Add account[addr].assetBalance() test

GUIDE.md

@@ -207,6 +207,13 @@ There are 9 builtin objects:
 
 Starting with TEAL v5 assets and apps can be specified by both index and absolute value (but must appear in `ForeignApps`/ `ForeignAssets`).
 The same rule is applicable to account addresses - it can be either an index or an address (but must appear in `Accounts`).
+For example, to obtain an _application account_ balance (of asset balance), one can write
+```
+let asset = 100;
+let appAddr = global.CurrentApplicationAddress
+let balance, ok = accounts[appAddr].acctBalance()
+let amount, exist = accounts[appAddr].assetBalance(asset);
+```
 
 #### Transaction fields
 

compiler/codegen_test.go

@@ -927,6 +927,7 @@ function approval() {
 	let asset = 100;
 	let acc = 1;
 	let amount, exist = accounts[acc].assetBalance(asset);
+	amount, exist = accounts[global.CurrentApplicationAddress].assetBalance(asset);
 	return exist;
 }
 `
@@ -946,6 +947,11 @@ load 0
 asset_holding_get AssetBalance
 store 2
 store 3
+global CurrentApplicationAddress
+load 0
+asset_holding_get AssetBalance
+store 2
+store 3
 load 2
 return
 end_main:

test/misc_test.go

@@ -2,6 +2,8 @@ package test
 
 import (
 	"testing"
+
+	"github.com/stretchr/testify/require"
 )
 
 func TestByteArith(t *testing.T) {
@@ -72,3 +74,17 @@ function logic() {
 `
 	performTest(t, source)
 }
+
+func TestAppAddress(t *testing.T) {
+	source := `
+function approval() {
+	let asset = 100;
+	let acc = 1;
+	let amount, exist = accounts[acc].assetBalance(asset);
+	amount, exist = accounts[global.CurrentApplicationAddress].assetBalance(asset);
+	return exist;
+}
+`
+	ops := compileTest(t, source)
+	require.NotEmpty(t, ops.Program)
+}

test/tuple_test.go

@@ -1,43 +1,9 @@
 package test
 
 import (
-	"fmt"
-	"strings"
 	"testing"
-
-	"github.com/algorand/go-algorand/data/transactions/logic"
-	"github.com/stretchr/testify/require"
-
-	"github.com/pzbitskiy/tealang/compiler"
-	"github.com/pzbitskiy/tealang/dryrun"
 )
 
-func compileTest(t *testing.T, source string) *logic.OpStream {
-	t.Helper()
-	a := require.New(t)
-	result, errors := compiler.Parse(source)
-	a.NotEmpty(result, errors)
-	a.Empty(errors)
-
-	teal := compiler.Codegen(result)
-	op, err := logic.AssembleString(teal)
-	a.NoError(err)
-	return op
-}
-
-func performTest(t *testing.T, source string) {
-	t.Helper()
-	a := require.New(t)
-	op := compileTest(t, source)
-
-	sb := strings.Builder{}
-	pass, err := dryrun.Run(op.Program, "", &sb)
-	fmt.Printf("trace:\n%s\n", sb.String())
-
-	a.NoError(err)
-	a.True(pass)
-}
-
 func TestAddw(t *testing.T) {
 	source := `
 function logic() {

test/util.go

@@ -0,0 +1,38 @@
+package test
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/algorand/go-algorand/data/transactions/logic"
+	"github.com/pzbitskiy/tealang/compiler"
+	"github.com/pzbitskiy/tealang/dryrun"
+	"github.com/stretchr/testify/require"
+)
+
+func compileTest(t *testing.T, source string) *logic.OpStream {
+	t.Helper()
+	a := require.New(t)
+	result, errors := compiler.Parse(source)
+	a.NotEmpty(result, errors)
+	a.Empty(errors)
+
+	teal := compiler.Codegen(result)
+	op, err := logic.AssembleString(teal)
+	a.NoError(err)
+	return op
+}
+
+func performTest(t *testing.T, source string) {
+	t.Helper()
+	a := require.New(t)
+	op := compileTest(t, source)
+
+	sb := strings.Builder{}
+	pass, err := dryrun.Run(op.Program, "", &sb)
+	fmt.Printf("trace:\n%s\n", sb.String())
+
+	a.NoError(err)
+	a.True(pass)
+}