Merge pull request #123 from skx/122-newline

122 - Fix swallowline

.github/build

@@ -3,6 +3,9 @@
 # The basename of our binary
 BASE="gobasic"
 
+# I don't even ..
+go env -w GOFLAGS="-buildvcs=false"
+
 # Get the dependencies
 go mod init
 

.github/run-tests.sh

@@ -1,5 +1,10 @@
 #!/bin/bash
 
+
+# I don't even ..
+go env -w GOFLAGS="-buildvcs=false"
+
+
 # Install the tools we use to test our code-quality.
 #
 # Here we setup the tools to install only if the "CI" environmental variable

eval/eval.go

@@ -10,7 +10,6 @@
 // as REM, DATA, READ, etc.  Things that could be pushed outside the core,
 // such as the maths-primitives (SIN, COS, TAN, etc) have been moved into
 // their own package to keep this as simple and readable as possible.
-//
 package eval
 
 import (
@@ -597,7 +596,8 @@ func (e *Interpreter) factor() object.Object {
 }
 
 // terminal - handles parsing of the form
-//  ARG1 OP ARG2
+//
+//	ARG1 OP ARG2
 //
 // See also expr() which is similar.
 func (e *Interpreter) term() object.Object {
@@ -773,7 +773,9 @@ func (e *Interpreter) term() object.Object {
 }
 
 // expression - handles parsing of the form
-//  ARG1 OP ARG2
+//
+//	ARG1 OP ARG2
+//
 // See also term() which is similar.
 func (e *Interpreter) expr(allowBinOp bool) object.Object {
 
@@ -1811,8 +1813,9 @@ func (e *Interpreter) runGOTO() error {
 // runINPUT handles input of numbers from the user.
 //
 // NOTE:
-//   INPUT "Foo", a   -> Reads an integer
-//   INPUT "Foo", a$  -> Reads a string
+//
+//	INPUT "Foo", a   -> Reads an integer
+//	INPUT "Foo", a$  -> Reads a string
 func (e *Interpreter) runINPUT() error {
 
 	// Skip the INPUT-instruction
@@ -1909,10 +1912,9 @@ func (e *Interpreter) runINPUT() error {
 //
 // Here we _only_ allow:
 //
-//  IF $EXPR THEN $STATEMENT ELSE $STATEMENT NEWLINE
+//	IF $EXPR THEN $STATEMENT ELSE $STATEMENT NEWLINE
 //
 // $STATEMENT will only be a single expression
-//
 func (e *Interpreter) runIF() error {
 
 	// Bump past the IF token
@@ -2291,19 +2293,21 @@ func (e *Interpreter) runNEXT() error {
 //
 // This is used by:
 //
-//  REM
-//  DATA
-//  DEF FN
-//
+//	REM
+//	DATA
+//	DEF FN
 func (e *Interpreter) swallowLine() error {
 
-	run := true
+	// Look forwards
+	for e.offset < len(e.program) {
 
-	for e.offset < len(e.program) && run {
+		// If the token is a newline, or EOF we're done
 		tok := e.program[e.offset]
 		if tok.Type == token.NEWLINE || tok.Type == token.EOF {
-			run = false
+			return nil
 		}
+
+		// Otherwise keep going.
 		e.offset++
 	}
 
@@ -2786,7 +2790,6 @@ func (e *Interpreter) GetTrace() bool {
 // SetVariable sets the contents of a variable in the interpreter environment.
 //
 // Useful for testing/embedding.
-//
 func (e *Interpreter) SetVariable(id string, val object.Object) {
 	e.vars.Set(id, val)
 }
@@ -2844,7 +2847,6 @@ func (e *Interpreter) SetArrayVariable(id string, index []int, val object.Object
 // GetVariable returns the contents of the given variable.
 //
 // Useful for testing/embedding.
-//
 func (e *Interpreter) GetVariable(id string) object.Object {
 
 	val := e.vars.Get(id)
@@ -2888,7 +2890,6 @@ func (e *Interpreter) GetArrayVariable(id string, index []int) object.Object {
 // be called from the users' BASIC program.
 //
 // Useful for embedding.
-//
 func (e *Interpreter) RegisterBuiltin(name string, nArgs int, ft builtin.Signature) {
 
 	//

eval/eval_test.go

@@ -8,6 +8,7 @@ import (
 	"testing"
 
 	"github.com/skx/gobasic/object"
+	"github.com/skx/gobasic/token"
 	"github.com/skx/gobasic/tokenizer"
 )
 
@@ -1730,3 +1731,38 @@ func TestZero(t *testing.T) {
 	}
 
 }
+
+// TestSwallowLine tests we don't eat too many tokens in the processing
+// of newlines.
+func TestSwallowLine(t *testing.T) {
+
+	input := `10 REM "This is a test"  So is this
+20 PRINT "OK"
+`
+
+	tokener := tokenizer.New(input)
+	e, err := New(tokener)
+	if err != nil {
+		t.Errorf("Error parsing %s - %s", input, err.Error())
+	}
+
+	// We start at offset 0
+	if e.offset != 0 {
+		t.Fatalf("we didn't start at the beginning")
+	}
+
+	err = e.swallowLine()
+	if err != nil {
+		t.Fatalf("error eating line")
+	}
+
+	// offset should now be bigger
+	if e.offset != 6 {
+		t.Fatalf("our offset was %d not %d", e.offset, 6)
+	}
+
+	// And we should have a newline as the next token
+	if e.program[e.offset].Type != token.NEWLINE {
+		t.Fatalf("did not get a line number got %v", e.program[e.offset])
+	}
+}