Add Vat grab transformer

pkg/transformers/shared/constants.go

@@ -55,6 +55,7 @@ var (
 	pitFileIlkMethod          = "file(bytes32,bytes32,uint256)"
 	pitFileStabilityFeeMethod = GetSolidityMethodSignature(PitABI, "file")
 	tendMethod                = GetSolidityMethodSignature(FlipperABI, "tend")
+	vatGrabMethod             = GetSolidityMethodSignature(VatABI, "grab")
 	vatInitMethod             = GetSolidityMethodSignature(VatABI, "init")
 	vatTollMethod             = GetSolidityMethodSignature(VatABI, "toll")
 	vatTuneMethod             = GetSolidityMethodSignature(VatABI, "tune")
@@ -77,6 +78,7 @@ var (
 	PitFileIlkSignature          = GetLogNoteSignature(pitFileIlkMethod)
 	PitFileStabilityFeeSignature = GetLogNoteSignature(pitFileStabilityFeeMethod)
 	TendFunctionSignature        = GetLogNoteSignature(tendMethod)
+	VatGrabSignature             = GetLogNoteSignature(vatGrabMethod)
 	VatInitSignature             = GetLogNoteSignature(vatInitMethod)
 	VatTollSignature             = GetLogNoteSignature(vatTollMethod)
 	VatTuneSignature             = GetLogNoteSignature(vatTuneMethod)

pkg/transformers/shared/event_signature_generator_test.go

@@ -125,6 +125,13 @@ var _ = Describe("Event signature generator", func() {
 
 				Expect(expected).To(Equal(actual))
 			})
+
+			It("gets the vat grab method signature", func() {
+				expected := "grab(bytes32,bytes32,bytes32,bytes32,int256,int256)"
+				actual := shared.GetSolidityMethodSignature(shared.VatABI, "grab")
+
+				Expect(expected).To(Equal(actual))
+			})
 		})
 
 		Describe("it handles events", func() {