fix: handle single item tuples correctly

examples/sizes.txt

@@ -93,7 +93,7 @@
   too_many_permutations                            112       106      6       106      0 
   transaction/Transaction                          996       932     64       932      0 
   tuple_support/TupleComparisons                   136        75     61        75      0 
-  tuple_support/TupleSupport                       632       406    226       406      0 
+  tuple_support/TupleSupport                       643       413    230       413      0 
   typed_abi_call/Greeter                          2861      2446    415      2446      0 
   typed_abi_call/Logger                            896       762    134       762      0 
   unary/Unary                                      136        96     40        96      0 

src/puya/ir/builder/main.py

@@ -329,6 +329,13 @@ def visit_checked_maybe(self, expr: awst_nodes.CheckedMaybe) -> TExpression:
         return value
 
     def visit_var_expression(self, expr: awst_nodes.VarExpression) -> TExpression:
+        # TODO: remove this once wtypes are available at IR layer and assign can deal with
+        #       single item tuples correctly
+        if isinstance(expr.wtype, wtypes.WTuple) and len(expr.wtype.types) == 1:
+            ir_type = wtype_to_ir_type(expr.wtype.types[0])
+            return self.context.ssa.read_variable(
+                expr.name, ir_type, self.context.block_builder.active_block
+            )
         if isinstance(expr.wtype, wtypes.WTuple):
             return ValueTuple(
                 source_location=expr.source_location,

test_cases/tuple_support/out/TupleSupport.approval.teal

@@ -135,19 +135,22 @@ main_entrypoint@2:
     byte "not empty2"
     log
     // tuple_support/tuple_support.py:59
+    // single_tuple()
+    callsub single_tuple
+    // tuple_support/tuple_support.py:60
     // return a + b
     int 3
     return
 
 
 // test_cases.tuple_support.tuple_support.add_three_values(values.0: uint64, values.1: uint64, values.2: uint64) -> uint64:
 add_three_values:
-    // tuple_support/tuple_support.py:121-122
+    // tuple_support/tuple_support.py:128-129
     // @subroutine
     // def add_three_values(values: tuple[UInt64, UInt64, UInt64]) -> UInt64:
     proto 3 1
     byte ""
-    // tuple_support/tuple_support.py:123
+    // tuple_support/tuple_support.py:130
     // total = UInt64(0)
     int 0
     frame_dig -3
@@ -164,7 +167,7 @@ add_three_values_for_header_2@3:
     frame_dig 0
 
 add_three_values_for_body@4:
-    // tuple_support/tuple_support.py:125
+    // tuple_support/tuple_support.py:132
     // total += value
     frame_dig 1
     uncover 2
@@ -176,62 +179,62 @@ add_three_values_for_body@4:
     int 1
     +
     frame_bury 0
-    // tuple_support/tuple_support.py:124
+    // tuple_support/tuple_support.py:131
     // for value in values:
     switch add_three_values_for_header_1@2 add_three_values_for_header_2@3
-    // tuple_support/tuple_support.py:127
+    // tuple_support/tuple_support.py:134
     // return total
     frame_bury 0
     retsub
 
 
 // test_cases.tuple_support.tuple_support.bytes_combine(arg.0: bytes, arg.1: bytes) -> bytes:
 bytes_combine:
-    // tuple_support/tuple_support.py:105-106
+    // tuple_support/tuple_support.py:112-113
     // @subroutine
     // def bytes_combine(arg: tuple[Bytes, Bytes]) -> Bytes:
     proto 2 1
-    // tuple_support/tuple_support.py:108
+    // tuple_support/tuple_support.py:115
     // result = a + b
     frame_dig -2
     frame_dig -1
     concat
-    // tuple_support/tuple_support.py:109
+    // tuple_support/tuple_support.py:116
     // return result
     retsub
 
 
 // test_cases.tuple_support.tuple_support.addw2(a.0: uint64, a.1: uint64, b.0: uint64, b.1: uint64) -> uint64, uint64, uint64:
 addw2:
-    // tuple_support/tuple_support.py:130-131
+    // tuple_support/tuple_support.py:137-138
     // @subroutine
     // def addw2(a: tuple[UInt64, UInt64], b: tuple[UInt64, UInt64]) -> tuple[UInt64, UInt64, UInt64]:
     proto 4 3
-    // tuple_support/tuple_support.py:134
+    // tuple_support/tuple_support.py:141
     // lo_carry, c_lo = op.addw(a_lo, b_lo)
     frame_dig -3
     frame_dig -1
     addw
     swap
-    // tuple_support/tuple_support.py:135
+    // tuple_support/tuple_support.py:142
     // hi_carry1, c_mid = op.addw(a_hi, b_hi)
     frame_dig -4
     frame_dig -2
     addw
-    // tuple_support/tuple_support.py:136
+    // tuple_support/tuple_support.py:143
     // hi_carry2, c_mid = op.addw(c_mid, lo_carry)
     uncover 2
     addw
     cover 2
-    // tuple_support/tuple_support.py:137
+    // tuple_support/tuple_support.py:144
     // did_overflow, c_hi = op.addw(hi_carry1, hi_carry2)
     addw
     swap
-    // tuple_support/tuple_support.py:138
+    // tuple_support/tuple_support.py:145
     // assert not did_overflow, "is such a thing even possible? 👽"
     !
     assert // is such a thing even possible? 👽
-    // tuple_support/tuple_support.py:139
+    // tuple_support/tuple_support.py:146
     // return c_hi, c_mid, c_lo
     swap
     uncover 2
@@ -240,31 +243,31 @@ addw2:
 
 // test_cases.tuple_support.tuple_support.bytes_multiply(arg.0: bytes, arg.1: uint64) -> bytes:
 bytes_multiply:
-    // tuple_support/tuple_support.py:112-113
+    // tuple_support/tuple_support.py:119-120
     // @subroutine
     // def bytes_multiply(arg: tuple[Bytes, UInt64]) -> Bytes:
     proto 2 1
-    // tuple_support/tuple_support.py:115
+    // tuple_support/tuple_support.py:122
     // result = Bytes()
     byte 0x
-    // tuple_support/tuple_support.py:116
+    // tuple_support/tuple_support.py:123
     // for _i in urange(count):
     int 0
 
 bytes_multiply_for_header@1:
-    // tuple_support/tuple_support.py:116
+    // tuple_support/tuple_support.py:123
     // for _i in urange(count):
     frame_dig 1
     frame_dig -1
     <
     bz bytes_multiply_after_for@5
-    // tuple_support/tuple_support.py:117
+    // tuple_support/tuple_support.py:124
     // result += b
     frame_dig 0
     frame_dig -2
     concat
     frame_bury 0
-    // tuple_support/tuple_support.py:116
+    // tuple_support/tuple_support.py:123
     // for _i in urange(count):
     frame_dig 1
     int 1
@@ -273,33 +276,33 @@ bytes_multiply_for_header@1:
     b bytes_multiply_for_header@1
 
 bytes_multiply_after_for@5:
-    // tuple_support/tuple_support.py:118
+    // tuple_support/tuple_support.py:125
     // return result
     retsub
 
 
 // test_cases.tuple_support.tuple_support.test_tuple_swap(zero: uint64) -> void:
 test_tuple_swap:
-    // tuple_support/tuple_support.py:142-143
+    // tuple_support/tuple_support.py:149-150
     // @subroutine
     // def test_tuple_swap(zero: UInt64) -> None:
     proto 1 0
-    // tuple_support/tuple_support.py:144
+    // tuple_support/tuple_support.py:151
     // a = zero + 1
     frame_dig -1
     int 1
     +
-    // tuple_support/tuple_support.py:145
+    // tuple_support/tuple_support.py:152
     // b = zero + 2
     frame_dig -1
     int 2
     +
-    // tuple_support/tuple_support.py:147
+    // tuple_support/tuple_support.py:154
     // assert a == 2, "a should be two"
     int 2
     ==
     assert // a should be two
-    // tuple_support/tuple_support.py:148
+    // tuple_support/tuple_support.py:155
     // assert b == 1, "b should be one"
     int 1
     ==
@@ -309,11 +312,11 @@ test_tuple_swap:
 
 // test_cases.tuple_support.tuple_support.slicing(values.0: uint64, values.1: uint64, values.2: uint64, values.3: uint64, values.4: uint64, values.5: uint64, values.6: uint64, values.7: uint64) -> void:
 slicing:
-    // tuple_support/tuple_support.py:151-152
+    // tuple_support/tuple_support.py:158-159
     // @subroutine
     // def slicing(values: tuple[UInt64, UInt64, UInt64, UInt64, UInt64, UInt64, UInt64, UInt64]) -> None:
     proto 8 0
-    // tuple_support/tuple_support.py:154
+    // tuple_support/tuple_support.py:161
     // assert add_three_values(one_to_three) == values[0] + values[1] + values[2]
     frame_dig -8
     frame_dig -7
@@ -331,7 +334,7 @@ slicing:
 
 // test_cases.tuple_support.tuple_support.bin_ops() -> void:
 bin_ops:
-    // tuple_support/tuple_support.py:77-78
+    // tuple_support/tuple_support.py:84-85
     // @subroutine
     // def bin_ops() -> None:
     proto 0 0
@@ -340,15 +343,15 @@ bin_ops:
 
 // test_cases.tuple_support.tuple_support.non_empty_tuple() -> uint64, uint64:
 non_empty_tuple:
-    // tuple_support/tuple_support.py:71-72
+    // tuple_support/tuple_support.py:78-79
     // @subroutine
     // def non_empty_tuple() -> tuple[UInt64, UInt64]:
     proto 0 2
-    // tuple_support/tuple_support.py:73
+    // tuple_support/tuple_support.py:80
     // log("non_empty_tuple called")
     byte "non_empty_tuple called"
     log
-    // tuple_support/tuple_support.py:74
+    // tuple_support/tuple_support.py:81
     // return UInt64(4), UInt64(2)
     int 4
     int 2
@@ -357,20 +360,29 @@ non_empty_tuple:
 
 // test_cases.tuple_support.tuple_support.get_uint_with_side_effect() -> uint64:
 get_uint_with_side_effect:
-    // tuple_support/tuple_support.py:65-66
+    // tuple_support/tuple_support.py:72-73
     // @subroutine
     // def get_uint_with_side_effect() -> UInt64:
     proto 0 1
-    // tuple_support/tuple_support.py:67
+    // tuple_support/tuple_support.py:74
     // log("get_uint_with_side_effect called")
     byte "get_uint_with_side_effect called"
     log
-    // tuple_support/tuple_support.py:68
+    // tuple_support/tuple_support.py:75
     // return UInt64(4)
     int 4
     retsub
 
 
+// test_cases.tuple_support.tuple_support.single_tuple() -> void:
+single_tuple:
+    // tuple_support/tuple_support.py:66-67
+    // @subroutine
+    // def single_tuple() -> None:
+    proto 0 0
+    retsub
+
+
 // test_cases.tuple_support.tuple_support.TupleSupport.__init__() -> void:
 __init__:
     // tuple_support/tuple_support.py:5

test_cases/tuple_support/out/TupleSupport.clear.mir

@@ -4,6 +4,6 @@
 
 // test_cases.tuple_support.tuple_support.TupleSupport.clear_state_program() -> uint64:
 main_block@0:
-    int 0  // 0              UInt64(0)        tuple_support/tuple_support.py:62
-    return //                return UInt64(0) tuple_support/tuple_support.py:62
+    int 0  // 0              UInt64(0)        tuple_support/tuple_support.py:63
+    return //                return UInt64(0) tuple_support/tuple_support.py:63
 

test_cases/tuple_support/out/TupleSupport.clear.teal

@@ -1,7 +1,7 @@
 #pragma version 10
 
 test_cases.tuple_support.tuple_support.TupleSupport.clear_state_program:
-    // tuple_support/tuple_support.py:62
+    // tuple_support/tuple_support.py:63
     // return UInt64(0)
     int 0
     return