Unmarshal: WIP

Signed-off-by: Alejandro Mery <amery@jpi.io>

go.mod

@@ -5,7 +5,7 @@ go 1.19
 replace asciigoat.org/core => ../core
 
 require (
-	asciigoat.org/core v0.3.4
+	asciigoat.org/core v0.3.2
 	github.com/mgechev/revive v1.3.3
 )
 

parser/lexer.go

@@ -1,10 +1,6 @@
 package parser
 
-import (
+import "asciigoat.org/core/lexer"
-	"log"
-
-	"asciigoat.org/core/lexer"
-)
 
 // Run parses the source
 func (p *Parser) Run() error {
@@ -19,81 +15,44 @@ func (p *Parser) lexStart() (lexer.StateFn, error) {
 		r, _, err := p.src.ReadRune()
 		switch {
 		case err != nil:
-			// read error
 			return p.emitError("", err)
-		case IsNewLine(r):
+		case r == '\n':
 			// new line
-			p.lexNewLine(r)
+			r2, _, err := p.src.ReadRune()
+			switch {
+			case err == nil && r2 == '\r':
+				// MAC new line
+			case err == nil:
+				// UNIX new line
+				p.src.UnreadRune()
+			}
+
 			p.src.Discard()
 			p.pos.StepLine()
-		case IsSpace(r):
+		case r == '\r':
+			// new line
+			r2, _, err := p.src.ReadRune()
+			switch {
+			case err == nil && r2 == '\n':
+				// DOS new line
+			case err == nil:
+				// incomplete CRLN
+				p.src.UnreadRune()
+				return p.emitInvalidRune(r2)
+			}
+
+			p.src.Discard()
+			p.pos.StepLine()
+		case p.IsSpace(r):
 			// whitespace
 			p.src.Discard()
 			p.pos.Step()
-		case IsCommentStart(r):
+		case p.IsCommentStart(r):
 			// switch to comment lexer
 			p.src.UnreadRune()
 			return p.lexComment, nil
-		case IsSectionStart(r):
-			// section
-			p.src.Discard()
-			p.pos.Step()
-			return p.lexSectionStart, nil
-		default:
-			// entry
-			p.src.UnreadRune()
-			return p.lexEntryStart, nil
 		}
 	}
 }
 
-func (p *Parser) lexNewLine(r1 rune) {
+func (p *Parser) lexComment() (lexer.StateFn, error)
-	// r1 is warrantied to be either \n or \r
-	r2, _, err := p.src.ReadRune()
-
-	switch r1 {
-	case '\r':
-		switch {
-		case r2 == '\n':
-			// CR LN
-		case err == nil:
-			// CR
-			p.src.UnreadRune()
-		default:
-			// CR EOF
-		}
-	case '\n':
-		switch {
-		case r2 == '\r':
-			// LN CR
-		case err == nil:
-			// LN
-			p.src.UnreadRune()
-		default:
-			// LN EOF
-		}
-	default:
-		panic("unreachable")
-	}
-}
-
-func (p *Parser) lexComment() (lexer.StateFn, error) {
-	// until the end of the line
-	p.src.AcceptAll(IsNotNewLine)
-
-	err := p.OnComment(p.pos, p.src.Emit())
-	return p.lexStart, err
-}
-
-func (*Parser) lexSectionStart() (lexer.StateFn, error) { return nil, nil }
-func (*Parser) lexEntryStart() (lexer.StateFn, error)   { return nil, nil }
-
-func (p *Parser) lexToken() (lexer.StateFn, error) {
-	p.src.AcceptAll(IsNotSpace)
-
-	s := p.src.Emit()
-	log.Printf("%s: %s: %q", p.pos, "token", s)
-	p.pos.StepN(len(s))
-
-	return p.lexStart, nil
-}

parser/lexer_runes.go

@@ -1,20 +1,17 @@
 package parser
 
-import "asciigoat.org/core/lexer"
+import "unicode"
 
-var (
+func (*Parser) IsSpace(r rune) bool {
-	// IsNewLine tells if a rune represents a line break or the start of one
+	return unicode.IsSpace(r)
-	IsNewLine = lexer.NewIsIn("\n\r")
+}
-	// IsSpace tells if a rune is considered whitespace by unicode
+
-	IsSpace = lexer.IsSpace
+func (*Parser) IsCommentStart(r rune) bool {
-	// IsNotNewLine tells if a rune is anything other than line breaks
+	// TODO: use Parser options
-	IsNotNewLine = lexer.NewIsNot(IsNewLine)
+	switch r {
-	// IsNotSpace tells if a rune is anything other than whitespace
+	case ';', '#':
-	IsNotSpace = lexer.NewIsNot(IsSpace)
+		return true
-
+	default:
-	IsCommentStart = lexer.NewIsIn(";#")
+		return false
-)
+	}
-
-func IsSectionStart(r rune) bool {
-	return r == '['
 }