From 743f7aa332286a42de83b6c36f0a0e5c4927e65c Mon Sep 17 00:00:00 2001
From: xdrm-brackets <xdrm.brackets.dev@gmail.com>
Date: Sat, 23 Nov 2019 01:04:35 +0100
Subject: [PATCH] create coverage +reader

---
 coverage/reader.go | 116 +++++++++++++++++++++++++++++++++++++++++++++
 coverage/types.go  |  43 +++++++++++++++++
 2 files changed, 159 insertions(+)
 create mode 100644 coverage/reader.go
 create mode 100644 coverage/types.go

diff --git a/coverage/reader.go b/coverage/reader.go
new file mode 100644
index 0000000..2286676
--- /dev/null
+++ b/coverage/reader.go
@@ -0,0 +1,116 @@
+package coverage
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+)
+
+// Parse creates a coverage files struct from a coverage file format
+// you must provide @gopkg which is the package name
+func Parse(r io.Reader, gopkg string) (*Files, error) {
+	reader := bufio.NewReader(r)
+	eof := false
+	var n uint = 0
+
+	files := &Files{
+		files:       make(map[string]File),
+		packagePath: gopkg,
+	}
+
+	// read loop
+	for true {
+		n++
+		if eof {
+			break
+		}
+
+		notrim, err := reader.ReadString('\n')
+		if err == io.EOF {
+			if len(notrim) > 0 {
+				eof = true
+			} else {
+				break
+			}
+		}
+
+		line := strings.Trim(notrim, " \t\r\n")
+		if len(line) < 1 {
+			continue
+		}
+
+		// ignore first line
+		if n == 1 && line == "mode: set" {
+			continue
+		}
+
+		// extract features from line
+		var cover = Coverage{}
+
+		// format: filename:startLine.startColumn,endLine.endColumn occurences count
+		splitFile := strings.Split(line, ":")
+		if len(splitFile) != 2 {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+		filename := splitFile[0]
+		if !strings.HasPrefix(filename, gopkg) {
+			return nil, fmt.Errorf("invalid package name '%s' on line %d", gopkg, n)
+		}
+		filename = strings.TrimPrefix(filename, gopkg)
+		if len(filename) < 2 {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+		// remove starting '/'
+		if filename[0] == '/' {
+			filename = filename[1:]
+		}
+
+		splitSpace := strings.Split(splitFile[1], " ")
+		if len(splitSpace) != 3 {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+
+		separators := strings.Split(splitSpace[0], ",")
+		if len(separators) != 2 {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+
+		splitStart := strings.Split(separators[0], ".")
+		if len(splitStart) != 2 {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+		cover.StartLine, err = strconv.ParseUint(splitStart[0], 10, 64)
+		if err != nil {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+		cover.StartColumn, err = strconv.ParseUint(splitStart[1], 10, 64)
+		if err != nil {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+
+		splitEnd := strings.Split(separators[1], ".")
+		if len(splitEnd) != 2 {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+		cover.EndLine, err = strconv.ParseUint(splitEnd[0], 10, 64)
+		if err != nil {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+		cover.EndColumn, err = strconv.ParseUint(splitEnd[1], 10, 64)
+		if err != nil {
+			return nil, fmt.Errorf("invalid format line %d", n)
+		}
+
+		// append to files
+		_, isset := files.files[filename]
+		if !isset {
+			files.files[filename] = make(File, 0)
+		}
+		files.files[filename] = append(files.files[filename], cover)
+
+	}
+
+	return files, nil
+}
diff --git a/coverage/types.go b/coverage/types.go
new file mode 100644
index 0000000..a04e36b
--- /dev/null
+++ b/coverage/types.go
@@ -0,0 +1,43 @@
+package coverage
+
+import "strings"
+
+// Files contains coverage files indexed by file path
+type Files struct {
+	packagePath string
+	files       map[string]File
+}
+
+// File represents every coverage chunk for a file
+type File []Coverage
+
+// Coverage represents a covered chunk
+type Coverage struct {
+	StartLine   uint64
+	StartColumn uint64
+	EndLine     uint64
+	EndColumn   uint64
+}
+
+// GetFile returns the formatted coverage for the file located at @path
+func (f *Files) GetFile(path string) []File {
+	var isDir bool = !strings.HasSuffix(path, ".go")
+
+	files := make([]File, 0)
+
+	// search in coverage files
+	for fPath, fileCoverage := range f.files {
+
+		if !isDir && path == fPath {
+			files = append(files, fileCoverage)
+			// if not directory search, stop at first result
+			break
+		}
+
+		if isDir && (path == "." || strings.HasPrefix(fPath, path)) {
+			files = append(files, fileCoverage)
+		}
+	}
+
+	return files
+}