From 64a351a9cc6dd2d3b59d8c84b554dd2e35a946f5 Mon Sep 17 00:00:00 2001
From: Dimitri Sokolyuk <sokolyuk@gmail.com>
Date: Thu, 1 Jun 2017 18:08:39 +0200
Subject: [PATCH 1/2] Prevent panic in case there are no files to check.

---
 lint.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lint.go b/lint.go
index 5b85d8e8..9de6e258 100644
--- a/lint.go
+++ b/lint.go
@@ -279,6 +279,9 @@ func (p *pkg) typeCheck() error {
 		anyFile = f
 		astFiles = append(astFiles, f.f)
 	}
+	if anyFile == nil {
+		return nil
+	}
 	pkg, err := config.Check(anyFile.f.Name.Name, p.fset, astFiles, info)
 	// Remember the typechecking info, even if config.Check failed,
 	// since we will get partial information.

From 37dcb65c2314b68bb8acc4522f6b159c61634b6e Mon Sep 17 00:00:00 2001
From: Dimitri Sokolyuk <sokolyuk@gmail.com>
Date: Thu, 1 Jun 2017 18:46:09 +0200
Subject: [PATCH 2/2] Abort early

---
 lint.go | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/lint.go b/lint.go
index 9de6e258..fb47da00 100644
--- a/lint.go
+++ b/lint.go
@@ -82,9 +82,6 @@ func (l *Linter) Lint(filename string, src []byte) ([]Problem, error) {
 // LintFiles lints a set of files of a single package.
 // The argument is a map of filename to source.
 func (l *Linter) LintFiles(files map[string][]byte) ([]Problem, error) {
-	if len(files) == 0 {
-		return nil, nil
-	}
 	pkg := &pkg{
 		fset:  token.NewFileSet(),
 		files: make(map[string]*file),
@@ -111,6 +108,9 @@ func (l *Linter) LintFiles(files map[string][]byte) ([]Problem, error) {
 			filename: filename,
 		}
 	}
+	if len(pkg.files) == 0 {
+		return nil, nil
+	}
 	return pkg.lint(), nil
 }
 
@@ -279,9 +279,6 @@ func (p *pkg) typeCheck() error {
 		anyFile = f
 		astFiles = append(astFiles, f.f)
 	}
-	if anyFile == nil {
-		return nil
-	}
 	pkg, err := config.Check(anyFile.f.Name.Name, p.fset, astFiles, info)
 	// Remember the typechecking info, even if config.Check failed,
 	// since we will get partial information.