1 files changed, 123 insertions, 0 deletions
diff --git a/source/sourceSpec.go b/source/sourceSpec.go
new file mode 100644
index 000000000..dc44994a8
--- /dev/null
+++ b/source/sourceSpec.go
@@ -0,0 +1,123 @@
+// Copyright 2023 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package source contains the types and functions related to source files.
+package source
+
+import (
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"github.com/gohugoio/hugo/hugofs/glob"
+
+	"github.com/spf13/afero"
+
+	"github.com/gohugoio/hugo/helpers"
+)
+
+// SourceSpec abstracts language-specific file creation.
+// TODO(bep) rename to Spec
+type SourceSpec struct {
+	*helpers.PathSpec
+
+	SourceFs afero.Fs
+
+	shouldInclude func(filename string) bool
+}
+
+// NewSourceSpec initializes SourceSpec using languages the given filesystem and PathSpec.
+func NewSourceSpec(ps *helpers.PathSpec, inclusionFilter *glob.FilenameFilter, fs afero.Fs) *SourceSpec {
+
+	shouldInclude := func(filename string) bool {
+		if !inclusionFilter.Match(filename, false) {
+			return false
+		}
+		if ps.Cfg.IgnoreFile(filename) {
+			return false
+		}
+
+		return true
+	}
+
+	return &SourceSpec{shouldInclude: shouldInclude, PathSpec: ps, SourceFs: fs}
+}
+
+// IgnoreFile returns whether a given file should be ignored.
+func (s *SourceSpec) IgnoreFile(filename string) bool {
+	if filename == "" {
+		if _, ok := s.SourceFs.(*afero.OsFs); ok {
+			return true
+		}
+		return false
+	}
+
+	base := filepath.Base(filename)
+
+	if len(base) > 0 {
+		first := base[0]
+		last := base[len(base)-1]
+		if first == '.' ||
+			first == '#' ||
+			last == '~' {
+			return true
+		}
+	}
+
+	if !s.shouldInclude(filename) {
+		return true
+	}
+
+	if runtime.GOOS == "windows" {
+		// Also check the forward slash variant if different.
+		unixFilename := filepath.ToSlash(filename)
+		if unixFilename != filename {
+			if !s.shouldInclude(unixFilename) {
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+// IsRegularSourceFile returns whether filename represents a regular file in the
+// source filesystem.
+func (s *SourceSpec) IsRegularSourceFile(filename string) (bool, error) {
+	fi, err := helpers.LstatIfPossible(s.SourceFs, filename)
+	if err != nil {
+		return false, err
+	}
+
+	if fi.IsDir() {
+		return false, nil
+	}
+
+	if fi.Mode()&os.ModeSymlink == os.ModeSymlink {
+		link, err := filepath.EvalSymlinks(filename)
+		if err != nil {
+			return false, err
+		}
+
+		fi, err = helpers.LstatIfPossible(s.SourceFs, link)
+		if err != nil {
+			return false, err
+		}
+
+		if fi.IsDir() {
+			return false, nil
+		}
+	}
+
+	return true, nil
+}