gopkg.in/alecthomas/gometalinter.v3@v3.0.0/_linters/src/github.com/walle/lll/lll.go (about)

     1  // Package lll provides validation functions regarding line length
     2  package lll
     3  
     4  import (
     5  	"bufio"
     6  	"fmt"
     7  	"io"
     8  	"io/ioutil"
     9  	"net/http"
    10  	"os"
    11  	"path/filepath"
    12  	"regexp"
    13  	"strings"
    14  	"unicode/utf8"
    15  )
    16  
    17  // ShouldSkip checks the input and determines if the path should be skipped.
    18  // Use the SkipList to quickly skip paths.
    19  // All directories are skipped, only files are processed.
    20  // If GoOnly is supplied check that the file is a go file.
    21  // Otherwise check so the file is a "text file".
    22  func ShouldSkip(path string, isDir bool, skipList []string,
    23  	goOnly bool) (bool, error) {
    24  
    25  	name := filepath.Base(path)
    26  	for _, d := range skipList {
    27  		if name == d {
    28  			if isDir {
    29  				return true, filepath.SkipDir
    30  			}
    31  			return true, nil
    32  		}
    33  	}
    34  	if isDir {
    35  		return true, nil
    36  	}
    37  
    38  	if goOnly {
    39  		if !strings.HasSuffix(path, ".go") {
    40  			return true, nil
    41  		}
    42  	} else {
    43  		b, err := ioutil.ReadFile(path)
    44  		if err != nil {
    45  			return true, err
    46  		}
    47  		m := http.DetectContentType(b)
    48  		if !strings.Contains(m, "text/") {
    49  			return true, nil
    50  		}
    51  	}
    52  
    53  	return false, nil
    54  }
    55  
    56  // ProcessFile checks all lines in the file and writes an error if the line
    57  // length is greater than MaxLength.
    58  func ProcessFile(w io.Writer, path string, maxLength, tabWidth int,
    59  	exclude *regexp.Regexp) error {
    60  	f, err := os.Open(path)
    61  	if err != nil {
    62  		return err
    63  	}
    64  	defer func() {
    65  		err := f.Close()
    66  		if err != nil {
    67  			fmt.Printf("Error closing file: %s\n", err)
    68  		}
    69  	}()
    70  
    71  	return Process(f, w, path, maxLength, tabWidth, exclude)
    72  }
    73  
    74  // Process checks all lines in the reader and writes an error if the line length
    75  // is greater than MaxLength.
    76  func Process(r io.Reader, w io.Writer, path string, maxLength, tabWidth int,
    77  	exclude *regexp.Regexp) error {
    78  	spaces := strings.Repeat(" ", tabWidth)
    79  	l := 1
    80  	s := bufio.NewScanner(r)
    81  	for s.Scan() {
    82  		t := s.Text()
    83  		t = strings.Replace(t, "\t", spaces, -1)
    84  		c := utf8.RuneCountInString(t)
    85  		if c > maxLength {
    86  			if exclude != nil {
    87  				if exclude.MatchString(t) {
    88  					continue
    89  				}
    90  			}
    91  			fmt.Fprintf(w, "%s:%d: line is %d characters\n", path, l, c)
    92  		}
    93  		l++
    94  	}
    95  
    96  	if err := s.Err(); err != nil {
    97  		return err
    98  	}
    99  
   100  	return nil
   101  }