feat: caster implementation switched to actual shell interpreter

internal/adapters/caster/caster.go

@@ -7,8 +7,9 @@ import (
 	"fmt"
 	errors2 "github.com/abelith/spellbook/internal/errors"
 	"github.com/abelith/spellbook/internal/models"
-	"github.com/google/shlex"
-	"os/exec"
+	"io"
+	"mvdan.cc/sh/v3/interp"
+	"mvdan.cc/sh/v3/syntax"
 	"text/template"
 	"time"
 )
@@ -16,18 +17,8 @@ import (
 type SpellCaster struct{}
 
 func (sc *SpellCaster) Cast(ctx context.Context, cast models.SpellCast) (models.CastResult, error) {
-	args, err := renderSpell(cast)
-	if err != nil {
-		return models.CastResult{}, err
-	}
-
-	cmd := exec.CommandContext(ctx, args[0], args[1:]...)
-	cmd.Stdin = cast.Stdin
-	cmd.Stdout = cast.Stdout
-	cmd.Stderr = cast.Stderr
-
 	start := time.Now()
-	err = cmd.Run()
+	err := runSpell(ctx, &cast)
 	duration := time.Since(start)
 
 	res := models.CastResult{
@@ -35,29 +26,47 @@ func (sc *SpellCaster) Cast(ctx context.Context, cast models.SpellCast) (models.
 	}
 
 	if err != nil {
-		var exitErr *exec.ExitError
+		var exitErr *interp.ExitStatus
 		if errors.As(err, &exitErr) {
-			res.ExitCode = exitErr.ExitCode()
+			res.ExitCode = int(*exitErr)
 			res.Err = err
 			return res, nil
 		}
 		return res, fmt.Errorf("%w: %w", errors2.ErrFailedToCast, err)
 	}
 
-	res.ExitCode = 0
 	return res, nil
 }
 
-func renderSpell(cast models.SpellCast) ([]string, error) {
+func renderSpell(cast *models.SpellCast) (io.Reader, error) {
 	tmpl, err := template.New(cast.Spell.Name).Option("missingkey=error").Parse(cast.Spell.Spell)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("%w: %w", errors2.ErrTemplateFailed, err)
 	}
 
 	buf := bytes.NewBuffer(nil)
 	if err := tmpl.Execute(buf, cast.Args); err != nil {
-		return nil, err
+		return nil, fmt.Errorf("%w: %w", errors2.ErrTemplateFailed, err)
 	}
 
-	return shlex.Split(buf.String())
+	return buf, nil
+}
+
+func runSpell(ctx context.Context, cast *models.SpellCast) error {
+	r, err := renderSpell(cast)
+	if err != nil {
+		return err
+	}
+
+	node, err := syntax.NewParser().Parse(r, cast.Spell.Name)
+	if err != nil {
+		return fmt.Errorf("failed to parse spell: %w", err)
+	}
+
+	runner, err := interp.New(interp.StdIO(cast.Stdin, cast.Stdout, cast.Stderr))
+	if err != nil {
+		return fmt.Errorf("failed to run spell: %w", err)
+	}
+
+	return runner.Run(ctx, node)
 }