Add opcodes for dynamically indexing into Txn array fields

cmd/opdoc/opdoc.go

@@ -238,7 +238,7 @@ func argEnum(name string) []string {
 	if name == "global" {
 		return logic.GlobalFieldNames
 	}
-	if name == "txna" || name == "gtxna" || name == "gtxnsa" {
+	if name == "txna" || name == "gtxna" || name == "gtxnsa" || name == "txnas" || name == "gtxnas" {
 		return logic.TxnaFieldNames
 	}
 	if name == "asset_holding_get" {
@@ -282,7 +282,7 @@ func argEnumTypes(name string) string {
 	if name == "global" {
 		return typeString(logic.GlobalFieldTypes)
 	}
-	if name == "txna" || name == "gtxna" || name == "gtxnsa" {
+	if name == "txna" || name == "gtxna" || name == "gtxnsa" || name == "txnas" || name == "gtxnas" {
 		return typeString(logic.TxnaFieldTypes)
 	}
 	if name == "asset_holding_get" {

data/transactions/logic/README.md

@@ -221,6 +221,9 @@ Some of these have immediate data in the byte or bytes after the opcode.
 | `gloads i` | push Ith scratch space index of the Xth transaction in the current group |
 | `gaid t` | push the ID of the asset or application created in the Tth transaction of the current group |
 | `gaids` | push the ID of the asset or application created in the Xth transaction of the current group |
+| `txnas f` | pop an index A. push Ath value of the array field F of the current transaction |
+| `gtxnas t f` | pop an index A. push Ath value of the array field F from the Tth transaction in the current group |
+| `gtxnsas f` | pop an index A and an index B. push Bth value of the array field F from the Ath transaction in the current group |
 
 **Transaction Fields**
 

data/transactions/logic/TEAL_opcodes.md

@@ -1213,3 +1213,27 @@ bitlen interprets arrays as big-endian integers, unlike setbit/getbit
 - Mode: Application
 
 `log` can be called up to MaxLogCalls times in a program, and log up to a total of 1k bytes.
+
+## txnas f
+
+- Opcode: 0xc0 {uint8 transaction field index}
+- Pops: *... stack*, uint64
+- Pushes: any
+- pop an index A. push Ath value of the array field F of the current transaction
+- LogicSigVersion >= 5
+
+## gtxnas t f
+
+- Opcode: 0xc1 {uint8 transaction group index} {uint8 transaction field index}
+- Pops: *... stack*, uint64
+- Pushes: any
+- pop an index A. push Ath value of the array field F from the Tth transaction in the current group
+- LogicSigVersion >= 5
+
+## gtxnsas f
+
+- Opcode: 0xc2 {uint8 transaction field index}
+- Pops: *... stack*, {uint64 A}, {uint64 B}
+- Pushes: any
+- pop an index A and an index B. push Bth value of the array field F from the Ath transaction in the current group
+- LogicSigVersion >= 5

data/transactions/logic/assembler.go

@@ -816,7 +816,7 @@ func assembleTxn2(ops *OpStream, spec *OpSpec, args []string) error {
 
 func assembleTxna(ops *OpStream, spec *OpSpec, args []string) error {
 	if len(args) != 2 {
-		return ops.error("txna expects two arguments")
+		return ops.error("txna expects two immediate arguments")
 	}
 	fs, ok := txnFieldSpecByName[args[0]]
 	if !ok {
@@ -844,6 +844,28 @@ func assembleTxna(ops *OpStream, spec *OpSpec, args []string) error {
 	return nil
 }
 
+func assembleTxnas(ops *OpStream, spec *OpSpec, args []string) error {
+	if len(args) != 1 {
+		return ops.error("txnas expects one immediate argument")
+	}
+	fs, ok := txnFieldSpecByName[args[0]]
+	if !ok {
+		return ops.errorf("txnas unknown field: %#v", args[0])
+	}
+	_, ok = txnaFieldSpecByField[fs.field]
+	if !ok {
+		return ops.errorf("txnas unknown field: %#v", args[0])
+	}
+	if fs.version > ops.Version {
+		return ops.errorf("txnas %#v available in version %d. Missed #pragma version?", args[0], fs.version)
+	}
+
+	ops.pending.WriteByte(spec.Opcode)
+	ops.pending.WriteByte(uint8(fs.field))
+	ops.returns(fs.ftype)
+	return nil
+}
+
 func assembleGtxn(ops *OpStream, spec *OpSpec, args []string) error {
 	if len(args) != 2 {
 		return ops.error("gtxn expects two arguments")
@@ -925,6 +947,38 @@ func assembleGtxna(ops *OpStream, spec *OpSpec, args []string) error {
 	return nil
 }
 
+func assembleGtxnas(ops *OpStream, spec *OpSpec, args []string) error {
+	if len(args) != 2 {
+		return ops.error("gtxnas expects two immediate arguments")
+	}
+
+	slot, err := strconv.ParseUint(args[0], 0, 64)
+	if err != nil {
+		return ops.error(err)
+	}
+	if slot > 255 {
+		return ops.errorf("gtxnas group index beyond 255: %d", slot)
+	}
+
+	fs, ok := txnFieldSpecByName[args[1]]
+	if !ok {
+		return ops.errorf("gtxnas unknown field: %#v", args[1])
+	}
+	_, ok = txnaFieldSpecByField[fs.field]
+	if !ok {
+		return ops.errorf("gtxnas unknown field: %#v", args[1])
+	}
+	if fs.version > ops.Version {
+		return ops.errorf("gtxnas %#v available in version %d. Missed #pragma version?", args[1], fs.version)
+	}
+
+	ops.pending.WriteByte(spec.Opcode)
+	ops.pending.WriteByte(uint8(slot))
+	ops.pending.WriteByte(uint8(fs.field))
+	ops.returns(fs.ftype)
+	return nil
+}
+
 func assembleGtxns(ops *OpStream, spec *OpSpec, args []string) error {
 	if len(args) == 2 {
 		gtxnsa := OpsByName[ops.Version]["gtxnsa"]
@@ -980,6 +1034,27 @@ func assembleGtxnsa(ops *OpStream, spec *OpSpec, args []string) error {
 	return nil
 }
 
+func assembleGtxnsas(ops *OpStream, spec *OpSpec, args []string) error {
+	if len(args) != 1 {
+		return ops.error("gtxnsas expects one immediate argument")
+	}
+	fs, ok := txnFieldSpecByName[args[0]]
+	if !ok {
+		return ops.errorf("gtxnsas unknown field: %#v", args[0])
+	}
+	_, ok = txnaFieldSpecByField[fs.field]
+	if !ok {
+		return ops.errorf("gtxnsas unknown field: %#v", args[0])
+	}
+	if fs.version > ops.Version {
+		return ops.errorf("gtxnsas %#v available in version %d. Missed #pragma version?", args[0], fs.version)
+	}
+	ops.pending.WriteByte(spec.Opcode)
+	ops.pending.WriteByte(uint8(fs.field))
+	ops.returns(fs.ftype)
+	return nil
+}
+
 func assembleGlobal(ops *OpStream, spec *OpSpec, args []string) error {
 	if len(args) != 1 {
 		return ops.errorf("%s expects one argument", spec.Name)
@@ -2294,7 +2369,7 @@ func checkPushBytes(cx *evalContext) error {
 	return cx.err
 }
 
-// This is also used to disassemble gtxns
+// This is also used to disassemble gtxns, gtxnsas and txnas
 func disTxn(dis *disassembleState, spec *OpSpec) (string, error) {
 	lastIdx := dis.pc + 1
 	if len(dis.program) <= lastIdx {
@@ -2325,6 +2400,7 @@ func disTxna(dis *disassembleState, spec *OpSpec) (string, error) {
 	return fmt.Sprintf("%s %s %d", spec.Name, TxnFieldNames[txarg], arrayFieldIdx), nil
 }
 
+// This is also used to disassemble gtxnas
 func disGtxn(dis *disassembleState, spec *OpSpec) (string, error) {
 	lastIdx := dis.pc + 2
 	if len(dis.program) <= lastIdx {
@@ -2337,7 +2413,7 @@ func disGtxn(dis *disassembleState, spec *OpSpec) (string, error) {
 	if int(txarg) >= len(TxnFieldNames) {
 		return "", fmt.Errorf("invalid txn arg index %d at pc=%d", txarg, dis.pc)
 	}
-	return fmt.Sprintf("gtxn %d %s", gi, TxnFieldNames[txarg]), nil
+	return fmt.Sprintf("%s %d %s", spec.Name, gi, TxnFieldNames[txarg]), nil
 }
 
 func disGtxna(dis *disassembleState, spec *OpSpec) (string, error) {

data/transactions/logic/assembler_test.go

@@ -312,6 +312,13 @@ extract16bits
 log
 txn Nonparticipation
 gtxn 0 Nonparticipation
+int 1
+txnas ApplicationArgs
+int 0
+gtxnas 0 ApplicationArgs
+int 0
+int 0
+gtxnsas ApplicationArgs
 `
 
 var nonsense = map[uint64]string{
@@ -327,7 +334,7 @@ var compiled = map[uint64]string{
 	2: "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",
 	3: "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",
 	4: "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",
-	5: "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",
+	5: "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",
 }
 
 func pseudoOp(opcode string) bool {
@@ -494,13 +501,15 @@ func TestAssembleTxna(t *testing.T) {
 	testLine(t, "gtxna 0 Sender 256", AssemblerMaxVersion, "gtxna unknown field: \"Sender\"")
 	testLine(t, "txn Accounts 0", 1, "txn expects one argument")
 	testLine(t, "txn Accounts 0 1", 2, "txn expects one or two arguments")
-	testLine(t, "txna Accounts 0 1", AssemblerMaxVersion, "txna expects two arguments")
+	testLine(t, "txna Accounts 0 1", AssemblerMaxVersion, "txna expects two immediate arguments")
+	testLine(t, "txnas Accounts 1", AssemblerMaxVersion, "txnas expects one immediate argument")
 	testLine(t, "txna Accounts a", AssemblerMaxVersion, "strconv.ParseUint...")
 	testLine(t, "gtxn 0 Sender 0", 1, "gtxn expects two arguments")
 	testLine(t, "gtxn 0 Sender 1 2", 2, "gtxn expects two or three arguments")
 	testLine(t, "gtxna 0 Accounts 1 2", AssemblerMaxVersion, "gtxna expects three arguments")
 	testLine(t, "gtxna a Accounts 0", AssemblerMaxVersion, "strconv.ParseUint...")
 	testLine(t, "gtxna 0 Accounts a", AssemblerMaxVersion, "strconv.ParseUint...")
+	testLine(t, "gtxnas Accounts 1 2", AssemblerMaxVersion, "gtxnas expects two immediate arguments")
 	testLine(t, "txn ABC", 2, "txn unknown field: \"ABC\"")
 	testLine(t, "gtxn 0 ABC", 2, "gtxn unknown field: \"ABC\"")
 	testLine(t, "gtxn a ABC", 2, "strconv.ParseUint...")

data/transactions/logic/doc.go

@@ -152,6 +152,10 @@ var opDocByName = map[string]string{
 	"b~":  "X with all bits inverted",
 
 	"log": "write bytes to log state of the current application",
+
+	"txnas":   "pop an index A. push Ath value of the array field F of the current transaction",
+	"gtxnas":  "pop an index A. push Ath value of the array field F from the Tth transaction in the current group",
+	"gtxnsas": "pop an index A and an index B. push Bth value of the array field F from the Ath transaction in the current group",
 }
 
 // OpDoc returns a description of the op
@@ -191,6 +195,9 @@ var opcodeImmediateNotes = map[string]string{
 	"asset_holding_get": "{uint8 asset holding field index}",
 	"asset_params_get":  "{uint8 asset params field index}",
 	"app_params_get":    "{uint8 app params field index}",
+	"txnas":             "{uint8 transaction field index}",
+	"gtxnas":            "{uint8 transaction group index} {uint8 transaction field index}",
+	"gtxnsas":           "{uint8 transaction field index}",
 }
 
 // OpImmediateNote returns a short string about immediate data which follows the op byte
@@ -252,7 +259,7 @@ var OpGroups = map[string][]string{
 	"Byte Array Slicing":   {"substring", "substring3", "extract", "extract3", "extract16bits", "extract32bits", "extract64bits"},
 	"Byteslice Arithmetic": {"b+", "b-", "b/", "b*", "b<", "b>", "b<=", "b>=", "b==", "b!=", "b%"},
 	"Byteslice Logic":      {"b|", "b&", "b^", "b~"},
-	"Loading Values":       {"intcblock", "intc", "intc_0", "intc_1", "intc_2", "intc_3", "pushint", "bytecblock", "bytec", "bytec_0", "bytec_1", "bytec_2", "bytec_3", "pushbytes", "bzero", "arg", "arg_0", "arg_1", "arg_2", "arg_3", "txn", "gtxn", "txna", "gtxna", "gtxns", "gtxnsa", "global", "load", "store", "gload", "gloads", "gaid", "gaids"},
+	"Loading Values":       {"intcblock", "intc", "intc_0", "intc_1", "intc_2", "intc_3", "pushint", "bytecblock", "bytec", "bytec_0", "bytec_1", "bytec_2", "bytec_3", "pushbytes", "bzero", "arg", "arg_0", "arg_1", "arg_2", "arg_3", "txn", "gtxn", "txna", "gtxna", "gtxns", "gtxnsa", "global", "load", "store", "gload", "gloads", "gaid", "gaids", "txnas", "gtxnas", "gtxnsas"},
 	"Flow Control":         {"err", "bnz", "bz", "b", "return", "pop", "dup", "dup2", "dig", "cover", "uncover", "swap", "select", "assert", "callsub", "retsub"},
 	"State Access":         {"balance", "min_balance", "app_opted_in", "app_local_get", "app_local_get_ex", "app_global_get", "app_global_get_ex", "app_local_put", "app_global_put", "app_local_del", "app_global_del", "asset_holding_get", "asset_params_get", "app_params_get", "log"},
 }

data/transactions/logic/eval.go

@@ -2062,6 +2062,29 @@ func opTxna(cx *evalContext) {
 	cx.stack = append(cx.stack, sv)
 }
 
+func opTxnas(cx *evalContext) {
+	last := len(cx.stack) - 1
+
+	field := TxnField(uint64(cx.program[cx.pc+1]))
+	fs, ok := txnFieldSpecByField[field]
+	if !ok || fs.version > cx.version {
+		cx.err = fmt.Errorf("invalid txn field %d", field)
+		return
+	}
+	_, ok = txnaFieldSpecByField[field]
+	if !ok {
+		cx.err = fmt.Errorf("txnas unsupported field %d", field)
+		return
+	}
+	arrayFieldIdx := cx.stack[last].Uint
+	sv, err := cx.txnFieldToStack(&cx.Txn.Txn, field, arrayFieldIdx, cx.GroupIndex)
+	if err != nil {
+		cx.err = err
+		return
+	}
+	cx.stack[last] = sv
+}
+
 func opGtxn(cx *evalContext) {
 	gtxid := int(uint(cx.program[cx.pc+1]))
 	if gtxid >= len(cx.TxnGroup) {
@@ -2122,6 +2145,35 @@ func opGtxna(cx *evalContext) {
 	cx.stack = append(cx.stack, sv)
 }
 
+func opGtxnas(cx *evalContext) {
+	last := len(cx.stack) - 1
+
+	gtxid := int(uint(cx.program[cx.pc+1]))
+	if gtxid >= len(cx.TxnGroup) {
+		cx.err = fmt.Errorf("gtxnas lookup TxnGroup[%d] but it only has %d", gtxid, len(cx.TxnGroup))
+		return
+	}
+	tx := &cx.TxnGroup[gtxid].Txn
+	field := TxnField(uint64(cx.program[cx.pc+2]))
+	fs, ok := txnFieldSpecByField[field]
+	if !ok || fs.version > cx.version {
+		cx.err = fmt.Errorf("invalid txn field %d", field)
+		return
+	}
+	_, ok = txnaFieldSpecByField[field]
+	if !ok {
+		cx.err = fmt.Errorf("gtxnas unsupported field %d", field)
+		return
+	}
+	arrayFieldIdx := cx.stack[last].Uint
+	sv, err := cx.txnFieldToStack(tx, field, arrayFieldIdx, gtxid)
+	if err != nil {
+		cx.err = err
+		return
+	}
+	cx.stack[last] = sv
+}
+
 func opGtxns(cx *evalContext) {
 	last := len(cx.stack) - 1
 	gtxid := int(cx.stack[last].Uint)
@@ -2184,6 +2236,37 @@ func opGtxnsa(cx *evalContext) {
 	cx.stack[last] = sv
 }
 
+func opGtxnsas(cx *evalContext) {
+	last := len(cx.stack) - 1
+	prev := last - 1
+
+	gtxid := int(cx.stack[prev].Uint)
+	if gtxid >= len(cx.TxnGroup) {
+		cx.err = fmt.Errorf("gtxnsa lookup TxnGroup[%d] but it only has %d", gtxid, len(cx.TxnGroup))
+		return
+	}
+	tx := &cx.TxnGroup[gtxid].Txn
+	field := TxnField(uint64(cx.program[cx.pc+1]))
+	fs, ok := txnFieldSpecByField[field]
+	if !ok || fs.version > cx.version {
+		cx.err = fmt.Errorf("invalid txn field %d", field)
+		return
+	}
+	_, ok = txnaFieldSpecByField[field]
+	if !ok {
+		cx.err = fmt.Errorf("gtxnsa unsupported field %d", field)
+		return
+	}
+	arrayFieldIdx := cx.stack[last].Uint
+	sv, err := cx.txnFieldToStack(tx, field, arrayFieldIdx, gtxid)
+	if err != nil {
+		cx.err = err
+		return
+	}
+	cx.stack[prev] = sv
+	cx.stack = cx.stack[:last]
+}
+
 func opGaidImpl(cx *evalContext, groupIdx int, opName string) (sv stackValue, err error) {
 	if groupIdx >= len(cx.TxnGroup) {
 		err = fmt.Errorf("%s lookup TxnGroup[%d] but it only has %d", opName, groupIdx, len(cx.TxnGroup))

data/transactions/logic/evalStateful_test.go

@@ -2843,6 +2843,9 @@ func TestReturnTypes(t *testing.T) {
 		"pushbytes":         `pushbytes "jojogoodgorilla"`,
 		"app_params_get":    "app_params_get AppGlobalNumUint",
 		"extract":           "extract 0 2",
+		"txnas":             "txnas ApplicationArgs",
+		"gtxnas":            "gtxnas 0 ApplicationArgs",
+		"gtxnsas":           "pop; pop; int 0; int 0; gtxnsas ApplicationArgs",
 	}
 
 	byName := OpsByName[LogicVersion]