Squashed 'go-enry/' content from commit 7e3a9a7

git-subtree-dir: go-enry
git-subtree-split: 7e3a9a7241

internal/code-generator/generator/filenames.go

@@ -0,0 +1,101 @@
+package generator
+
+import (
+	"bytes"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"text/template"
+
+	yaml "gopkg.in/yaml.v2"
+)
+
+// Filenames reads from fileToParse and builds source file from tmplPath. It complies with type File signature.
+func Filenames(fileToParse, samplesDir, outPath, tmplPath, tmplName, commit string) error {
+	data, err := ioutil.ReadFile(fileToParse)
+	if err != nil {
+		return err
+	}
+
+	languages := make(map[string]*languageInfo)
+	if err := yaml.Unmarshal(data, &languages); err != nil {
+		return err
+	}
+
+	if err := walkSamplesFilenames(samplesDir, languages); err != nil {
+		return err
+	}
+
+	languagesByFilename := buildFilenameLanguageMap(languages)
+
+	buf := &bytes.Buffer{}
+	if err := executeFilenamesTemplate(buf, languagesByFilename, tmplPath, tmplName, commit); err != nil {
+		return err
+	}
+
+	return formatedWrite(outPath, buf.Bytes())
+}
+
+func walkSamplesFilenames(samplesDir string, languages map[string]*languageInfo) error {
+	const filenamesDir = "filenames"
+	var language string
+	err := filepath.Walk(samplesDir, func(path string, f os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+
+		if f.IsDir() {
+			if f.Name() != filenamesDir {
+				language = f.Name()
+			}
+
+			return nil
+		}
+
+		parentDir := filepath.Base(filepath.Dir(path))
+		if parentDir != filenamesDir {
+			return nil
+		}
+
+		info, ok := languages[language]
+		if !ok {
+			info = &languageInfo{Filenames: []string{}}
+		}
+
+		for _, filename := range info.Filenames {
+			if filename == f.Name() {
+				return nil
+			}
+		}
+
+		info.Filenames = append(info.Filenames, f.Name())
+
+		return nil
+	})
+
+	return err
+}
+
+func buildFilenameLanguageMap(languages map[string]*languageInfo) map[string][]string {
+	filenameLangMap := make(map[string][]string)
+	for lang, langInfo := range languages {
+		for _, filename := range langInfo.Filenames {
+			filenameLangMap[filename] = append(filenameLangMap[filename], lang)
+		}
+	}
+
+	return filenameLangMap
+}
+
+func executeFilenamesTemplate(out io.Writer, languagesByFilename map[string][]string, tmplPath, tmplName, commit string) error {
+	fmap := template.FuncMap{
+		"formatStringSlice": func(slice []string) string {
+			sort.Strings(slice)
+			return `"` + strings.Join(slice, `","`) + `"`
+		},
+	}
+	return executeTemplate(out, tmplName, tmplPath, commit, fmap, languagesByFilename)
+}