Add array support for tuples

eth_abi/decoding.py

@@ -175,8 +175,19 @@ def decode(self, stream):
     @parse_tuple_type_str
     def from_type_str(cls, abi_type, registry):
         decoders = tuple(registry.get_decoder(str(c)) for c in abi_type.components)
-
-        return cls(decoders=decoders)
+        decoder = cls(decoders=decoders)
+        if abi_type.arrlist:
+            array_spec = abi_type.arrlist[-1]
+            if len(array_spec) == 1:
+                # If array dimension is fixed
+                return SizedArrayDecoder(
+                    array_size=array_spec[0],
+                    item_decoder=decoder,
+                )
+            else:
+                # If array dimension is dynamic
+                return DynamicArrayDecoder(item_decoder=decoder)
+        return decoder
 
 
 class SingleDecoder(BaseDecoder):

eth_abi/encoding.py

@@ -138,8 +138,19 @@ def encode(self, values):
     @parse_tuple_type_str
     def from_type_str(cls, abi_type, registry):
         encoders = tuple(registry.get_encoder(str(c)) for c in abi_type.components)
-
-        return cls(encoders=encoders)
+        encoder = cls(encoders=encoders)
+        if abi_type.arrlist:
+            array_spec = abi_type.arrlist[-1]
+            if len(array_spec) == 1:
+                # If array dimension is fixed
+                return SizedArrayEncoder(
+                    array_size=array_spec[0],
+                    item_encoder=encoder,
+                )
+            else:
+                # If array dimension is dynamic
+                return DynamicArrayEncoder(item_encoder=encoder)
+        return encoder
 
 
 class FixedSizeEncoder(BaseEncoder):

eth_abi/grammar.py

@@ -14,7 +14,8 @@
 grammar = parsimonious.Grammar(r"""
 type = tuple_type / basic_type
 
-tuple_type = non_zero_tuple / zero_tuple
+tuple_type = base_tuple_type arrlist?
+base_tuple_type = non_zero_tuple / zero_tuple
 
 non_zero_tuple = "(" type next_type* ")"
 next_type = "," type
@@ -48,7 +49,11 @@ def visit_non_zero_tuple(self, node, visited_children):
         # Ignore left and right parens
         _, first, rest, _ = visited_children
 
-        return TupleType((first,) + rest, node=node)
+        return (first,) + rest
+
+    def visit_tuple_type(self, node, visited_children):
+        base_tuple_type, arrlist = visited_children
+        return TupleType(base_tuple_type, arrlist=arrlist, node=node)
 
     def visit_next_type(self, node, visited_children):
         # Ignore comma
@@ -57,7 +62,7 @@ def visit_next_type(self, node, visited_children):
         return abi_type
 
     def visit_zero_tuple(self, node, visited_children):
-        return TupleType(tuple(), node=node)
+        return tuple()
 
     def visit_basic_type(self, node, visited_children):
         base, sub, arrlist = visited_children
@@ -184,15 +189,21 @@ class TupleType(ABIType):
 
     e.g. "(int,bool)"
     """
-    __slots__ = ('components',)
+    __slots__ = ('components', 'arrlist')
 
-    def __init__(self, components, *, node=None):
+    def __init__(self, components, arrlist=None, *, node=None):
         super().__init__(node=node)
 
         self.components = components
+        self.arrlist = arrlist
 
     def __str__(self):
-        return '({})'.format(','.join(str(c) for c in self.components))
+        arrlist = self.arrlist
+        if isinstance(arrlist, tuple):
+            arrlist = ''.join(repr(list(a)) for a in arrlist)
+        else:
+            arrlist = ''
+        return '({}){}'.format(','.join(str(c) for c in self.components), arrlist)
 
     def validate(self):
         # A tuple type is valid if all of its components are valid i.e. if none

tests/common/unit.py

@@ -115,6 +115,16 @@ def words(*descriptions: str) -> bytes:
         (((1, 1), 2), 3),
         words('40', '3', '40', '2', '2', '1', '1')
     ),
+    (
+        '((int,int)[])',
+        (((1, 2), (3, 4)),),
+        words('20', '2', '1', '2', '3', '4')
+    ),
+    (
+        '((int,int[],(int,int)[]),(int,int),int)',
+        ((1, (2, 3), ((4, 5), (6, 7))), (8, 9), 10),
+        words('80', '8', '9', 'a', '1', '60', 'c0', '2', '2', '3', '2', '4', '5', '6', '7')
+    ),
     (
         '((bytes,bool),(bytes,bool))',
         ((b'david attenborough', False), (b'boaty mcboatface', True)),