mirror of
https://github.com/go-gitea/gitea
synced 2024-12-15 22:44:06 +01:00
fc039167d2
To make sure Gitea's next release's lifecycle could have active Golang support. And min/max are builtin now.
469 lines
13 KiB
Go
469 lines
13 KiB
Go
// Copyright 2021 The Gitea Authors. All rights reserved.
|
|
// SPDX-License-Identifier: MIT
|
|
|
|
package gitdiff
|
|
|
|
import (
|
|
"encoding/csv"
|
|
"errors"
|
|
"io"
|
|
)
|
|
|
|
const (
|
|
unmappedColumn = -1
|
|
maxRowsToInspect int = 10
|
|
minRatioToMatch float32 = 0.8
|
|
)
|
|
|
|
// TableDiffCellType represents the type of a TableDiffCell.
|
|
type TableDiffCellType uint8
|
|
|
|
// TableDiffCellType possible values.
|
|
const (
|
|
TableDiffCellUnchanged TableDiffCellType = iota + 1
|
|
TableDiffCellChanged
|
|
TableDiffCellAdd
|
|
TableDiffCellDel
|
|
TableDiffCellMovedUnchanged
|
|
TableDiffCellMovedChanged
|
|
)
|
|
|
|
// TableDiffCell represents a cell of a TableDiffRow
|
|
type TableDiffCell struct {
|
|
LeftCell string
|
|
RightCell string
|
|
Type TableDiffCellType
|
|
}
|
|
|
|
// TableDiffRow represents a row of a TableDiffSection.
|
|
type TableDiffRow struct {
|
|
RowIdx int
|
|
Cells []*TableDiffCell
|
|
}
|
|
|
|
// TableDiffSection represents a section of a DiffFile.
|
|
type TableDiffSection struct {
|
|
Rows []*TableDiffRow
|
|
}
|
|
|
|
// csvReader wraps a csv.Reader which buffers the first rows.
|
|
type csvReader struct {
|
|
reader *csv.Reader
|
|
buffer [][]string
|
|
line int
|
|
eof bool
|
|
}
|
|
|
|
// ErrorUndefinedCell is for when a row, column coordinates do not exist in the CSV
|
|
var ErrorUndefinedCell = errors.New("undefined cell")
|
|
|
|
// createCsvReader creates a csvReader and fills the buffer
|
|
func createCsvReader(reader *csv.Reader, bufferRowCount int) (*csvReader, error) {
|
|
csv := &csvReader{reader: reader}
|
|
csv.buffer = make([][]string, bufferRowCount)
|
|
for i := 0; i < bufferRowCount && !csv.eof; i++ {
|
|
row, err := csv.readNextRow()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
csv.buffer[i] = row
|
|
}
|
|
csv.line = bufferRowCount
|
|
return csv, nil
|
|
}
|
|
|
|
// GetRow gets a row from the buffer if present or advances the reader to the requested row. On the end of the file only nil gets returned.
|
|
func (csv *csvReader) GetRow(row int) ([]string, error) {
|
|
if row < len(csv.buffer) && row >= 0 {
|
|
return csv.buffer[row], nil
|
|
}
|
|
if csv.eof {
|
|
return nil, nil
|
|
}
|
|
for {
|
|
fields, err := csv.readNextRow()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if csv.eof {
|
|
return nil, nil
|
|
}
|
|
csv.line++
|
|
if csv.line-1 == row {
|
|
return fields, nil
|
|
}
|
|
}
|
|
}
|
|
|
|
func (csv *csvReader) readNextRow() ([]string, error) {
|
|
if csv.eof {
|
|
return nil, nil
|
|
}
|
|
row, err := csv.reader.Read()
|
|
if err != nil {
|
|
if err != io.EOF {
|
|
return nil, err
|
|
}
|
|
csv.eof = true
|
|
}
|
|
return row, nil
|
|
}
|
|
|
|
// CreateCsvDiff creates a tabular diff based on two CSV readers.
|
|
func CreateCsvDiff(diffFile *DiffFile, baseReader, headReader *csv.Reader) ([]*TableDiffSection, error) {
|
|
if baseReader != nil && headReader != nil {
|
|
return createCsvDiff(diffFile, baseReader, headReader)
|
|
}
|
|
|
|
if baseReader != nil {
|
|
return createCsvDiffSingle(baseReader, TableDiffCellDel)
|
|
}
|
|
return createCsvDiffSingle(headReader, TableDiffCellAdd)
|
|
}
|
|
|
|
// createCsvDiffSingle creates a tabular diff based on a single CSV reader. All cells are added or deleted.
|
|
func createCsvDiffSingle(reader *csv.Reader, celltype TableDiffCellType) ([]*TableDiffSection, error) {
|
|
var rows []*TableDiffRow
|
|
i := 1
|
|
for {
|
|
row, err := reader.Read()
|
|
if err != nil {
|
|
if err == io.EOF {
|
|
break
|
|
}
|
|
return nil, err
|
|
}
|
|
cells := make([]*TableDiffCell, len(row))
|
|
for j := 0; j < len(row); j++ {
|
|
if celltype == TableDiffCellDel {
|
|
cells[j] = &TableDiffCell{LeftCell: row[j], Type: celltype}
|
|
} else {
|
|
cells[j] = &TableDiffCell{RightCell: row[j], Type: celltype}
|
|
}
|
|
}
|
|
rows = append(rows, &TableDiffRow{RowIdx: i, Cells: cells})
|
|
i++
|
|
}
|
|
|
|
return []*TableDiffSection{{Rows: rows}}, nil
|
|
}
|
|
|
|
func createCsvDiff(diffFile *DiffFile, baseReader, headReader *csv.Reader) ([]*TableDiffSection, error) {
|
|
// Given the baseReader and headReader, we are going to create CSV Reader for each, baseCSVReader and b respectively
|
|
baseCSVReader, err := createCsvReader(baseReader, maxRowsToInspect)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
headCSVReader, err := createCsvReader(headReader, maxRowsToInspect)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// Initializing the mappings of base to head (a2bColMap) and head to base (b2aColMap) columns
|
|
a2bColMap, b2aColMap := getColumnMapping(baseCSVReader, headCSVReader)
|
|
|
|
// Determines how many cols there will be in the diff table, which includes deleted columns from base and added columns to base
|
|
numDiffTableCols := len(a2bColMap) + countUnmappedColumns(b2aColMap)
|
|
if len(a2bColMap) < len(b2aColMap) {
|
|
numDiffTableCols = len(b2aColMap) + countUnmappedColumns(a2bColMap)
|
|
}
|
|
|
|
// createDiffTableRow takes the row # of the `a` line and `b` line of a diff (starting from 1), 0 if the line doesn't exist (undefined)
|
|
// in the base or head respectively.
|
|
// Returns a TableDiffRow which has the row index
|
|
createDiffTableRow := func(aLineNum, bLineNum int) (*TableDiffRow, error) {
|
|
// diffTableCells is a row of the diff table. It will have a cells for added, deleted, changed, and unchanged content, thus either
|
|
// the same size as the head table or bigger
|
|
diffTableCells := make([]*TableDiffCell, numDiffTableCols)
|
|
var bRow *[]string
|
|
if bLineNum > 0 {
|
|
row, err := headCSVReader.GetRow(bLineNum - 1)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
bRow = &row
|
|
}
|
|
var aRow *[]string
|
|
if aLineNum > 0 {
|
|
row, err := baseCSVReader.GetRow(aLineNum - 1)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
aRow = &row
|
|
}
|
|
if aRow == nil && bRow == nil {
|
|
// No content
|
|
return nil, nil
|
|
}
|
|
|
|
aIndex := 0 // tracks where we are in the a2bColMap
|
|
bIndex := 0 // tracks where we are in the b2aColMap
|
|
colsAdded := 0 // incremented whenever we found a column was added
|
|
colsDeleted := 0 // incrememted whenever a column was deleted
|
|
|
|
// We loop until both the aIndex and bIndex are greater than their col map, which then we are done
|
|
for aIndex < len(a2bColMap) || bIndex < len(b2aColMap) {
|
|
// Starting from where aIndex is currently pointing, we see if the map is -1 (dleeted) and if is, create column to note that, increment, and look at the next aIndex
|
|
for aIndex < len(a2bColMap) && a2bColMap[aIndex] == -1 && (bIndex >= len(b2aColMap) || aIndex <= bIndex) {
|
|
var aCell string
|
|
if aRow != nil {
|
|
if cell, err := getCell(*aRow, aIndex); err != nil {
|
|
if err != ErrorUndefinedCell {
|
|
return nil, err
|
|
}
|
|
} else {
|
|
aCell = cell
|
|
}
|
|
}
|
|
diffTableCells[bIndex+colsDeleted] = &TableDiffCell{LeftCell: aCell, Type: TableDiffCellDel}
|
|
aIndex++
|
|
colsDeleted++
|
|
}
|
|
|
|
// aIndex is now pointing to a column that also exists in b, or is at the end of a2bColMap. If the former,
|
|
// we can just increment aIndex until it points to a -1 column or one greater than the current bIndex
|
|
for aIndex < len(a2bColMap) && a2bColMap[aIndex] != -1 {
|
|
aIndex++
|
|
}
|
|
|
|
// Starting from where bIndex is currently pointing, we see if the map is -1 (added) and if is, create column to note that, increment, and look at the next aIndex
|
|
for bIndex < len(b2aColMap) && b2aColMap[bIndex] == -1 && (aIndex >= len(a2bColMap) || bIndex < aIndex) {
|
|
var bCell string
|
|
cellType := TableDiffCellAdd
|
|
if bRow != nil {
|
|
if cell, err := getCell(*bRow, bIndex); err != nil {
|
|
if err != ErrorUndefinedCell {
|
|
return nil, err
|
|
}
|
|
} else {
|
|
bCell = cell
|
|
}
|
|
} else {
|
|
cellType = TableDiffCellDel
|
|
}
|
|
diffTableCells[bIndex+colsDeleted] = &TableDiffCell{RightCell: bCell, Type: cellType}
|
|
bIndex++
|
|
colsAdded++
|
|
}
|
|
|
|
// aIndex is now pointing to a column that also exists in a, or is at the end of b2aColMap. If the former,
|
|
// we get the a col and b col values (if they exist), figure out if they are the same or not, and if the column moved, and add it to the diff table
|
|
for bIndex < len(b2aColMap) && b2aColMap[bIndex] != -1 && (aIndex >= len(a2bColMap) || bIndex < aIndex) {
|
|
var diffTableCell TableDiffCell
|
|
|
|
var aCell *string
|
|
// get the aCell value if the aRow exists
|
|
if aRow != nil {
|
|
if cell, err := getCell(*aRow, b2aColMap[bIndex]); err != nil {
|
|
if err != ErrorUndefinedCell {
|
|
return nil, err
|
|
}
|
|
} else {
|
|
aCell = &cell
|
|
diffTableCell.LeftCell = cell
|
|
}
|
|
} else {
|
|
diffTableCell.Type = TableDiffCellAdd
|
|
}
|
|
|
|
var bCell *string
|
|
// get the bCell value if the bRow exists
|
|
if bRow != nil {
|
|
if cell, err := getCell(*bRow, bIndex); err != nil {
|
|
if err != ErrorUndefinedCell {
|
|
return nil, err
|
|
}
|
|
} else {
|
|
bCell = &cell
|
|
diffTableCell.RightCell = cell
|
|
}
|
|
} else {
|
|
diffTableCell.Type = TableDiffCellDel
|
|
}
|
|
|
|
// if both a and b have a row that exists, compare the value and determine if the row has moved
|
|
if aCell != nil && bCell != nil {
|
|
moved := ((bIndex + colsDeleted) != (b2aColMap[bIndex] + colsAdded))
|
|
if *aCell != *bCell {
|
|
if moved {
|
|
diffTableCell.Type = TableDiffCellMovedChanged
|
|
} else {
|
|
diffTableCell.Type = TableDiffCellChanged
|
|
}
|
|
} else {
|
|
if moved {
|
|
diffTableCell.Type = TableDiffCellMovedUnchanged
|
|
} else {
|
|
diffTableCell.Type = TableDiffCellUnchanged
|
|
}
|
|
diffTableCell.LeftCell = ""
|
|
}
|
|
}
|
|
|
|
// Add the diff column to the diff row
|
|
diffTableCells[bIndex+colsDeleted] = &diffTableCell
|
|
bIndex++
|
|
}
|
|
}
|
|
|
|
return &TableDiffRow{RowIdx: bLineNum, Cells: diffTableCells}, nil
|
|
}
|
|
|
|
// diffTableSections are TableDiffSections which represent the diffTableSections we get when doing a diff, each will be its own table in the view
|
|
var diffTableSections []*TableDiffSection
|
|
|
|
for i, section := range diffFile.Sections {
|
|
// Each section has multiple diffTableRows
|
|
var diffTableRows []*TableDiffRow
|
|
lines := tryMergeLines(section.Lines)
|
|
// Loop through the merged lines to get each row of the CSV diff table for this section
|
|
for j, line := range lines {
|
|
if i == 0 && j == 0 && (line[0] != 1 || line[1] != 1) {
|
|
diffTableRow, err := createDiffTableRow(1, 1)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if diffTableRow != nil {
|
|
diffTableRows = append(diffTableRows, diffTableRow)
|
|
}
|
|
}
|
|
diffTableRow, err := createDiffTableRow(line[0], line[1])
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if diffTableRow != nil {
|
|
diffTableRows = append(diffTableRows, diffTableRow)
|
|
}
|
|
}
|
|
|
|
if len(diffTableRows) > 0 {
|
|
diffTableSections = append(diffTableSections, &TableDiffSection{Rows: diffTableRows})
|
|
}
|
|
}
|
|
|
|
return diffTableSections, nil
|
|
}
|
|
|
|
// getColumnMapping creates a mapping of columns between a and b
|
|
func getColumnMapping(baseCSVReader, headCSVReader *csvReader) ([]int, []int) {
|
|
baseRow, _ := baseCSVReader.GetRow(0)
|
|
headRow, _ := headCSVReader.GetRow(0)
|
|
|
|
base2HeadColMap := []int{}
|
|
head2BaseColMap := []int{}
|
|
|
|
if baseRow != nil {
|
|
base2HeadColMap = make([]int, len(baseRow))
|
|
}
|
|
if headRow != nil {
|
|
head2BaseColMap = make([]int, len(headRow))
|
|
}
|
|
|
|
// Initializes all head2base mappings to be unmappedColumn (-1)
|
|
for i := 0; i < len(head2BaseColMap); i++ {
|
|
head2BaseColMap[i] = unmappedColumn
|
|
}
|
|
|
|
// Loops through the baseRow and see if there is a match in the head row
|
|
for i := 0; i < len(baseRow); i++ {
|
|
base2HeadColMap[i] = unmappedColumn
|
|
baseCell, err := getCell(baseRow, i)
|
|
if err == nil {
|
|
for j := 0; j < len(headRow); j++ {
|
|
if head2BaseColMap[j] == -1 {
|
|
headCell, err := getCell(headRow, j)
|
|
if err == nil && baseCell == headCell {
|
|
base2HeadColMap[i] = j
|
|
head2BaseColMap[j] = i
|
|
break
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
tryMapColumnsByContent(baseCSVReader, base2HeadColMap, headCSVReader, head2BaseColMap)
|
|
tryMapColumnsByContent(headCSVReader, head2BaseColMap, baseCSVReader, base2HeadColMap)
|
|
|
|
return base2HeadColMap, head2BaseColMap
|
|
}
|
|
|
|
// tryMapColumnsByContent tries to map missing columns by the content of the first lines.
|
|
func tryMapColumnsByContent(baseCSVReader *csvReader, base2HeadColMap []int, headCSVReader *csvReader, head2BaseColMap []int) {
|
|
for i := 0; i < len(base2HeadColMap); i++ {
|
|
headStart := 0
|
|
for base2HeadColMap[i] == unmappedColumn && headStart < len(head2BaseColMap) {
|
|
if head2BaseColMap[headStart] == unmappedColumn {
|
|
rows := min(maxRowsToInspect, max(0, min(len(baseCSVReader.buffer), len(headCSVReader.buffer))-1))
|
|
same := 0
|
|
for j := 1; j <= rows; j++ {
|
|
baseCell, baseErr := getCell(baseCSVReader.buffer[j], i)
|
|
headCell, headErr := getCell(headCSVReader.buffer[j], headStart)
|
|
if baseErr == nil && headErr == nil && baseCell == headCell {
|
|
same++
|
|
}
|
|
}
|
|
if (float32(same) / float32(rows)) > minRatioToMatch {
|
|
base2HeadColMap[i] = headStart
|
|
head2BaseColMap[headStart] = i
|
|
}
|
|
}
|
|
headStart++
|
|
}
|
|
}
|
|
}
|
|
|
|
// getCell returns the specific cell or nil if not present.
|
|
func getCell(row []string, column int) (string, error) {
|
|
if column < len(row) {
|
|
return row[column], nil
|
|
}
|
|
return "", ErrorUndefinedCell
|
|
}
|
|
|
|
// countUnmappedColumns returns the count of unmapped columns.
|
|
func countUnmappedColumns(mapping []int) int {
|
|
count := 0
|
|
for i := 0; i < len(mapping); i++ {
|
|
if mapping[i] == unmappedColumn {
|
|
count++
|
|
}
|
|
}
|
|
return count
|
|
}
|
|
|
|
// tryMergeLines maps the separated line numbers of a git diff. The result is assumed to be ordered.
|
|
func tryMergeLines(lines []*DiffLine) [][2]int {
|
|
ids := make([][2]int, len(lines))
|
|
|
|
i := 0
|
|
for _, line := range lines {
|
|
if line.Type != DiffLineSection {
|
|
ids[i][0] = line.LeftIdx
|
|
ids[i][1] = line.RightIdx
|
|
i++
|
|
}
|
|
}
|
|
|
|
ids = ids[:i]
|
|
|
|
result := make([][2]int, len(ids))
|
|
|
|
j := 0
|
|
for i = 0; i < len(ids); i++ {
|
|
if ids[i][0] == 0 {
|
|
if j > 0 && result[j-1][1] == 0 {
|
|
temp := j
|
|
for temp > 0 && result[temp-1][1] == 0 {
|
|
temp--
|
|
}
|
|
result[temp][1] = ids[i][1]
|
|
continue
|
|
}
|
|
}
|
|
result[j] = ids[i]
|
|
j++
|
|
}
|
|
|
|
return result[:j]
|
|
}
|