From 3297f6671e2d02b34117cce204fad36ddf8f6071 Mon Sep 17 00:00:00 2001
From: Sasha Koshka <sashakoshka@tebibyte.media>
Date: Fri, 23 Feb 2024 01:08:58 -0500
Subject: [PATCH] Lexer skips over zero runes now

---
 lexer/lexer.go             | 17 +++++++++++++----
 parser/meta/parser_test.go | 13 ++++++++++++-
 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/lexer/lexer.go b/lexer/lexer.go
index df8f6b9..8d3734c 100644
--- a/lexer/lexer.go
+++ b/lexer/lexer.go
@@ -5,6 +5,7 @@ import "io"
 import "fmt"
 import "bufio"
 import "unicode"
+import "unicode/utf8"
 import "git.tebibyte.media/fspl/fspl/errors"
 
 // TokenKind is an enumeration of all tokens the FSPL compiler recognizes.
@@ -134,7 +135,8 @@ type fsplLexer struct {
 	filename    string
 	lineScanner *bufio.Scanner
 	rune        rune
-	runeLine    []rune
+	line        string
+	lineFood    string
 
 	offset   int
 	row      int
@@ -314,10 +316,11 @@ func (this *fsplLexer) nextInternal () (token Token, err error) {
 }
 
 func (this *fsplLexer) nextRune () error {
-	if this.column >= len(this.runeLine) {
+	if this.lineFood == "" {
 		ok := this.lineScanner.Scan()
 		if ok {
-			this.runeLine = []rune(this.lineScanner.Text())
+			this.line     = this.lineScanner.Text()
+			this.lineFood = this.line
 			this.rune     = '\n'
 			this.column   = 0
 			this.row      ++
@@ -331,7 +334,13 @@ func (this *fsplLexer) nextRune () error {
 			}
 		}
 	} else {
-		this.rune = this.runeLine[this.column]
+		var ch   rune
+		var size int
+		for ch == 0 && this.lineFood != "" {
+			ch, size = utf8.DecodeRuneInString(this.lineFood)
+			this.lineFood = this.lineFood[size:]
+		}
+		this.rune = ch
 		this.column ++
 	}
 
diff --git a/parser/meta/parser_test.go b/parser/meta/parser_test.go
index cad0fde..fff8fd5 100644
--- a/parser/meta/parser_test.go
+++ b/parser/meta/parser_test.go
@@ -9,7 +9,8 @@ testString (test,
 + 'io'
 + '../io' customIo`,
 // input
-`'5a8353f8cad84604be6029a2575996bc'
+`
+'5a8353f8cad84604be6029a2575996bc'
 + 'io'
 + '../io' customIo
 `)
@@ -27,3 +28,13 @@ testString (test,
 + 'io'  + '../io'     customIo
 `)
 }
+
+func TestOnlyUUID (test *testing.T) {
+testString (test,
+// correct
+`'5a8353f8-cad8-4604-be60-29a2575996bc'`,
+// input
+`
+'5a8353f8cad84604be6029a2575996bc'
+`)
+}