fix: handle dereference in proto2 bindings

Makefile

@@ -1,6 +1,6 @@
 .PHONY: test
 test:
-	cd testdata && make vendor
+	$(MAKE) -C testdata vendor
 	go test -v ./...
 
 .PHONY: install

processor.go

@@ -70,6 +70,23 @@ func (c *processor) process(n ast.Node) (*Result, error) {
 
 		c.processInner(x)
 
+	case *ast.StarExpr:
+		f, ok := x.X.(*ast.SelectorExpr)
+		if !ok {
+			return &Result{}, nil
+		}
+
+		if !isProtoMessage(c.info, f.X) {
+			return &Result{}, nil
+		}
+
+		// proto2 generates fields as pointers. Hence, the indirection
+		// must be removed when generating the fix for the case.
+		// The `*` is retained in `c.from`, but excluded from the fix
+		// present in the `c.to`.
+		c.writeFrom("*")
+		c.processInner(x.X)
+
 	default:
 		return nil, fmt.Errorf("not implemented for type: %s (%s)", reflect.TypeOf(x), formatNode(n))
 	}

protogetter.go

@@ -99,6 +99,7 @@ func Run(pass *analysis.Pass, cfg *Config) ([]Issue, error) {
 		(*ast.AssignStmt)(nil),
 		(*ast.CallExpr)(nil),
 		(*ast.SelectorExpr)(nil),
+		(*ast.StarExpr)(nil),
 		(*ast.IncDecStmt)(nil),
 		(*ast.UnaryExpr)(nil),
 	}

testdata/Makefile

@@ -17,4 +17,4 @@ protoc:
 		--go_opt paths=source_relative \
 		--go-grpc_out proto \
 		--go-grpc_opt paths=source_relative \
-		proto/test.proto
+		proto/test.proto proto/test_proto2.proto

testdata/proto/test_proto2.proto

@@ -0,0 +1,15 @@
+syntax = "proto2";
+
+option go_package = "github.com/ghostiam/protogetter/testdata/proto";
+
+message TestProto2 {
+  required double d = 1;
+  required float f = 2;
+  required int32 i32 = 3;
+  required int64 i64 = 4;
+  optional uint32 u32 = 5;
+  optional uint64 u64 = 6;
+  optional bool t = 7;
+  optional bytes b = 8;
+  optional string s = 9;
+}

testdata/test_proto2.go

@@ -0,0 +1,17 @@
+package testdata
+
+import (
+	"github.com/ghostiam/protogetter/testdata/proto"
+)
+
+func testInvalidProto2(t *proto.TestProto2) {
+	_ = *t.D   // want `avoid direct access to proto field \*t\.D, use t\.GetD\(\) instead`
+	_ = *t.F   // want `avoid direct access to proto field \*t\.F, use t\.GetF\(\) instead`
+	_ = *t.I32 // want `avoid direct access to proto field \*t\.I32, use t\.GetI32\(\) instead`
+	_ = *t.I64 // want `avoid direct access to proto field \*t\.I64, use t\.GetI64\(\) instead`
+	_ = *t.U32 // want `avoid direct access to proto field \*t\.U32, use t\.GetU32\(\) instead`
+	_ = *t.U64 // want `avoid direct access to proto field \*t\.U64, use t\.GetU64\(\) instead`
+	_ = *t.T   // want `avoid direct access to proto field \*t\.T, use t\.GetT\(\) instead`
+	_ = t.B    // want `avoid direct access to proto field t\.B, use t\.GetB\(\) instead`
+	_ = *t.S   // want `avoid direct access to proto field \*t\.S, use t\.GetS\(\) instead`
+}

testdata/test_proto2.go.golden

@@ -0,0 +1,17 @@
+package testdata
+
+import (
+	"github.com/ghostiam/protogetter/testdata/proto"
+)
+
+func testInvalidProto2(t *proto.TestProto2) {
+	_ = t.GetD()   // want `avoid direct access to proto field \*t\.D, use t\.GetD\(\) instead`
+	_ = t.GetF()   // want `avoid direct access to proto field \*t\.F, use t\.GetF\(\) instead`
+	_ = t.GetI32() // want `avoid direct access to proto field \*t\.I32, use t\.GetI32\(\) instead`
+	_ = t.GetI64() // want `avoid direct access to proto field \*t\.I64, use t\.GetI64\(\) instead`
+	_ = t.GetU32() // want `avoid direct access to proto field \*t\.U32, use t\.GetU32\(\) instead`
+	_ = t.GetU64() // want `avoid direct access to proto field \*t\.U64, use t\.GetU64\(\) instead`
+	_ = t.GetT()   // want `avoid direct access to proto field \*t\.T, use t\.GetT\(\) instead`
+	_ = t.GetB()   // want `avoid direct access to proto field t\.B, use t\.GetB\(\) instead`
+	_ = t.GetS()   // want `avoid direct access to proto field \*t\.S, use t\.GetS\(\) instead`
+}