Implemented function scanning

src/scanner/scanFile.go

@@ -0,0 +1,52 @@
+package scanner
+
+import (
+	"os"
+
+	"git.urbach.dev/cli/q/src/errors"
+	"git.urbach.dev/cli/q/src/fs"
+	"git.urbach.dev/cli/q/src/token"
+)
+
+// scanFile scans a single file.
+func (s *scanner) scanFile(path string, pkg string) error {
+	contents, err := os.ReadFile(path)
+
+	if err != nil {
+		return err
+	}
+
+	tokens := token.Tokenize(contents)
+
+	file := &fs.File{
+		Path:    path,
+		Package: pkg,
+		Bytes:   contents,
+		Tokens:  tokens,
+	}
+
+	s.files <- file
+
+	for i := 0; i < len(tokens); i++ {
+		switch tokens[i].Kind {
+		case token.NewLine:
+		case token.Comment:
+		case token.Identifier:
+			i, err = s.scanFunction(file, tokens, i)
+		case token.Import:
+			i, err = s.scanImport(file, tokens, i)
+		case token.EOF:
+			return nil
+		case token.Invalid:
+			return errors.New(&errors.InvalidCharacter{Character: tokens[i].String(file.Bytes)}, file, tokens[i].Position)
+		default:
+			return errors.New(&errors.InvalidTopLevel{Instruction: tokens[i].String(file.Bytes)}, file, tokens[i].Position)
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}