1 # This file is part of NIT ( http://www.nitlanguage.org ).
3 # Copyright 2012 Jean Privat <jean@pryen.org>
5 # Licensed under the Apache License, Version 2.0 (the "License");
6 # you may not use this file except in compliance with the License.
7 # You may obtain a copy of the License at
9 # http://www.apache.org/licenses/LICENSE-2.0
11 # Unless required by applicable law or agreed to in writing, software
12 # distributed under the License is distributed on an "AS IS" BASIS,
13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 # See the License for the specific language governing permissions and
15 # limitations under the License.
17 # Intraprocedural resolution of static types and OO-services
18 # By OO-services we mean message sending, attribute access, instantiation, etc.
24 redef class ToolContext
25 var typing_phase
: Phase = new TypingPhase(self, [flow_phase
, modelize_property_phase
, local_var_init_phase
])
28 private class TypingPhase
30 redef fun process_npropdef
(npropdef
) do npropdef
.do_typing
(toolcontext
.modelbuilder
)
33 private class TypeVisitor
34 var modelbuilder
: ModelBuilder
36 # The module of the analysis
37 # Used to correctly query the model
40 # The static type of the receiver
41 # Mainly used for type tests and type resolutions
42 var anchor
: nullable MClassType = null
44 # The analyzed mclassdef
45 var mclassdef
: nullable MClassDef = null
47 # The analyzed property
48 var mpropdef
: nullable MPropDef
50 var selfvariable
= new Variable("self")
52 # Is `self` use restricted?
53 # * no explicit `self`
54 # * method called on the implicit self must be top-level
55 # Currently only used for `new` factory since there is no valid receiver inside
56 var is_toplevel_context
= false
60 var mpropdef
= self.mpropdef
62 if mpropdef
!= null then
63 self.mpropdef
= mpropdef
64 var mclassdef
= mpropdef
.mclassdef
65 self.mclassdef
= mclassdef
66 self.anchor
= mclassdef
.bound_mtype
68 var mclass
= mclassdef
.mclass
70 var selfvariable
= new Variable("self")
71 self.selfvariable
= selfvariable
72 selfvariable
.declared_type
= mclass
.mclass_type
74 var mprop
= mpropdef
.mproperty
75 if mprop
isa MMethod and mprop
.is_new
then
76 is_toplevel_context
= true
81 fun anchor_to
(mtype
: MType): MType
84 if anchor
== null then
85 assert not mtype
.need_anchor
88 return mtype
.anchor_to
(mmodule
, anchor
)
91 fun is_subtype
(sub
, sup
: MType): Bool
93 return sub
.is_subtype
(mmodule
, anchor
, sup
)
96 fun resolve_for
(mtype
, subtype
: MType, for_self
: Bool): MType
98 #print "resolve_for {mtype} sub={subtype} forself={for_self} mmodule={mmodule} anchor={anchor}"
99 var res
= mtype
.resolve_for
(subtype
, anchor
, mmodule
, not for_self
)
103 # Check that `sub` is a subtype of `sup`.
104 # If `sub` is not a valid suptype, then display an error on `node` an return null.
105 # If `sub` is a safe subtype of `sup` then return `sub`.
106 # If `sub` is an unsafe subtype (ie an implicit cast is required), then return `sup`.
108 # The point of the return type is to determinate the usable type on an expression when `autocast` is true:
109 # If the suptype is safe, then the return type is the one on the expression typed by `sub`.
110 # Is the subtype is unsafe, then the return type is the one of an implicit cast on `sup`.
111 fun check_subtype
(node
: ANode, sub
, sup
: MType, autocast
: Bool): nullable MType
113 if self.is_subtype
(sub
, sup
) then return sub
114 if autocast
and self.is_subtype
(sub
, self.anchor_to
(sup
)) then
115 # FIXME workaround to the current unsafe typing policy. To remove once fixed virtual types exists.
116 #node.debug("Unsafe typing: expected {sup}, got {sub}")
119 if sub
.need_anchor
then
120 var u
= anchor_to
(sub
)
121 self.modelbuilder
.error
(node
, "Type Error: expected `{sup}`, got `{sub}: {u}`.")
123 self.modelbuilder
.error
(node
, "Type Error: expected `{sup}`, got `{sub}`.")
128 # Visit an expression and do not care about the return value
129 fun visit_stmt
(nexpr
: nullable AExpr)
131 if nexpr
== null then return
132 nexpr
.accept_typing
(self)
135 # Visit an expression and expects that it is not a statement
136 # Return the type of the expression
137 # Display an error and return null if:
138 # * the type cannot be determined or
139 # * `nexpr` is a statement
140 fun visit_expr
(nexpr
: AExpr): nullable MType
142 nexpr
.accept_typing
(self)
143 var mtype
= nexpr
.mtype
144 if mtype
!= null then return mtype
145 if not nexpr
.is_typed
then
146 if not self.modelbuilder
.toolcontext
.error_count
> 0 then # check that there is really an error
147 if self.modelbuilder
.toolcontext
.verbose_level
> 1 then
148 nexpr
.debug
("No return type but no error.")
151 return null # forward error
153 self.error
(nexpr
, "Error: expected an expression.")
157 # Visit an expression and expect its static type is a least a `sup`
158 # Return the type of the expression or null if
159 # * the type cannot be determined or
160 # * `nexpr` is a statement or
161 # * `nexpr` is not a `sup`
162 fun visit_expr_subtype
(nexpr
: AExpr, sup
: nullable MType): nullable MType
164 var sub
= visit_expr
(nexpr
)
165 if sub
== null then return null # Forward error
167 if sup
== null then return null # Forward error
169 var res
= check_subtype
(nexpr
, sub
, sup
, true)
171 nexpr
.implicit_cast_to
= res
176 # Visit an expression and expect its static type is a `Bool`
177 # Return the type of the expression or null if
178 # * the type cannot be determined or
179 # * `nexpr` is a statement or
180 # * `nexpr` is not a `Bool`
181 fun visit_expr_bool
(nexpr
: AExpr): nullable MType
183 return self.visit_expr_subtype
(nexpr
, self.type_bool
(nexpr
))
187 fun visit_expr_cast
(node
: ANode, nexpr
: AExpr, ntype
: AType): nullable MType
189 var sub
= visit_expr
(nexpr
)
190 if sub
== null then return null # Forward error
192 var sup
= self.resolve_mtype
(ntype
)
193 if sup
== null then return null # Forward error
196 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}`.")
197 else if self.is_subtype
(sub
, sup
) then
198 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}` since it is a `{sub}`.")
203 # Can `mtype` be null (up to the current knowledge)?
204 fun can_be_null
(mtype
: MType): Bool
206 if mtype
isa MNullableType or mtype
isa MNullType then return true
207 if mtype
isa MFormalType then
208 var x
= anchor_to
(mtype
)
209 if x
isa MNullableType or x
isa MNullType then return true
214 # Check that `mtype` can be null (up to the current knowledge).
216 # If not then display a `useless-null-test` warning on node and return false.
218 fun check_can_be_null
(anode
: ANode, mtype
: MType): Bool
220 if can_be_null
(mtype
) then return true
222 if mtype
isa MFormalType then
223 var res
= anchor_to
(mtype
)
224 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}: {res}`.")
226 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}`.")
231 # Special verification on != and == for null
233 fun null_test
(anode
: ABinopExpr)
235 var mtype
= anode
.n_expr
.mtype
236 var mtype2
= anode
.n_expr2
.mtype
238 if mtype
== null or mtype2
== null then return
240 if not mtype2
isa MNullType then return
242 # Check of useless null
243 if not check_can_be_null
(anode
.n_expr
, mtype
) then return
245 if mtype
isa MNullType then
246 # Because of type adaptation, we cannot just stop here
247 # so return use `null` as a bottom type that will be merged easily (cf) `merge_types`
250 mtype
= mtype
.as_notnull
253 # Check for type adaptation
254 var variable
= anode
.n_expr
.its_variable
255 if variable
== null then return
257 # One is null (mtype2 see above) the other is not null
258 if anode
isa AEqExpr then
259 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype2
)
260 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype
)
261 else if anode
isa ANeExpr then
262 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype2
)
263 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype
)
269 fun try_get_mproperty_by_name2
(anode
: ANode, mtype
: MType, name
: String): nullable MProperty
271 return self.modelbuilder
.try_get_mproperty_by_name2
(anode
, mmodule
, mtype
, name
)
274 fun resolve_mtype
(node
: AType): nullable MType
276 return self.modelbuilder
.resolve_mtype
(mmodule
, mclassdef
, node
)
279 fun try_get_mclass
(node
: ANode, name
: String): nullable MClass
281 var mclass
= modelbuilder
.try_get_mclass_by_name
(node
, mmodule
, name
)
285 fun get_mclass
(node
: ANode, name
: String): nullable MClass
287 var mclass
= modelbuilder
.get_mclass_by_name
(node
, mmodule
, name
)
291 fun type_bool
(node
: ANode): nullable MType
293 var mclass
= self.get_mclass
(node
, "Bool")
294 if mclass
== null then return null
295 return mclass
.mclass_type
298 fun get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
300 var unsafe_type
= self.anchor_to
(recvtype
)
302 #debug("recv: {recvtype} (aka {unsafe_type})")
303 if recvtype
isa MNullType then
304 var objclass
= get_mclass
(node
, "Object")
305 if objclass
== null then return null # Forward error
306 unsafe_type
= objclass
.mclass_type
309 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
310 if name
== "new" and mproperty
== null then
312 mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
315 if mproperty
== null then
317 self.modelbuilder
.error
(node
, "Error: method or variable `{name}` unknown in `{recvtype}`.")
318 else if recvtype
.need_anchor
then
319 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}: {unsafe_type}`.")
321 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}`.")
326 assert mproperty
isa MMethod
328 # `null` only accepts some methods of object.
329 if recvtype
isa MNullType and not mproperty
.is_null_safe
then
330 self.error
(node
, "Error: method `{name}` called on `null`.")
332 else if unsafe_type
isa MNullableType and not mproperty
.is_null_safe
then
333 modelbuilder
.advice
(node
, "call-on-nullable", "Warning: method call on a nullable receiver `{recvtype}`.")
336 if is_toplevel_context
and recv_is_self
and not mproperty
.is_toplevel
then
337 error
(node
, "Error: `{name}` is not a top-level method, thus need a receiver.")
339 if not recv_is_self
and mproperty
.is_toplevel
then
340 error
(node
, "Error: cannot call `{name}`, a top-level method, with a receiver.")
343 if mproperty
.visibility
== protected_visibility
and not recv_is_self
and self.mmodule
.visibility_for
(mproperty
.intro_mclassdef
.mmodule
) < intrude_visibility
and not modelbuilder
.toolcontext
.opt_ignore_visibility
.value
then
344 self.modelbuilder
.error
(node
, "Error: method `{name}` is protected and can only accessed by `self`.")
348 var info
= mproperty
.deprecation
349 if info
!= null and self.mpropdef
.mproperty
.deprecation
== null then
352 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated: {mdoc.content.first}")
354 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated.")
358 var propdefs
= mproperty
.lookup_definitions
(self.mmodule
, unsafe_type
)
360 if propdefs
.length
== 0 then
361 self.modelbuilder
.error
(node
, "Type Error: no definition found for property `{name}` in `{unsafe_type}`.")
363 else if propdefs
.length
== 1 then
364 mpropdef
= propdefs
.first
366 self.modelbuilder
.warning
(node
, "property-conflict", "Warning: conflicting property definitions for property `{name}` in `{unsafe_type}`: {propdefs.join(" ")}")
367 mpropdef
= mproperty
.intro
371 var msignature
= mpropdef
.new_msignature
or else mpropdef
.msignature
372 if msignature
== null then return null # skip error
373 msignature
= resolve_for
(msignature
, recvtype
, recv_is_self
).as(MSignature)
375 var erasure_cast
= false
376 var rettype
= mpropdef
.msignature
.return_mtype
377 if not recv_is_self
and rettype
!= null then
378 rettype
= rettype
.undecorate
379 if rettype
isa MParameterType then
380 var erased_rettype
= msignature
.return_mtype
381 assert erased_rettype
!= null
382 #node.debug("Erasure cast: Really a {rettype} but unsafely a {erased_rettype}")
387 var callsite
= new CallSite(node
, recvtype
, mmodule
, anchor
, recv_is_self
, mproperty
, mpropdef
, msignature
, erasure_cast
)
391 fun try_get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
393 var unsafe_type
= self.anchor_to
(recvtype
)
394 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
395 if mproperty
== null then return null
396 return get_method
(node
, recvtype
, name
, recv_is_self
)
400 # Visit the expressions of args and check their conformity with the corresponding type in signature
401 # The point of this method is to handle varargs correctly
402 # Note: The signature must be correctly adapted
403 fun check_signature
(node
: ANode, args
: Array[AExpr], mproperty
: MProperty, msignature
: MSignature): nullable SignatureMap
405 var vararg_rank
= msignature
.vararg_rank
406 if vararg_rank
>= 0 then
407 if args
.length
< msignature
.arity
then
408 modelbuilder
.error
(node
, "Error: expected at least {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
411 else if args
.length
!= msignature
.arity
then
412 if msignature
.arity
== msignature
.min_arity
then
413 modelbuilder
.error
(node
, "Error: expected {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
416 if args
.length
> msignature
.arity
then
417 modelbuilder
.error
(node
, "Error: expected at most {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
420 if args
.length
< msignature
.min_arity
then
421 modelbuilder
.error
(node
, "Error: expected at least {msignature.min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
426 #debug("CALL {unsafe_type}.{msignature}")
428 # Associate each parameter to a position in the arguments
429 var map
= new SignatureMap
431 var setted
= args
.length
- msignature
.min_arity
433 # First, handle named arguments
434 for i
in [0..args
.length
[ do
436 if not e
isa ANamedargExpr then continue
437 var name
= e
.n_id
.text
438 var param
= msignature
.mparameter_by_name
(name
)
439 if param
== null then
440 modelbuilder
.error
(e
.n_id
, "Error: no parameter `{name}` for `{mproperty}{msignature}`.")
443 if not param
.is_default
then
444 modelbuilder
.error
(e
, "Error: parameter `{name}` is not optional for `{mproperty}{msignature}`.")
447 var idx
= msignature
.mparameters
.index_of
(param
)
448 var prev
= map
.map
.get_or_null
(idx
)
450 modelbuilder
.error
(e
, "Error: parameter `{name}` already associated with argument #{prev} for `{mproperty}{msignature}`.")
455 e
.mtype
= self.visit_expr_subtype
(e
.n_expr
, param
.mtype
)
458 # Second, associate remaining parameters
459 var vararg_decl
= args
.length
- msignature
.arity
461 for i
in [0..msignature
.arity
[ do
462 # Skip parameters associated by name
463 if map
.map
.has_key
(i
) then continue
465 var param
= msignature
.mparameters
[i
]
466 if param
.is_default
then
474 # Search the next free argument: skip named arguments since they are already associated
475 while args
[j
] isa ANamedargExpr do j
+= 1
480 if i
== vararg_rank
then
482 continue # skip the vararg
485 var paramtype
= param
.mtype
486 self.visit_expr_subtype
(arg
, paramtype
)
489 # Third, check varargs
490 if vararg_rank
>= 0 then
491 var paramtype
= msignature
.mparameters
[vararg_rank
].mtype
492 var first
= args
[vararg_rank
]
493 if vararg_decl
== 0 then
494 var mclass
= get_mclass
(node
, "Array")
495 if mclass
== null then return null # Forward error
496 var array_mtype
= mclass
.get_mtype
([paramtype
])
497 if first
isa AVarargExpr then
498 self.visit_expr_subtype
(first
.n_expr
, array_mtype
)
499 first
.mtype
= first
.n_expr
.mtype
501 # only one vararg, maybe `...` was forgot, so be gentle!
502 var t
= visit_expr
(first
)
503 if t
== null then return null # Forward error
504 if not is_subtype
(t
, paramtype
) and is_subtype
(t
, array_mtype
) then
505 # Not acceptable but could be a `...`
506 error
(first
, "Type Error: expected `{paramtype}`, got `{t}`. Is an ellipsis `...` missing on the argument?")
509 # Standard valid vararg, finish the job
511 self.visit_expr_subtype
(first
, paramtype
)
514 map
.vararg_decl
= vararg_decl
+ 1
515 for i
in [vararg_rank
..vararg_rank
+vararg_decl
] do
516 self.visit_expr_subtype
(args
[i
], paramtype
)
524 fun error
(node
: ANode, message
: String)
526 self.modelbuilder
.toolcontext
.error
(node
.hot_location
, message
)
529 fun get_variable
(node
: AExpr, variable
: Variable): nullable MType
531 if not variable
.is_adapted
then return variable
.declared_type
533 var flow
= node
.after_flow_context
534 if flow
== null then return null # skip error
536 if flow
.vars
.has_key
(variable
) then
537 return flow
.vars
[variable
]
539 #node.debug("*** START Collected for {variable}")
540 var mtypes
= flow
.collect_types
(variable
)
541 #node.debug("**** END Collected for {variable}")
542 if mtypes
.length
== 0 then
543 return variable
.declared_type
544 else if mtypes
.length
== 1 then
547 var res
= merge_types
(node
,mtypes
)
548 if res
== null then res
= variable
.declared_type
554 # Some variables where type-adapted during the visit
557 # Some loops had been visited during the visit
560 fun set_variable
(node
: AExpr, variable
: Variable, mtype
: nullable MType)
562 var flow
= node
.after_flow_context
565 flow
.set_var
(self, variable
, mtype
)
568 fun merge_types
(node
: ANode, col
: Array[nullable MType]): nullable MType
570 if col
.length
== 1 then return col
.first
572 if t1
== null then continue # return null
575 if t2
== null then continue # return null
576 if can_be_null
(t2
) and not can_be_null
(t1
) then
579 if not is_subtype
(t2
, t1
) then found
= false
582 #print "merge {col.join(" ")} -> {t1}"
586 #self.modelbuilder.warning(node, "Type Error: {col.length} conflicting types: <{col.join(", ")}>")
591 # Mapping between parameters and arguments in a call.
593 # Parameters and arguments are not stored in the class but referenced by their position (starting from 0)
595 # The point of this class is to help engine and other things to map arguments in the AST to parameters of the model.
597 # Associate a parameter to an argument
598 var map
= new ArrayMap[Int, Int]
600 # The length of the vararg sequence
601 # 0 if no vararg or if reverse vararg (cf `AVarargExpr`)
602 var vararg_decl
: Int = 0
605 # A specific method call site with its associated informations.
607 # The associated node for location
610 # The static type of the receiver (possibly unresolved)
613 # The module where the callsite is present
616 # The anchor to use with `recv` or `msignature`
617 var anchor
: nullable MClassType
619 # Is the receiver self?
620 # If "for_self", virtual types of the signature are kept
621 # If "not_for_self", virtual type are erased
622 var recv_is_self
: Bool
624 # The designated method
625 var mproperty
: MMethod
627 # The statically designated method definition
628 # The most specif one, it is.
629 var mpropdef
: MMethodDef
631 # The resolved signature for the receiver
632 var msignature
: MSignature
634 # Is a implicit cast required on erasure typing policy?
635 var erasure_cast
: Bool
637 # The mapping used on the call to associate arguments to parameters
638 # If null then no specific association is required.
639 var signaturemap
: nullable SignatureMap = null
641 private fun check_signature
(v
: TypeVisitor, args
: Array[AExpr]): Bool
643 var map
= v
.check_signature
(self.node
, args
, self.mproperty
, self.msignature
)
650 # The declared type of the variable
651 var declared_type
: nullable MType is writable
653 # Was the variable type-adapted?
654 # This is used to speedup type retrieval while it remains `false`
655 private var is_adapted
= false
658 redef class FlowContext
659 # Store changes of types because of type evolution
660 private var vars
= new HashMap[Variable, nullable MType]
662 # Adapt the variable to a static type
663 # Warning1: do not modify vars directly.
664 # Warning2: sub-flow may have cached a unadapted variable
665 private fun set_var
(v
: TypeVisitor, variable
: Variable, mtype
: nullable MType)
667 if variable
.declared_type
== mtype
and not variable
.is_adapted
then return
668 if vars
.has_key
(variable
) and vars
[variable
] == mtype
then return
669 self.vars
[variable
] = mtype
671 variable
.is_adapted
= true
672 #node.debug "set {variable} to {mtype or else "X"}"
675 # Look in the flow and previous flow and collect all first reachable type adaptation of a local variable
676 private fun collect_types
(variable
: Variable): Array[nullable MType]
678 #node.debug "flow for {variable}"
679 var res
= new Array[nullable MType]
682 var seen
= new HashSet[FlowContext]
683 while not todo
.is_empty
do
685 if f
.is_unreachable
then continue
686 if seen
.has
(f
) then continue
689 if f
.vars
.has_key
(variable
) then
690 # Found something. Collect it and do not process further on this path
691 res
.add f
.vars
[variable
]
692 #f.node.debug "process {variable}: got {f.vars[variable] or else "X"}"
694 todo
.add_all f
.previous
696 if f
.previous
.is_empty
then
697 # Root flowcontext mean a parameter or something related
698 res
.add variable
.declared_type
699 #f.node.debug "root process {variable}: got {variable.declared_type or else "X"}"
703 #self.node.debug "##### end flow for {variable}: {res.join(" ")}"
709 # The entry point of the whole typing analysis
710 fun do_typing
(modelbuilder
: ModelBuilder)
714 # The variable associated to the receiver (if any)
715 var selfvariable
: nullable Variable
718 redef class AMethPropdef
719 redef fun do_typing
(modelbuilder
: ModelBuilder)
721 var nblock
= self.n_block
722 if nblock
== null then return
724 var mpropdef
= self.mpropdef
725 if mpropdef
== null then return # skip error
727 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
728 self.selfvariable
= v
.selfvariable
730 var mmethoddef
= self.mpropdef
.as(not null)
731 var msignature
= mmethoddef
.msignature
732 if msignature
== null then return # skip error
733 for i
in [0..msignature
.arity
[ do
734 var mtype
= msignature
.mparameters
[i
].mtype
735 if msignature
.vararg_rank
== i
then
736 var arrayclass
= v
.get_mclass
(self.n_signature
.n_params
[i
], "Array")
737 if arrayclass
== null then return # Skip error
738 mtype
= arrayclass
.get_mtype
([mtype
])
740 var variable
= self.n_signature
.n_params
[i
].variable
741 assert variable
!= null
742 variable
.declared_type
= mtype
748 if not v
.has_loop
or not v
.dirty
then break
751 if not nblock
.after_flow_context
.is_unreachable
and msignature
.return_mtype
!= null then
752 # We reach the end of the function without having a return, it is bad
753 v
.error
(self, "Error: reached end of function; expected `return` with a value.")
758 redef class AAttrPropdef
759 redef fun do_typing
(modelbuilder
: ModelBuilder)
761 if not has_value
then return
763 var mpropdef
= self.mreadpropdef
764 if mpropdef
== null or mpropdef
.msignature
== null then return # skip error
766 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
767 self.selfvariable
= v
.selfvariable
769 var nexpr
= self.n_expr
770 if nexpr
!= null then
771 var mtype
= self.mtype
772 v
.visit_expr_subtype
(nexpr
, mtype
)
774 var nblock
= self.n_block
775 if nblock
!= null then
777 if not nblock
.after_flow_context
.is_unreachable
then
778 # We reach the end of the init without having a return, it is bad
779 v
.error
(self, "Error: reached end of block; expected `return`.")
788 # The static type of the expression.
789 # null if self is a statement or in case of error
790 var mtype
: nullable MType = null
792 # Is the statement correctly typed?
793 # Used to distinguish errors and statements when `mtype == null`
794 var is_typed
: Bool = false
796 # If required, the following implicit cast `.as(XXX)`
797 # Such a cast may by required after evaluating the expression when
798 # a unsafe operation is detected (silently accepted by the Nit language).
799 # The attribute is computed by `check_subtype`
800 var implicit_cast_to
: nullable MType = null
802 # Return the variable read (if any)
803 # Used to perform adaptive typing
804 fun its_variable
: nullable Variable do return null
806 private fun accept_typing
(v
: TypeVisitor)
808 v
.error
(self, "no implemented accept_typing for {self.class_name}")
811 # Is non-null if `self` is a leaf of a comprehension array construction.
812 # In this case, the enclosing literal array node is designated.
813 # The result of the evaluation of `self` must be
814 # stored inside the designated array (there is an implicit `push`)
815 var comprehension
: nullable AArrayExpr = null
818 redef class ABlockExpr
819 redef fun accept_typing
(v
)
821 for e
in self.n_expr
do v
.visit_stmt
(e
)
825 # The type of a blockexpr is the one of the last expression (or null if empty)
828 if self.n_expr
.is_empty
then return null
829 return self.n_expr
.last
.mtype
833 redef class AVardeclExpr
834 redef fun accept_typing
(v
)
836 var variable
= self.variable
837 if variable
== null then return # Skip error
839 var ntype
= self.n_type
840 var mtype
: nullable MType
841 if ntype
== null then
844 mtype
= v
.resolve_mtype
(ntype
)
845 if mtype
== null then return # Skip error
848 var nexpr
= self.n_expr
849 if nexpr
!= null then
850 if mtype
!= null then
851 var etype
= v
.visit_expr_subtype
(nexpr
, mtype
)
852 if etype
== mtype
then
854 v
.modelbuilder
.advice
(ntype
, "useless-type", "Warning: useless type definition for variable `{variable.name}`")
857 mtype
= v
.visit_expr
(nexpr
)
858 if mtype
== null then return # Skip error
863 if mtype
== null or mtype
isa MNullType then
864 var objclass
= v
.get_mclass
(self, "Object")
865 if objclass
== null then return # skip error
866 decltype
= objclass
.mclass_type
.as_nullable
867 if mtype
== null then mtype
= decltype
870 variable
.declared_type
= decltype
871 v
.set_variable
(self, variable
, mtype
)
873 #debug("var {variable}: {mtype}")
881 redef fun its_variable
do return self.variable
882 redef fun accept_typing
(v
)
884 var variable
= self.variable
885 if variable
== null then return # Skip error
887 var mtype
= v
.get_variable
(self, variable
)
888 if mtype
!= null then
889 #debug("{variable} is {mtype}")
891 #debug("{variable} is untyped")
898 redef class AVarAssignExpr
899 redef fun accept_typing
(v
)
901 var variable
= self.variable
902 assert variable
!= null
904 var mtype
= v
.visit_expr_subtype
(n_value
, variable
.declared_type
)
906 v
.set_variable
(self, variable
, mtype
)
912 redef class AReassignFormExpr
913 # The method designed by the reassign operator.
914 var reassign_callsite
: nullable CallSite
916 var read_type
: nullable MType = null
918 # Determine the `reassign_property`
919 # `readtype` is the type of the reading of the left value.
920 # `writetype` is the type of the writing of the left value.
921 # (Because of `ACallReassignExpr`, both can be different.
922 # Return the static type of the value to store.
923 private fun resolve_reassignment
(v
: TypeVisitor, readtype
, writetype
: MType): nullable MType
925 var reassign_name
= self.n_assign_op
.operator
927 self.read_type
= readtype
929 var callsite
= v
.get_method
(self.n_assign_op
, readtype
, reassign_name
, false)
930 if callsite
== null then return null # Skip error
931 self.reassign_callsite
= callsite
933 var msignature
= callsite
.msignature
934 var rettype
= msignature
.return_mtype
935 assert msignature
.arity
== 1 and rettype
!= null
937 var value_type
= v
.visit_expr_subtype
(self.n_value
, msignature
.mparameters
.first
.mtype
)
938 if value_type
== null then return null # Skip error
940 v
.check_subtype
(self, rettype
, writetype
, false)
945 redef class AVarReassignExpr
946 redef fun accept_typing
(v
)
948 var variable
= self.variable
949 assert variable
!= null
951 var readtype
= v
.get_variable
(self, variable
)
952 if readtype
== null then return
956 var writetype
= variable
.declared_type
957 if writetype
== null then return
959 var rettype
= self.resolve_reassignment
(v
, readtype
, writetype
)
961 v
.set_variable
(self, variable
, rettype
)
963 self.is_typed
= rettype
!= null
968 redef class AContinueExpr
969 redef fun accept_typing
(v
)
971 var nexpr
= self.n_expr
972 if nexpr
!= null then
979 redef class ABreakExpr
980 redef fun accept_typing
(v
)
982 var nexpr
= self.n_expr
983 if nexpr
!= null then
990 redef class AReturnExpr
991 redef fun accept_typing
(v
)
993 var nexpr
= self.n_expr
995 var mpropdef
= v
.mpropdef
996 if mpropdef
isa MMethodDef then
997 ret_type
= mpropdef
.msignature
.return_mtype
998 else if mpropdef
isa MAttributeDef then
999 ret_type
= mpropdef
.static_mtype
1003 if nexpr
!= null then
1004 if ret_type
!= null then
1005 v
.visit_expr_subtype
(nexpr
, ret_type
)
1008 v
.error
(nexpr
, "Error: `return` with value in a procedure.")
1011 else if ret_type
!= null then
1012 v
.error
(self, "Error: `return` without value in a function.")
1015 self.is_typed
= true
1019 redef class AAbortExpr
1020 redef fun accept_typing
(v
)
1022 self.is_typed
= true
1027 redef fun accept_typing
(v
)
1029 v
.visit_expr_bool
(n_expr
)
1031 v
.visit_stmt
(n_then
)
1032 v
.visit_stmt
(n_else
)
1034 self.is_typed
= true
1036 if n_then
!= null and n_else
== null then
1037 self.mtype
= n_then
.mtype
1042 redef class AIfexprExpr
1043 redef fun accept_typing
(v
)
1045 v
.visit_expr_bool
(n_expr
)
1047 var t1
= v
.visit_expr
(n_then
)
1048 var t2
= v
.visit_expr
(n_else
)
1050 if t1
== null or t2
== null then
1054 var t
= v
.merge_types
(self, [t1
, t2
])
1056 v
.error
(self, "Type Error: ambiguous type `{t1}` vs `{t2}`.")
1063 redef fun accept_typing
(v
)
1065 v
.visit_stmt
(n_block
)
1066 self.is_typed
= true
1070 redef class AWhileExpr
1071 redef fun accept_typing
(v
)
1074 v
.visit_expr_bool
(n_expr
)
1075 v
.visit_stmt
(n_block
)
1076 self.is_typed
= true
1080 redef class ALoopExpr
1081 redef fun accept_typing
(v
)
1084 v
.visit_stmt
(n_block
)
1085 self.is_typed
= true
1089 redef class AForExpr
1090 var coltype
: nullable MClassType
1092 var method_iterator
: nullable CallSite
1093 var method_is_ok
: nullable CallSite
1094 var method_item
: nullable CallSite
1095 var method_next
: nullable CallSite
1096 var method_key
: nullable CallSite
1097 var method_finish
: nullable CallSite
1099 var method_lt
: nullable CallSite
1100 var method_successor
: nullable CallSite
1102 private fun do_type_iterator
(v
: TypeVisitor, mtype
: MType)
1104 if mtype
isa MNullType then
1105 v
.error
(self, "Type Error: `for` cannot iterate over `null`.")
1110 var objcla
= v
.get_mclass
(self, "Object")
1111 if objcla
== null then return
1113 # check iterator method
1114 var itdef
= v
.get_method
(self, mtype
, "iterator", n_expr
isa ASelfExpr)
1115 if itdef
== null then
1116 v
.error
(self, "Type Error: `for` expects a type providing an `iterator` method, got `{mtype}`.")
1119 self.method_iterator
= itdef
1121 # check that iterator return something
1122 var ittype
= itdef
.msignature
.return_mtype
1123 if ittype
== null then
1124 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1129 var colit_cla
= v
.try_get_mclass
(self, "Iterator")
1130 var mapit_cla
= v
.try_get_mclass
(self, "MapIterator")
1134 if colit_cla
!= null and v
.is_subtype
(ittype
, colit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
])) then
1136 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, colit_cla
)
1137 var variables
= self.variables
1138 if variables
.length
!= 1 then
1139 v
.error
(self, "Type Error: `for` expects only one variable when using `Iterator`.")
1141 variables
.first
.declared_type
= coltype
.arguments
.first
1146 if mapit_cla
!= null and v
.is_subtype
(ittype
, mapit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
, objcla
.mclass_type
.as_nullable
])) then
1148 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, mapit_cla
)
1149 var variables
= self.variables
1150 if variables
.length
!= 2 then
1151 v
.error
(self, "Type Error: `for` expects two variables when using `MapIterator`.")
1153 variables
[0].declared_type
= coltype
.arguments
[0]
1154 variables
[1].declared_type
= coltype
.arguments
[1]
1159 if not is_col
and not is_map
then
1160 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1164 # anchor formal and virtual types
1165 if mtype
.need_anchor
then mtype
= v
.anchor_to
(mtype
)
1167 mtype
= mtype
.undecorate
1168 self.coltype
= mtype
.as(MClassType)
1170 # get methods is_ok, next, item
1171 var ikdef
= v
.get_method
(self, ittype
, "is_ok", false)
1172 if ikdef
== null then
1173 v
.error
(self, "Type Error: `for` expects a method `is_ok` in type `{ittype}`.")
1176 self.method_is_ok
= ikdef
1178 var itemdef
= v
.get_method
(self, ittype
, "item", false)
1179 if itemdef
== null then
1180 v
.error
(self, "Type Error: `for` expects a method `item` in type `{ittype}`.")
1183 self.method_item
= itemdef
1185 var nextdef
= v
.get_method
(self, ittype
, "next", false)
1186 if nextdef
== null then
1187 v
.error
(self, "Type Error: `for` expects a method `next` in type {ittype}.")
1190 self.method_next
= nextdef
1192 self.method_finish
= v
.try_get_method
(self, ittype
, "finish", false)
1195 var keydef
= v
.get_method
(self, ittype
, "key", false)
1196 if keydef
== null then
1197 v
.error
(self, "Type Error: `for` expects a method `key` in type `{ittype}`.")
1200 self.method_key
= keydef
1203 if self.variables
.length
== 1 and n_expr
isa ARangeExpr then
1204 var variable
= variables
.first
1205 var vtype
= variable
.declared_type
.as(not null)
1207 if n_expr
isa AOrangeExpr then
1208 self.method_lt
= v
.get_method
(self, vtype
, "<", false)
1210 self.method_lt
= v
.get_method
(self, vtype
, "<=", false)
1213 self.method_successor
= v
.get_method
(self, vtype
, "successor", false)
1217 redef fun accept_typing
(v
)
1220 var mtype
= v
.visit_expr
(n_expr
)
1221 if mtype
== null then return
1223 self.do_type_iterator
(v
, mtype
)
1225 v
.visit_stmt
(n_block
)
1227 self.mtype
= n_block
.mtype
1228 self.is_typed
= true
1232 redef class AWithExpr
1233 var method_start
: nullable CallSite
1234 var method_finish
: nullable CallSite
1236 redef fun accept_typing
(v
: TypeVisitor)
1238 var mtype
= v
.visit_expr
(n_expr
)
1239 if mtype
== null then return
1241 method_start
= v
.get_method
(self, mtype
, "start", n_expr
isa ASelfExpr)
1242 method_finish
= v
.get_method
(self, mtype
, "finish", n_expr
isa ASelfExpr)
1244 v
.visit_stmt
(n_block
)
1245 self.mtype
= n_block
.mtype
1246 self.is_typed
= true
1250 redef class AAssertExpr
1251 redef fun accept_typing
(v
)
1253 v
.visit_expr_bool
(n_expr
)
1255 v
.visit_stmt
(n_else
)
1256 self.is_typed
= true
1261 redef fun accept_typing
(v
)
1263 v
.visit_expr_bool
(n_expr
)
1264 v
.visit_expr_bool
(n_expr2
)
1265 self.mtype
= v
.type_bool
(self)
1269 redef class AImpliesExpr
1270 redef fun accept_typing
(v
)
1272 v
.visit_expr_bool
(n_expr
)
1273 v
.visit_expr_bool
(n_expr2
)
1274 self.mtype
= v
.type_bool
(self)
1278 redef class AAndExpr
1279 redef fun accept_typing
(v
)
1281 v
.visit_expr_bool
(n_expr
)
1282 v
.visit_expr_bool
(n_expr2
)
1283 self.mtype
= v
.type_bool
(self)
1288 redef class ANotExpr
1289 redef fun accept_typing
(v
)
1291 v
.visit_expr_bool
(n_expr
)
1292 self.mtype
= v
.type_bool
(self)
1296 redef class AOrElseExpr
1297 redef fun accept_typing
(v
)
1299 var t1
= v
.visit_expr
(n_expr
)
1300 var t2
= v
.visit_expr
(n_expr2
)
1302 if t1
== null or t2
== null then
1306 if t1
isa MNullType then
1307 v
.error
(n_expr
, "Type Error: `or else` on `null`.")
1308 else if v
.check_can_be_null
(n_expr
, t1
) then
1312 var t
= v
.merge_types
(self, [t1
, t2
])
1314 var c
= v
.get_mclass
(self, "Object")
1315 if c
== null then return # forward error
1317 if v
.can_be_null
(t2
) then
1320 #v.error(self, "Type Error: ambiguous type {t1} vs {t2}")
1326 redef class ATrueExpr
1327 redef fun accept_typing
(v
)
1329 self.mtype
= v
.type_bool
(self)
1333 redef class AFalseExpr
1334 redef fun accept_typing
(v
)
1336 self.mtype
= v
.type_bool
(self)
1340 redef class AIntExpr
1341 redef fun accept_typing
(v
)
1343 var mclass
= v
.get_mclass
(self, "Int")
1344 if mclass
== null then return # Forward error
1345 self.mtype
= mclass
.mclass_type
1349 redef class AByteExpr
1350 redef fun accept_typing
(v
)
1352 var mclass
= v
.get_mclass
(self, "Byte")
1353 if mclass
== null then return # Forward error
1354 self.mtype
= mclass
.mclass_type
1358 redef class AFloatExpr
1359 redef fun accept_typing
(v
)
1361 var mclass
= v
.get_mclass
(self, "Float")
1362 if mclass
== null then return # Forward error
1363 self.mtype
= mclass
.mclass_type
1367 redef class ACharExpr
1368 redef fun accept_typing
(v
)
1370 var mclass
= v
.get_mclass
(self, "Char")
1371 if mclass
== null then return # Forward error
1372 self.mtype
= mclass
.mclass_type
1376 redef class AStringFormExpr
1377 redef fun accept_typing
(v
)
1379 var mclass
= v
.get_mclass
(self, "String")
1380 if mclass
== null then return # Forward error
1381 self.mtype
= mclass
.mclass_type
1385 redef class ASuperstringExpr
1386 redef fun accept_typing
(v
)
1388 var mclass
= v
.get_mclass
(self, "String")
1389 if mclass
== null then return # Forward error
1390 self.mtype
= mclass
.mclass_type
1391 var objclass
= v
.get_mclass
(self, "Object")
1392 if objclass
== null then return # Forward error
1393 var objtype
= objclass
.mclass_type
1394 for nexpr
in self.n_exprs
do
1395 v
.visit_expr_subtype
(nexpr
, objtype
)
1400 redef class AArrayExpr
1401 # The `with_capacity` method on Array
1402 var with_capacity_callsite
: nullable CallSite
1404 # The `push` method on arrays
1405 var push_callsite
: nullable CallSite
1407 # The element of each type
1408 var element_mtype
: nullable MType
1410 # Set that `self` is a part of comprehension array `na`
1411 # If `self` is a `for`, or a `if`, then `set_comprehension` is recursively applied.
1412 private fun set_comprehension
(n
: nullable AExpr)
1416 else if n
isa AForExpr then
1417 set_comprehension
(n
.n_block
)
1418 else if n
isa AIfExpr then
1419 set_comprehension
(n
.n_then
)
1420 set_comprehension
(n
.n_else
)
1423 n
.comprehension
= self
1426 redef fun accept_typing
(v
)
1428 var mtype
: nullable MType = null
1429 var ntype
= self.n_type
1430 if ntype
!= null then
1431 mtype
= v
.resolve_mtype
(ntype
)
1432 if mtype
== null then return # Skip error
1434 var mtypes
= new Array[nullable MType]
1436 for e
in self.n_exprs
do
1437 var t
= v
.visit_expr
(e
)
1441 set_comprehension
(e
)
1442 if mtype
!= null then
1443 if v
.check_subtype
(e
, t
, mtype
, false) == null then return # Forward error
1444 if t
== mtype
then useless
= true
1449 if mtype
== null then
1450 # Ensure monotony for type adaptation on loops
1451 if self.element_mtype
!= null then mtypes
.add
self.element_mtype
1452 mtype
= v
.merge_types
(self, mtypes
)
1454 if mtype
== null or mtype
isa MNullType then
1455 v
.error
(self, "Type Error: ambiguous array type {mtypes.join(" ")}")
1459 assert ntype
!= null
1460 v
.modelbuilder
.warning
(ntype
, "useless-type", "Warning: useless type declaration `{mtype}` in literal Array since it can be inferred from the elements type.")
1463 self.element_mtype
= mtype
1465 var mclass
= v
.get_mclass
(self, "Array")
1466 if mclass
== null then return # Forward error
1467 var array_mtype
= mclass
.get_mtype
([mtype
])
1469 with_capacity_callsite
= v
.get_method
(self, array_mtype
, "with_capacity", false)
1470 push_callsite
= v
.get_method
(self, array_mtype
, "push", false)
1472 self.mtype
= array_mtype
1476 redef class ARangeExpr
1477 var init_callsite
: nullable CallSite
1479 redef fun accept_typing
(v
)
1481 var discrete_class
= v
.get_mclass
(self, "Discrete")
1482 if discrete_class
== null then return # Forward error
1483 var discrete_type
= discrete_class
.intro
.bound_mtype
1484 var t1
= v
.visit_expr_subtype
(self.n_expr
, discrete_type
)
1485 var t2
= v
.visit_expr_subtype
(self.n_expr2
, discrete_type
)
1486 if t1
== null or t2
== null then return
1487 var mclass
= v
.get_mclass
(self, "Range")
1488 if mclass
== null then return # Forward error
1490 if v
.is_subtype
(t1
, t2
) then
1491 mtype
= mclass
.get_mtype
([t2
])
1492 else if v
.is_subtype
(t2
, t1
) then
1493 mtype
= mclass
.get_mtype
([t1
])
1495 v
.error
(self, "Type Error: cannot create range: `{t1}` vs `{t2}`.")
1501 # get the constructor
1503 if self isa ACrangeExpr then
1504 callsite
= v
.get_method
(self, mtype
, "init", false)
1505 else if self isa AOrangeExpr then
1506 callsite
= v
.get_method
(self, mtype
, "without_last", false)
1510 init_callsite
= callsite
1514 redef class ANullExpr
1515 redef fun accept_typing
(v
)
1517 self.mtype
= v
.mmodule
.model
.null_type
1521 redef class AIsaExpr
1522 # The static type to cast to.
1523 # (different from the static type of the expression that is `Bool`).
1524 var cast_type
: nullable MType
1525 redef fun accept_typing
(v
)
1527 var mtype
= v
.visit_expr_cast
(self, self.n_expr
, self.n_type
)
1528 self.cast_type
= mtype
1530 var variable
= self.n_expr
.its_variable
1531 if variable
!= null then
1532 #var orig = self.n_expr.mtype
1533 #var from = if orig != null then orig.to_s else "invalid"
1534 #var to = if mtype != null then mtype.to_s else "invalid"
1535 #debug("adapt {variable}: {from} -> {to}")
1536 self.after_flow_context
.when_true
.set_var
(v
, variable
, mtype
)
1539 self.mtype
= v
.type_bool
(self)
1543 redef class AAsCastExpr
1544 redef fun accept_typing
(v
)
1546 self.mtype
= v
.visit_expr_cast
(self, self.n_expr
, self.n_type
)
1550 redef class AAsNotnullExpr
1551 redef fun accept_typing
(v
)
1553 var mtype
= v
.visit_expr
(self.n_expr
)
1554 if mtype
== null then return # Forward error
1556 if mtype
isa MNullType then
1557 v
.error
(self, "Type Error: `as(not null)` on `null`.")
1561 if v
.check_can_be_null
(n_expr
, mtype
) then
1562 mtype
= mtype
.as_notnull
1569 redef class AParExpr
1570 redef fun accept_typing
(v
)
1572 self.mtype
= v
.visit_expr
(self.n_expr
)
1576 redef class AOnceExpr
1577 redef fun accept_typing
(v
)
1579 self.mtype
= v
.visit_expr
(self.n_expr
)
1583 redef class ASelfExpr
1584 redef var its_variable
: nullable Variable
1585 redef fun accept_typing
(v
)
1587 if v
.is_toplevel_context
and not self isa AImplicitSelfExpr then
1588 v
.error
(self, "Error: `self` cannot be used in top-level method.")
1590 var variable
= v
.selfvariable
1591 self.its_variable
= variable
1592 self.mtype
= v
.get_variable
(self, variable
)
1596 redef class AImplicitSelfExpr
1597 # Is the implicit receiver `sys`?
1599 # By default, the implicit receiver is `self`.
1600 # But when there is not method for `self`, `sys` is used as a fall-back.
1601 # Is this case this flag is set to `true`.
1605 ## MESSAGE SENDING AND PROPERTY
1607 redef class ASendExpr
1608 # The property invoked by the send.
1609 var callsite
: nullable CallSite
1611 redef fun accept_typing
(v
)
1613 var nrecv
= self.n_expr
1614 var recvtype
= v
.visit_expr
(nrecv
)
1615 var name
= self.property_name
1616 var node
= self.property_node
1618 if recvtype
== null then return # Forward error
1621 var unsafe_type
= v
.anchor_to
(recvtype
)
1622 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
1623 if mproperty
== null and nrecv
isa AImplicitSelfExpr then
1624 # Special fall-back search in `sys` when noting found in the implicit receiver.
1625 var sysclass
= v
.try_get_mclass
(node
, "Sys")
1626 if sysclass
!= null then
1627 var systype
= sysclass
.mclass_type
1628 mproperty
= v
.try_get_mproperty_by_name2
(node
, systype
, name
)
1629 if mproperty
!= null then
1630 callsite
= v
.get_method
(node
, systype
, name
, false)
1631 if callsite
== null then return # Forward error
1632 # Update information, we are looking at `sys` now, not `self`
1634 nrecv
.its_variable
= null
1635 nrecv
.mtype
= systype
1640 if callsite
== null then
1641 # If still nothing, just exit
1642 callsite
= v
.get_method
(node
, recvtype
, name
, nrecv
isa ASelfExpr)
1643 if callsite
== null then return
1646 self.callsite
= callsite
1647 var msignature
= callsite
.msignature
1649 var args
= compute_raw_arguments
1651 callsite
.check_signature
(v
, args
)
1653 if callsite
.mproperty
.is_init
then
1654 var vmpropdef
= v
.mpropdef
1655 if not (vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_init
) then
1656 v
.error
(node
, "Error: an `init` can only be called from another `init`.")
1658 if vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_root_init
and not callsite
.mproperty
.is_root_init
then
1659 v
.error
(node
, "Error: `{vmpropdef}` cannot call a factory `{callsite.mproperty}`.")
1663 var ret
= msignature
.return_mtype
1667 self.is_typed
= true
1671 # The name of the property
1672 # Each subclass simply provide the correct name.
1673 private fun property_name
: String is abstract
1675 # The node identifying the name (id, operator, etc) for messages.
1677 # Is `self` by default
1678 private fun property_node
: ANode do return self
1680 # An array of all arguments (excluding self)
1681 fun raw_arguments
: Array[AExpr] do return compute_raw_arguments
1683 private fun compute_raw_arguments
: Array[AExpr] is abstract
1686 redef class ABinopExpr
1687 redef fun compute_raw_arguments
do return [n_expr2
]
1688 redef fun property_name
do return operator
1689 redef fun property_node
do return n_op
1692 redef fun accept_typing
(v
)
1699 redef fun accept_typing
(v
)
1706 redef class AUnaryopExpr
1707 redef fun property_name
do return "unary {operator}"
1708 redef fun compute_raw_arguments
do return new Array[AExpr]
1712 redef class ACallExpr
1713 redef fun property_name
do return n_id
.text
1714 redef fun property_node
do return n_id
1715 redef fun compute_raw_arguments
do return n_args
.to_a
1718 redef class ACallAssignExpr
1719 redef fun property_name
do return n_id
.text
+ "="
1720 redef fun property_node
do return n_id
1721 redef fun compute_raw_arguments
1723 var res
= n_args
.to_a
1729 redef class ABraExpr
1730 redef fun property_name
do return "[]"
1731 redef fun compute_raw_arguments
do return n_args
.to_a
1734 redef class ABraAssignExpr
1735 redef fun property_name
do return "[]="
1736 redef fun compute_raw_arguments
1738 var res
= n_args
.to_a
1744 redef class ASendReassignFormExpr
1745 # The property invoked for the writing
1746 var write_callsite
: nullable CallSite
1748 redef fun accept_typing
(v
)
1750 var recvtype
= v
.visit_expr
(self.n_expr
)
1751 var name
= self.property_name
1752 var node
= self.property_node
1754 if recvtype
== null then return # Forward error
1756 var for_self
= self.n_expr
isa ASelfExpr
1757 var callsite
= v
.get_method
(node
, recvtype
, name
, for_self
)
1759 if callsite
== null then return
1760 self.callsite
= callsite
1762 var args
= compute_raw_arguments
1764 callsite
.check_signature
(v
, args
)
1766 var readtype
= callsite
.msignature
.return_mtype
1767 if readtype
== null then
1768 v
.error
(node
, "Error: `{name}` is not a function.")
1772 var wcallsite
= v
.get_method
(node
, recvtype
, name
+ "=", self.n_expr
isa ASelfExpr)
1773 if wcallsite
== null then return
1774 self.write_callsite
= wcallsite
1776 var wtype
= self.resolve_reassignment
(v
, readtype
, wcallsite
.msignature
.mparameters
.last
.mtype
)
1777 if wtype
== null then return
1779 args
= args
.to_a
# duplicate so raw_arguments keeps only the getter args
1780 args
.add
(self.n_value
)
1781 wcallsite
.check_signature
(v
, args
)
1783 self.is_typed
= true
1787 redef class ACallReassignExpr
1788 redef fun property_name
do return n_id
.text
1789 redef fun property_node
do return n_id
1790 redef fun compute_raw_arguments
do return n_args
.to_a
1793 redef class ABraReassignExpr
1794 redef fun property_name
do return "[]"
1795 redef fun compute_raw_arguments
do return n_args
.to_a
1798 redef class AInitExpr
1799 redef fun property_name
do return "init"
1800 redef fun property_node
do return n_kwinit
1801 redef fun compute_raw_arguments
do return n_args
.to_a
1805 fun to_a
: Array[AExpr] do return self.n_exprs
.to_a
1810 redef class ASuperExpr
1811 # The method to call if the super is in fact a 'super init call'
1812 # Note: if the super is a normal call-next-method, then this attribute is null
1813 var callsite
: nullable CallSite
1815 # The method to call is the super is a standard `call-next-method` super-call
1816 # Note: if the super is a special super-init-call, then this attribute is null
1817 var mpropdef
: nullable MMethodDef
1819 redef fun accept_typing
(v
)
1821 var anchor
= v
.anchor
1822 assert anchor
!= null
1823 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1824 assert recvtype
!= null
1825 var mproperty
= v
.mpropdef
.mproperty
1826 if not mproperty
isa MMethod then
1827 v
.error
(self, "Error: `super` only usable in a `method`.")
1830 var superprops
= mproperty
.lookup_super_definitions
(v
.mmodule
, anchor
)
1831 if superprops
.length
== 0 then
1832 if mproperty
.is_init
and v
.mpropdef
.is_intro
then
1833 process_superinit
(v
)
1836 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1839 # FIXME: covariance of return type in linear extension?
1840 var superprop
= superprops
.first
1842 var msignature
= superprop
.msignature
.as(not null)
1843 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1844 var args
= self.n_args
.to_a
1845 if args
.length
> 0 then
1846 signaturemap
= v
.check_signature
(self, args
, mproperty
, msignature
)
1848 self.mtype
= msignature
.return_mtype
1849 self.is_typed
= true
1850 v
.mpropdef
.has_supercall
= true
1851 mpropdef
= v
.mpropdef
.as(MMethodDef)
1854 # The mapping used on the call to associate arguments to parameters.
1855 # If null then no specific association is required.
1856 var signaturemap
: nullable SignatureMap
1858 private fun process_superinit
(v
: TypeVisitor)
1860 var anchor
= v
.anchor
1861 assert anchor
!= null
1862 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1863 assert recvtype
!= null
1864 var mpropdef
= v
.mpropdef
1865 assert mpropdef
isa MMethodDef
1866 var mproperty
= mpropdef
.mproperty
1867 var superprop
: nullable MMethodDef = null
1868 for msupertype
in mpropdef
.mclassdef
.supertypes
do
1869 msupertype
= msupertype
.anchor_to
(v
.mmodule
, anchor
)
1870 var errcount
= v
.modelbuilder
.toolcontext
.error_count
1871 var candidate
= v
.try_get_mproperty_by_name2
(self, msupertype
, mproperty
.name
).as(nullable MMethod)
1872 if candidate
== null then
1873 if v
.modelbuilder
.toolcontext
.error_count
> errcount
then return # Forward error
1874 continue # Try next super-class
1876 if superprop
!= null and candidate
.is_root_init
then
1879 if superprop
!= null and superprop
.mproperty
!= candidate
and not superprop
.mproperty
.is_root_init
then
1880 v
.error
(self, "Error: conflicting super constructor to call for `{mproperty}`: `{candidate.full_name}`, `{superprop.mproperty.full_name}`")
1883 var candidatedefs
= candidate
.lookup_definitions
(v
.mmodule
, anchor
)
1884 if superprop
!= null and superprop
.mproperty
== candidate
then
1885 if superprop
== candidatedefs
.first
then continue
1886 candidatedefs
.add
(superprop
)
1888 if candidatedefs
.length
> 1 then
1889 v
.error
(self, "Error: conflicting property definitions for property `{mproperty}` in `{recvtype}`: {candidatedefs.join(", ")}")
1892 superprop
= candidatedefs
.first
1894 if superprop
== null then
1895 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1899 var msignature
= superprop
.new_msignature
or else superprop
.msignature
.as(not null)
1900 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1902 var callsite
= new CallSite(self, recvtype
, v
.mmodule
, v
.anchor
, true, superprop
.mproperty
, superprop
, msignature
, false)
1903 self.callsite
= callsite
1905 var args
= self.n_args
.to_a
1906 if args
.length
> 0 then
1907 callsite
.check_signature
(v
, args
)
1909 # Check there is at least enough parameters
1910 if mpropdef
.msignature
.arity
< msignature
.arity
then
1911 v
.error
(self, "Error: not enough implicit arguments to pass. Got `{mpropdef.msignature.arity}`, expected at least `{msignature.arity}`. Signature is `{msignature}`.")
1914 # Check that each needed parameter is conform
1916 for sp
in msignature
.mparameters
do
1917 var p
= mpropdef
.msignature
.mparameters
[i
]
1918 if not v
.is_subtype
(p
.mtype
, sp
.mtype
) then
1919 v
.error
(self, "Type Error: expected argument #{i} of type `{sp.mtype}`, got implicit argument `{p.name}` of type `{p.mtype}`. Signature is {msignature}")
1926 self.is_typed
= true
1932 redef class ANewExpr
1933 # The constructor invoked by the new.
1934 var callsite
: nullable CallSite
1936 # The designated type
1937 var recvtype
: nullable MClassType
1939 redef fun accept_typing
(v
)
1941 var recvtype
= v
.resolve_mtype
(self.n_type
)
1942 if recvtype
== null then return
1944 if not recvtype
isa MClassType then
1945 if recvtype
isa MNullableType then
1946 v
.error
(self, "Type Error: cannot instantiate the nullable type `{recvtype}`.")
1948 else if recvtype
isa MFormalType then
1949 v
.error
(self, "Type Error: cannot instantiate the formal type `{recvtype}`.")
1952 v
.error
(self, "Type Error: cannot instantiate the type `{recvtype}`.")
1957 self.recvtype
= recvtype
1958 var kind
= recvtype
.mclass
.kind
1970 if name
== "intern" then
1971 if kind
!= concrete_kind
then
1972 v
.error
(self, "Type Error: cannot instantiate {kind} {recvtype}.")
1975 if n_args
.n_exprs
.not_empty
then
1976 v
.error
(n_args
, "Type Error: the intern constructor expects no arguments.")
1980 self.mtype
= recvtype
1984 var callsite
= v
.get_method
(node
, recvtype
, name
, false)
1985 if callsite
== null then return
1987 if not callsite
.mproperty
.is_new
then
1988 if kind
!= concrete_kind
then
1989 v
.error
(self, "Type Error: cannot instantiate {kind} `{recvtype}`.")
1992 self.mtype
= recvtype
1994 self.mtype
= callsite
.msignature
.return_mtype
1995 assert self.mtype
!= null
1998 self.callsite
= callsite
2000 if not callsite
.mproperty
.is_init_for
(recvtype
.mclass
) then
2001 v
.error
(self, "Error: `{name}` is not a constructor.")
2005 var args
= n_args
.to_a
2006 callsite
.check_signature
(v
, args
)
2012 redef class AAttrFormExpr
2013 # The attribute accessed.
2014 var mproperty
: nullable MAttribute
2016 # The static type of the attribute.
2017 var attr_type
: nullable MType
2019 # Resolve the attribute accessed.
2020 private fun resolve_property
(v
: TypeVisitor)
2022 var recvtype
= v
.visit_expr
(self.n_expr
)
2023 if recvtype
== null then return # Skip error
2024 var node
= self.n_id
2025 var name
= node
.text
2026 if recvtype
isa MNullType then
2027 v
.error
(node
, "Error: attribute `{name}` access on `null`.")
2031 var unsafe_type
= v
.anchor_to
(recvtype
)
2032 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
2033 if mproperty
== null then
2034 v
.modelbuilder
.error
(node
, "Error: attribute `{name}` does not exist in `{recvtype}`.")
2037 assert mproperty
isa MAttribute
2038 self.mproperty
= mproperty
2040 var mpropdefs
= mproperty
.lookup_definitions
(v
.mmodule
, unsafe_type
)
2041 assert mpropdefs
.length
== 1
2042 var mpropdef
= mpropdefs
.first
2043 var attr_type
= mpropdef
.static_mtype
2044 if attr_type
== null then return # skip error
2045 attr_type
= v
.resolve_for
(attr_type
, recvtype
, self.n_expr
isa ASelfExpr)
2046 self.attr_type
= attr_type
2050 redef class AAttrExpr
2051 redef fun accept_typing
(v
)
2053 self.resolve_property
(v
)
2054 self.mtype
= self.attr_type
2059 redef class AAttrAssignExpr
2060 redef fun accept_typing
(v
)
2062 self.resolve_property
(v
)
2063 var mtype
= self.attr_type
2065 v
.visit_expr_subtype
(self.n_value
, mtype
)
2066 self.is_typed
= mtype
!= null
2070 redef class AAttrReassignExpr
2071 redef fun accept_typing
(v
)
2073 self.resolve_property
(v
)
2074 var mtype
= self.attr_type
2075 if mtype
== null then return # Skip error
2077 var rettype
= self.resolve_reassignment
(v
, mtype
, mtype
)
2079 self.is_typed
= rettype
!= null
2083 redef class AIssetAttrExpr
2084 redef fun accept_typing
(v
)
2086 self.resolve_property
(v
)
2087 var mtype
= self.attr_type
2088 if mtype
== null then return # Skip error
2090 var recvtype
= self.n_expr
.mtype
.as(not null)
2091 var bound
= v
.resolve_for
(mtype
, recvtype
, false)
2092 if bound
isa MNullableType then
2093 v
.error
(n_id
, "Type Error: `isset` on a nullable attribute.")
2095 self.mtype
= v
.type_bool
(self)
2099 redef class AVarargExpr
2100 redef fun accept_typing
(v
)
2102 # This kind of pseudo-expression can be only processed trough a signature
2103 # See `check_signature`
2104 # Other cases are a syntax error.
2105 v
.error
(self, "Syntax Error: unexpected `...`.")
2111 redef class ADebugTypeExpr
2112 redef fun accept_typing
(v
)
2114 var expr
= v
.visit_expr
(self.n_expr
)
2115 if expr
== null then return
2116 var unsafe
= v
.anchor_to
(expr
)
2117 var ntype
= self.n_type
2118 var mtype
= v
.resolve_mtype
(ntype
)
2119 if mtype
!= null and mtype
!= expr
then
2120 var umtype
= v
.anchor_to
(mtype
)
2121 v
.modelbuilder
.warning
(self, "debug", "Found type {expr} (-> {unsafe}), expected {mtype} (-> {umtype})")
2123 self.is_typed
= true