From ca06b3fadd763c1a36b8a420f8d8b27f96ce118a Mon Sep 17 00:00:00 2001
From: Runtian Zhou <runtian@aptoslabs.com>
Date: Wed, 22 Mar 2023 15:33:42 -0700
Subject: [PATCH] fixup! Add interface example

---
 .../example/coin_interface/coin_interface.exp |   2 +-
 .../coin_interface/coin_interface.mvir        | 120 +++++++++++++++++-
 2 files changed, 117 insertions(+), 5 deletions(-)

diff --git a/language/move-vm/transactional-tests/tests/function_pointers/example/coin_interface/coin_interface.exp b/language/move-vm/transactional-tests/tests/function_pointers/example/coin_interface/coin_interface.exp
index b134af1aea..f33e2b18fc 100644
--- a/language/move-vm/transactional-tests/tests/function_pointers/example/coin_interface/coin_interface.exp
+++ b/language/move-vm/transactional-tests/tests/function_pointers/example/coin_interface/coin_interface.exp
@@ -1 +1 @@
-processed 5 tasks
+processed 8 tasks
diff --git a/language/move-vm/transactional-tests/tests/function_pointers/example/coin_interface/coin_interface.mvir b/language/move-vm/transactional-tests/tests/function_pointers/example/coin_interface/coin_interface.mvir
index 47fd5137c1..41336c5ca7 100644
--- a/language/move-vm/transactional-tests/tests/function_pointers/example/coin_interface/coin_interface.mvir
+++ b/language/move-vm/transactional-tests/tests/function_pointers/example/coin_interface/coin_interface.mvir
@@ -25,6 +25,24 @@ module 0x42.CoinInterface {
     label b0:
         return *&move(self).T<T>::merge;
     }
+
+    public value<T>(self: &Self.T<T>, coin: &T): u64 {
+        let value: |&T| (u64);
+        let ret: u64;
+    label b0:
+        value = *&move(self).T<T>::value;
+        ret = call_function_pointer<|&T| (u64)>(move(coin), move(value));
+        return move(ret);
+    }
+
+    public split<T>(self: &Self.T<T>, coin: &mut T, amount: u64): T {
+        let split: |&mut T, u64| (T);
+        let ret: T;
+    label b0:
+        split = *&move(self).T<T>::split;
+        ret = call_function_pointer<|&mut T, u64| (T)>(move(coin), move(amount), move(split));
+        return move(ret);
+    }
 }
 
 //# publish
@@ -80,6 +98,59 @@ module 0x42.BasicCoin1 {
     }
 }
 
+
+//# publish
+module 0x42.BasicCoin2 {
+    import 0x42.CoinInterface;
+
+    struct Coin has store, drop { value: u64 }
+
+    public zero(): Self.Coin {
+    label b0:
+        return Coin { value: 0 };
+    }
+
+    public mint(value: u64): Self.Coin {
+    label b0:
+        return Coin { value: move(value) };
+    }
+
+    public value(c: &Self.Coin): u64 {
+    label b0:
+        return *&move(c).Coin::value;
+    }
+
+    public merge(c: &mut Self.Coin, other: Self.Coin) {
+        let value: u64;
+    label b0:
+        Coin { value } = move(other);
+        *&mut move(c).Coin::value = (*&copy(c).Coin::value) + 1;
+        return;
+    }
+
+
+    public split(c: &mut Self.Coin, value: u64): Self.Coin {
+        let coin_value: u64;
+    label b0:
+        coin_value = *&copy(c).Coin::value;
+        assert(copy(coin_value) >= copy(value), 0);
+        *&mut copy(c).Coin::value = move(coin_value) - copy(value);
+        return Coin { value: move(value) };
+    }
+
+    public coin_interface(): CoinInterface.T<Self.Coin> {
+        let value: |&Self.Coin| (u64);
+        let split: |&mut Self.Coin, u64| (Self.Coin);
+        let merge: |&mut Self.Coin, Self.Coin| ();
+        let interface: CoinInterface.T<Self.Coin>;
+    label b0:
+        value = get_function_pointer(Self.value);
+        split = get_function_pointer(Self.split);
+        merge = get_function_pointer(Self.merge);
+        interface = CoinInterface.new_interface<Self.Coin>(move(value), move(split), move(merge));
+        return move(interface);
+    }
+}
 //# publish
 module 0x42.CoinType {
     struct Foo has drop {
@@ -91,13 +162,11 @@ module 0x42.CoinType {
 module 0x42.GenericAdder {
     import 0x42.CoinInterface;
     public add_coins<T>(interface: &CoinInterface.T<T>, coin1: &T, coin2: &T): u64 {
-        let value: |&T| (u64);
         let v1: u64;
         let v2: u64;
     label b0:
-        value = CoinInterface.value_func<T>(move(interface));
-        v1 = call_function_pointer<|&T| (u64)>(move(coin1), copy(value));
-        v2 = call_function_pointer<|&T| (u64)>(move(coin2), copy(value));
+        v1 = CoinInterface.value<T>(copy(interface), move(coin1));
+        v2 = CoinInterface.value<T>(move(interface), move(coin2));
         return move(v1) + move(v2);
     }
 }
@@ -123,3 +192,46 @@ label b0:
     return;
 }
 
+//# run
+import 0x42.CoinInterface;
+import 0x42.BasicCoin2;
+import 0x42.GenericAdder;
+
+main() {
+    let interface: CoinInterface.T<BasicCoin2.Coin>;
+    let coin1: BasicCoin2.Coin;
+    let coin2: BasicCoin2.Coin;
+    let v: u64;
+label b0:
+    coin1 = BasicCoin2.mint(10);
+    coin2 = BasicCoin2.mint(20);
+    interface = BasicCoin2.coin_interface();
+
+    v = GenericAdder.add_coins<BasicCoin2.Coin>(&interface, &coin1, &coin2);
+    assert(move(v) == 30, 0);
+    return;
+}
+
+
+
+//# run
+import 0x42.CoinInterface;
+import 0x42.BasicCoin2;
+import 0x42.GenericAdder;
+
+main() {
+    let interface: CoinInterface.T<BasicCoin2.Coin>;
+    let coin1: BasicCoin2.Coin;
+    let coin2: BasicCoin2.Coin;
+    let v: u64;
+label b0:
+    coin1 = BasicCoin2.mint(10);
+    interface = BasicCoin2.coin_interface();
+
+    coin2 = CoinInterface.split<BasicCoin2.Coin>(&interface, &mut coin1, 5);
+    v = BasicCoin2.value(&coin2);
+
+    assert(move(v) == 5, 0);
+    return;
+}
+