From 2937a4c8bf376ead6ce6fbced773ba010b8f1dae Mon Sep 17 00:00:00 2001
From: Albert Le Batteux <contact@albttx.tech>
Date: Wed, 14 Jun 2023 14:43:38 +0100
Subject: [PATCH] feat: std.CurrentRealm

---
 .../p/demo/tests/subtests/subtests.gno        |  4 +-
 .../r/demo/tests/subtests/subtests.gno        |  4 +-
 gnovm/stdlibs/stdlibs.go                      | 38 +++++++++++++++++++
 gnovm/stdlibs/stdshim/stdshim.gno             |  8 ++++
 gnovm/tests/files/zrealm_crossrealm12.gno     | 37 ++++++++++++++++++
 5 files changed, 87 insertions(+), 4 deletions(-)
 create mode 100644 gnovm/tests/files/zrealm_crossrealm12.gno

diff --git a/examples/gno.land/p/demo/tests/subtests/subtests.gno b/examples/gno.land/p/demo/tests/subtests/subtests.gno
index cdff70380ec..e8796a73081 100644
--- a/examples/gno.land/p/demo/tests/subtests/subtests.gno
+++ b/examples/gno.land/p/demo/tests/subtests/subtests.gno
@@ -4,8 +4,8 @@ import (
 	"std"
 )
 
-func CurrentRealmPath() string {
-	return std.CurrentRealmPath()
+func GetCurrentRealm() std.Realm {
+	return std.CurrentRealm()
 }
 
 func GetPrevRealm() std.Realm {
diff --git a/examples/gno.land/r/demo/tests/subtests/subtests.gno b/examples/gno.land/r/demo/tests/subtests/subtests.gno
index cdff70380ec..e8796a73081 100644
--- a/examples/gno.land/r/demo/tests/subtests/subtests.gno
+++ b/examples/gno.land/r/demo/tests/subtests/subtests.gno
@@ -4,8 +4,8 @@ import (
 	"std"
 )
 
-func CurrentRealmPath() string {
-	return std.CurrentRealmPath()
+func GetCurrentRealm() std.Realm {
+	return std.CurrentRealm()
 }
 
 func GetPrevRealm() std.Realm {
diff --git a/gnovm/stdlibs/stdlibs.go b/gnovm/stdlibs/stdlibs.go
index 9ac790c2b4e..fb230a0cf86 100644
--- a/gnovm/stdlibs/stdlibs.go
+++ b/gnovm/stdlibs/stdlibs.go
@@ -263,6 +263,44 @@ func InjectPackage(store gno.Store, pn *gno.PackageNode) {
 				m.PushValue(res0)
 			},
 		)
+		pn.DefineNative("CurrentRealm",
+			gno.Flds( // params
+			),
+			gno.Flds( // results
+				"", "Realm",
+			),
+			func(m *gno.Machine) {
+				var (
+					ctx = m.Context.(ExecContext)
+					// Default lastCaller is OrigCaller, the signer of the tx
+					lastCaller  = ctx.OrigCaller
+					lastPkgPath = ""
+				)
+
+				for i := m.NumFrames() - 1; i > 0; i-- {
+					fr := m.Frames[i]
+					if fr.LastPackage != nil && fr.LastPackage.IsRealm() {
+						lastCaller = fr.LastPackage.GetPkgAddr().Bech32()
+						lastPkgPath = fr.LastPackage.PkgPath
+						break
+					}
+				}
+
+				// Return the result
+				res0 := gno.Go2GnoValue(
+					m.Alloc,
+					m.Store,
+					reflect.ValueOf(Realm{
+						addr:    lastCaller,
+						pkgPath: lastPkgPath,
+					}),
+				)
+
+				realmT := store.GetType(gno.DeclaredTypeID("std", "Realm"))
+				res0.T = realmT
+				m.PushValue(res0)
+			},
+		)
 		pn.DefineNative("PrevRealm",
 			gno.Flds( // params
 			),
diff --git a/gnovm/stdlibs/stdshim/stdshim.gno b/gnovm/stdlibs/stdshim/stdshim.gno
index 8e1fdc0da75..62e97088209 100644
--- a/gnovm/stdlibs/stdshim/stdshim.gno
+++ b/gnovm/stdlibs/stdshim/stdshim.gno
@@ -36,6 +36,14 @@ func GetOrigSend() Coins {
 	return Coins{}
 }
 
+func CurrentRealm() Realm {
+	panic(shimWarn)
+	return Realm{
+		addr:    Address(""),
+		pkgPath: "",
+	}
+}
+
 func PrevRealm() Realm {
 	panic(shimWarn)
 	return Realm{
diff --git a/gnovm/tests/files/zrealm_crossrealm12.gno b/gnovm/tests/files/zrealm_crossrealm12.gno
new file mode 100644
index 00000000000..ef8ea141ac5
--- /dev/null
+++ b/gnovm/tests/files/zrealm_crossrealm12.gno
@@ -0,0 +1,37 @@
+// PKGPATH: gno.land/r/crossrealm_test
+package crossrealm_test
+
+import (
+	"std"
+	"fmt"
+
+	psubtests "gno.land/p/demo/tests/subtests"
+	rsubtests "gno.land/r/demo/tests/subtests"
+)
+
+func main() {
+	tests := []struct{
+		fn func() std.Realm
+	}{
+		{ std.CurrentRealm },
+		{ psubtests.GetCurrentRealm },
+		{ rsubtests.GetCurrentRealm },
+	}
+	
+	for _, test := range tests {
+		r := test.fn()
+
+		if std.DerivePkgAddr(r.PkgPath()) != r.Addr() {
+			panic(fmt.Sprintf("ERROR: expected: %v, got: %v",
+				std.DerivePkgAddr(r.PkgPath()), r.Addr(),
+			))
+		}
+
+		println(r.PkgPath(), r.Addr())
+	}
+}
+
+// Output:
+// gno.land/r/crossrealm_test g1vla5mffzum6060t99u4xhm8mnhgxr0sz4k574p
+// gno.land/r/crossrealm_test g1vla5mffzum6060t99u4xhm8mnhgxr0sz4k574p
+// gno.land/r/demo/tests/subtests g13g48xnr7lzxsrvny0uf6lhx0cfaxy4n0n5geuf