Merge pull request #1 from looplanguage/feat_scoped_variables

feat: scoped variables

Author: kanersps

.github/workflows/test.yaml

@@ -0,0 +1,18 @@
+on: [push, pull_request]
+name: Test
+jobs:
+  test:
+    strategy:
+      matrix:
+        go-version: [1.17.x]
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: ${{ matrix.go-version }}
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Test
+        run: go test ./...

go.mod

@@ -3,6 +3,6 @@ module github.com/looplanguage/lpvm
 go 1.17
 
 require (
-	github.com/looplanguage/compiler v0.2.0
-	github.com/looplanguage/loop v0.5.1
+	github.com/looplanguage/compiler v0.3.0
+	github.com/looplanguage/loop v0.5.2
 )

go.sum

@@ -1,18 +1,4 @@
-github.com/looplanguage/compiler v0.2.0 h1:W5jCgYdAVWtrPxmtwGIVqY2Qcz8kObTi9Fu0dQb0HIg=
-github.com/looplanguage/compiler v0.2.0/go.mod h1:D7uS6iANNHNNakYcMlrj1xw7TuBcoqImJOhLiprjRXc=
-github.com/looplanguage/loop v0.2.1 h1:nsNSOdpudJDflBpv/E1Fg7chBZ4XwTG13hwEqKNccGE=
-github.com/looplanguage/loop v0.2.1/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=
-github.com/looplanguage/loop v0.2.2 h1:ZONRZv4NllPURvJd1BdOLy+KZjWaoaEZDHVvdXXFgyo=
-github.com/looplanguage/loop v0.2.2/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=
-github.com/looplanguage/loop v0.3.0 h1:8F/XJol3pCq6ZWos0ApliAY7HTRLD23Cu9qUJP9wgng=
-github.com/looplanguage/loop v0.3.0/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=
-github.com/looplanguage/loop v0.3.1 h1:F6UKew6tc/+Ebd3OX6nIKUGUt8IXT4ZtymSPa3WADDA=
-github.com/looplanguage/loop v0.3.1/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=
-github.com/looplanguage/loop v0.3.2 h1:GeAPoMkUCNgUS0nfcEYKPcEwdSay+l5Sayhe0o72gc8=
-github.com/looplanguage/loop v0.3.2/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=
-github.com/looplanguage/loop v0.4.0 h1:HTa0CLCtaNo8ErSB43yIgzMTmgwKJiw1ckQDrb2ljG0=
-github.com/looplanguage/loop v0.4.0/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=
-github.com/looplanguage/loop v0.5.0 h1:Tyz24iVPmZExN8SIhcXUWSFFHENsLeyR9JcpvzkpZag=
-github.com/looplanguage/loop v0.5.0/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=
-github.com/looplanguage/loop v0.5.1 h1:pCWxUBPalzJQ5Ueo07dyhk15WhwAXpEvocDqShq+x6g=
-github.com/looplanguage/loop v0.5.1/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=
+github.com/looplanguage/compiler v0.3.0 h1:8DPSpT1hfKFZKJ7bC9bwVZxQEX37Y09jTpPLLCZoPzk=
+github.com/looplanguage/compiler v0.3.0/go.mod h1:ICGyV6904dEAY2tJnbCICK/0C7LMzRo8CWsQd55aRFo=
+github.com/looplanguage/loop v0.5.2 h1:ZukH3aO9Khf5PgwQF3L33ehOP7PBhZt+FKmyxe1MB7o=
+github.com/looplanguage/loop v0.5.2/go.mod h1:H1ENscrP1l2BSqSe4azQ6owr6TkBd7HgaUwDZDeUT6I=

vm/op_add.go

@@ -29,5 +29,5 @@ func (vm *VM) OpAdd() error {
 		}
 	}
 
-	return fmt.Errorf("unknown operation exception. got=%q. got=%q", left.Type(), right.Type())
+	return fmt.Errorf("unknown operation exception. got=%+v. got=%+v", left, right)
 }

vm/run.go

@@ -155,8 +155,12 @@ func (vm *VM) Run(calledOpcode RanOpcode) error {
 		case code.OpReturnValue:
 			returnValue := vm.pop()
 
-			frame := vm.popFrame()
-			vm.sp = frame.basePointer - 1
+			if vm.frameIndex != 1 {
+				frame := vm.popFrame()
+				vm.sp = frame.basePointer - 1
+			} else {
+				vm.sp = 0
+			}
 
 			err := vm.push(returnValue)
 			if err != nil {
@@ -170,6 +174,22 @@ func (vm *VM) Run(calledOpcode RanOpcode) error {
 			if err != nil {
 				return err
 			}
+		case code.OpSetVar:
+			index := code.ReadUint16(ins[ip+1:])
+
+			vm.currentFrame().ip += 2
+
+			vm.variables[index] = vm.pop()
+		case code.OpGetVar:
+			index := code.ReadUint16(ins[ip+1:])
+
+			vm.currentFrame().ip += 2
+
+			if vm.variables[index] == nil {
+				vm.push(Null)
+			} else {
+				vm.push(vm.variables[index])
+			}
 		case code.OpSetLocal:
 			localIndex := code.ReadUint8(ins[ip+1:])
 			vm.currentFrame().ip += 1

vm/vm.go

@@ -16,6 +16,7 @@ var Null = &object.Null{}
 
 type VM struct {
 	constants []object.Object
+	variables []object.Object
 
 	stack []object.Object
 	sp    int
@@ -42,6 +43,7 @@ func Create(bytecode *compiler.Bytecode) *VM {
 		globals:    make([]object.Object, GlobalsSize),
 		frames:     frames,
 		frameIndex: 1,
+		variables:  make([]object.Object, GlobalsSize),
 	}
 }
 

vm/vm_test.go

@@ -43,11 +43,11 @@ func TestBooleanExpressions(t *testing.T) {
 
 func TestConditionalExpressions(t *testing.T) {
 	tests := []vmTestCase{
-		{input: "if (true) { 10 }", expected: 10},
-		{input: "if (true) { 10 } else { 20 }", expected: 10},
-		{input: "if (false) { 10 } else { 20 }", expected: 20},
-		{input: "if (1 > 10) { 10 } else { 20 }", expected: 20},
-		{input: "if (1 > 10) { 10 } else if(true) { 400 } else { 20 }", expected: 400},
+		{input: "if (true) { return 10 }", expected: 10},
+		{input: "if (true) { return 10 } else { 20 }", expected: 10},
+		{input: "if (false) { return 10 } else { return 20 }", expected: 20},
+		{input: "if (1 > 10) { return 10 } else { return 20 }", expected: 20},
+		{input: "if (1 > 10) { return 10 } else if(true) { return 400 } else { return 20 }", expected: 400},
 		{input: "if (1 > 10) {}", expected: Null},
 		{input: "if (false) {}", expected: Null},
 	}
@@ -174,7 +174,7 @@ func TestVM_CallExpressionsWrongArguments(t *testing.T) {
 			t.Fatalf("compiler error: %s", err)
 		}
 		vm := Create(comp.Bytecode())
-		err = vm.Run()
+		err = vm.Run(nil)
 		if err == nil {
 			t.Fatalf("expected VM error but resulted in none.")
 		}
@@ -345,7 +345,7 @@ func runVmTests(t *testing.T, tests []vmTestCase) {
 		}
 
 		vm := Create(comp.Bytecode())
-		err = vm.Run()
+		err = vm.Run(nil)
 		if err != nil {
 			t.Fatalf("vm error: %s", err)
 		}