diff --git a/coverage/coverage.go b/coverage/coverage.go
index 6c555657..3076b03c 100644
--- a/coverage/coverage.go
+++ b/coverage/coverage.go
@@ -107,38 +107,6 @@ func (fc FileCoverages) FuzzyFindByFile(file string) (*FileCoverage, error) { //
 	return nil, fmt.Errorf("file name not found: %s", file)
 }
 
-func (fc FileCoverages) PathPrefix() (string, error) { //nostyle:recvtype
-	if len(fc) == 0 {
-		return "", errors.New("no file coverages")
-	}
-	p := strings.Split(filepath.Dir(filepath.ToSlash(fc[0].File)), "/")
-	for _, c := range fc {
-		d := strings.Split(filepath.Dir(filepath.ToSlash(c.File)), "/")
-		i := 0
-		for {
-			if len(p) <= i {
-				break
-			}
-			if len(d) <= i {
-				break
-			}
-			if p[i] != d[i] {
-				break
-			}
-			i += 1
-		}
-		p = p[:i]
-	}
-	s := strings.Join(p, "/")
-	if s == "" && filepath.IsAbs(fc[0].File) {
-		s = "/"
-	}
-	if s == "." {
-		s = ""
-	}
-	return s, nil
-}
-
 func (fc *FileCoverage) FindBlocksByLine(n int) BlockCoverages {
 	if fc == nil {
 		return BlockCoverages{}
diff --git a/coverage/coverage_test.go b/coverage/coverage_test.go
index 975e6d5a..76e91511 100644
--- a/coverage/coverage_test.go
+++ b/coverage/coverage_test.go
@@ -90,57 +90,6 @@ func TestCompare(t *testing.T) {
 	}
 }
 
-func TestPathPrefix(t *testing.T) {
-	tests := []struct {
-		files FileCoverages
-		want  string
-	}{
-		{
-			FileCoverages{
-				&FileCoverage{File: "file_a.go"},
-			},
-			"",
-		},
-		{
-			FileCoverages{
-				&FileCoverage{File: "path/to/file_a.go"},
-				&FileCoverage{File: "path/file_b.go"},
-			},
-			"path",
-		},
-		{
-			FileCoverages{
-				&FileCoverage{File: "/path/to/file_a.go"},
-				&FileCoverage{File: "/path/file_b.go"},
-			},
-			"/path",
-		},
-		{
-			FileCoverages{
-				&FileCoverage{File: "/path/to/foo/file_a.go"},
-				&FileCoverage{File: "/path/to/foo/bar/file_b.go"},
-			},
-			"/path/to/foo",
-		},
-		{
-			FileCoverages{
-				&FileCoverage{File: "/to/foo/file_a.go"},
-				&FileCoverage{File: "/path/to/foo/bar/file_b.go"},
-			},
-			"/",
-		},
-	}
-	for _, tt := range tests {
-		got, err := tt.files.PathPrefix()
-		if err != nil {
-			t.Fatal(err)
-		}
-		if got != tt.want {
-			t.Errorf("got %v\nwant %v", got, tt.want)
-		}
-	}
-}
-
 func TestMaxCount(t *testing.T) {
 	tests := []struct {
 		blocks BlockCoverages