From 457e7e006a5c7d7a7fe20718dc2da1fbdc7df6de Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <evgeniy@nspcc.ru>
Date: Thu, 2 Apr 2020 16:36:11 +0300
Subject: [PATCH] compiler: support exporting method variables in debug info

---
 pkg/compiler/codegen.go    |  8 ++++++++
 pkg/compiler/debug.go      |  6 ++++++
 pkg/compiler/debug_test.go | 14 ++++++++++++++
 pkg/compiler/func_scope.go |  3 +++
 4 files changed, 31 insertions(+)

diff --git a/pkg/compiler/codegen.go b/pkg/compiler/codegen.go
index 612ae60de..e5c8b7e32 100644
--- a/pkg/compiler/codegen.go
+++ b/pkg/compiler/codegen.go
@@ -286,6 +286,9 @@ func (c *codegen) Visit(node ast.Node) ast.Visitor {
 		for _, spec := range n.Specs {
 			switch t := spec.(type) {
 			case *ast.ValueSpec:
+				for _, id := range t.Names {
+					c.registerDebugVariable(id.Name, t.Type)
+				}
 				if len(t.Values) != 0 {
 					for i, val := range t.Values {
 						ast.Walk(c, val)
@@ -320,6 +323,11 @@ func (c *codegen) Visit(node ast.Node) ast.Visitor {
 					c.convertToken(n.Tok)
 					l := c.scope.loadLocal(t.Name)
 					c.emitStoreLocal(l)
+				case token.DEFINE:
+					if !multiRet {
+						c.registerDebugVariable(t.Name, n.Rhs[i])
+					}
+					fallthrough
 				default:
 					if i == 0 || !multiRet {
 						ast.Walk(c, n.Rhs[i])
diff --git a/pkg/compiler/debug.go b/pkg/compiler/debug.go
index 101da8dbc..be1b96d92 100644
--- a/pkg/compiler/debug.go
+++ b/pkg/compiler/debug.go
@@ -104,6 +104,11 @@ func (c *codegen) emitDebugInfo() *DebugInfo {
 	return d
 }
 
+func (c *codegen) registerDebugVariable(name string, expr ast.Expr) {
+	typ := c.scTypeFromExpr(expr)
+	c.scope.variables = append(c.scope.variables, name+","+typ)
+}
+
 func (c *codegen) methodInfoFromScope(name string, scope *funcScope) *MethodDebugInfo {
 	ps := scope.decl.Type.Params
 	params := make([]DebugParam, 0, ps.NumFields())
@@ -122,6 +127,7 @@ func (c *codegen) methodInfoFromScope(name string, scope *funcScope) *MethodDebu
 		Parameters: params,
 		ReturnType: c.scReturnTypeFromScope(scope),
 		SeqPoints:  c.sequencePoints[name],
+		Variables:  scope.variables,
 	}
 }
 
diff --git a/pkg/compiler/debug_test.go b/pkg/compiler/debug_test.go
index 07bd2a517..baecbb09e 100644
--- a/pkg/compiler/debug_test.go
+++ b/pkg/compiler/debug_test.go
@@ -12,6 +12,8 @@ import (
 func TestCodeGen_DebugInfo(t *testing.T) {
 	src := `package foo
 func Main(op string) bool {
+	var s string
+	_ = s
 	res := methodInt(op)
 	_ = methodString()	
 	_ = methodByteArray()
@@ -56,6 +58,18 @@ func methodStruct() struct{} { return struct{}{} }
 		}
 	})
 
+	t.Run("variables", func(t *testing.T) {
+		vars := map[string][]string{
+			"Main": {"s,String", "res,Integer"},
+		}
+		for i := range d.Methods {
+			v, ok := vars[d.Methods[i].Name.Name]
+			if ok {
+				require.Equal(t, v, d.Methods[i].Variables)
+			}
+		}
+	})
+
 	// basic check that last instruction of every method is indeed RET
 	for i := range d.Methods {
 		index := d.Methods[i].Range.End
diff --git a/pkg/compiler/func_scope.go b/pkg/compiler/func_scope.go
index a43a0ec20..d4a0ca862 100644
--- a/pkg/compiler/func_scope.go
+++ b/pkg/compiler/func_scope.go
@@ -23,6 +23,8 @@ type funcScope struct {
 
 	// Range of opcodes corresponding to the function.
 	rng DebugRange
+	// Variables together with it's type in neo-vm.
+	variables []string
 
 	// Local variables
 	locals map[string]int
@@ -46,6 +48,7 @@ func newFuncScope(decl *ast.FuncDecl, label uint16) *funcScope {
 		label:     label,
 		locals:    map[string]int{},
 		voidCalls: map[*ast.CallExpr]bool{},
+		variables: []string{},
 		i:         -1,
 	}
 }