Re-wrote from scratch in Golang

- Re-implemented the project in Golang, and deprecated Python entirely
- Implemented several new, long-requested features
- Refactored cheatsheets into a separate repository

internal/sheets/load.go

@@ -0,0 +1,77 @@
+package sheets
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	cp "github.com/cheat/cheat/internal/cheatpath"
+	"github.com/cheat/cheat/internal/sheet"
+)
+
+// Load produces a map of cheatsheet titles to filesystem paths
+func Load(cheatpaths []cp.Cheatpath) ([]map[string]sheet.Sheet, error) {
+
+	// create a slice of maps of sheets. This structure will store all sheets
+	// that are associated with each cheatpath.
+	sheets := make([]map[string]sheet.Sheet, len(cheatpaths))
+
+	// iterate over each cheatpath
+	for _, cheatpath := range cheatpaths {
+
+		// vivify the map of cheatsheets on this specific cheatpath
+		pathsheets := make(map[string]sheet.Sheet)
+
+		// recursively iterate over the cheatpath, and load each cheatsheet
+		// encountered along the way
+		err := filepath.Walk(
+			cheatpath.Path, func(
+				path string,
+				info os.FileInfo,
+				err error) error {
+
+				// fail if an error occurred while walking the directory
+				if err != nil {
+					return fmt.Errorf("error walking path: %v", err)
+				}
+
+				// don't register directories as cheatsheets
+				if info.IsDir() {
+					return nil
+				}
+
+				// calculate the cheatsheet's "title" (the phrase with which it may be
+				// accessed. Eg: `cheat tar` - `tar` is the title)
+				title := strings.TrimPrefix(
+					strings.TrimPrefix(path, cheatpath.Path),
+					"/",
+				)
+
+				// ignore dotfiles. Otherwise, we'll likely load .git/*
+				if strings.HasPrefix(title, ".") {
+					return nil
+				}
+
+				// parse the cheatsheet file into a `sheet` struct
+				s, err := sheet.New(title, path, cheatpath.Tags, cheatpath.ReadOnly)
+				if err != nil {
+					return fmt.Errorf("could not create sheet: %v", err)
+				}
+
+				// register the cheatsheet on its cheatpath, keyed by its title
+				pathsheets[title] = s
+				return nil
+			})
+		if err != nil {
+			return sheets, fmt.Errorf("failed to load cheatsheets: %v", err)
+		}
+
+		// store the sheets on this cheatpath alongside the other cheatsheets on
+		// other cheatpaths
+		sheets = append(sheets, pathsheets)
+	}
+
+	// return the cheatsheets, grouped by cheatpath
+	return sheets, nil
+}