma: '"', Error: errInvalidDelim},
+}
+
+func TestWrite(t *testing.T) {
+ for n, tt := range writeTests {
+ b := &bytes.Buffer{}
+ f := NewWriter(b)
+ f.UseCRLF = tt.UseCRLF
+ if tt.Comma != 0 {
+ f.Comma = tt.Comma
+ }
+ err := f.WriteAll(tt.Input)
+ if err != tt.Error {
+ t.Errorf("Unexpected error:\ngot %v\nwant %v", err, tt.Error)
+ }
+ out := b.String()
+ if out != tt.Output {
+ t.Errorf("#%d: out=%q want %q", n, out, tt.Output)
+ }
+ }
+}
+
+type errorWriter struct{}
+
+func (e errorWriter) Write(b []byte) (int, error) {
+ return 0, errors.New("Test")
+}
+
+func TestError(t *testing.T) {
+ b := &bytes.Buffer{}
+ f := NewWriter(b)
+ f.Write([]string{"abc"})
+ f.Flush()
+ err := f.Error()
+
+ if err != nil {
+ t.Errorf("Unexpected error: %s\n", err)
+ }
+
+ f = NewWriter(errorWriter{})
+ f.Write([]string{"abc"})
+ f.Flush()
+ err = f.Error()
+
+ if err == nil {
+ t.Error("Error should not be nil")
+ }
+}
+
+var benchmarkWriteData = [][]string{
+ {"abc", "def", "12356", "1234567890987654311234432141542132"},
+ {"abc", "def", "12356", "1234567890987654311234432141542132"},
+ {"abc", "def", "12356", "1234567890987654311234432141542132"},
+}
+
+func BenchmarkWrite(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ w := NewWriter(&bytes.Buffer{})
+ err := w.WriteAll(benchmarkWriteData)
+ if err != nil {
+ b.Fatal(err)
+ }
+ w.Flush()
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-19 17:12:14 +0000