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.
25 redef class ToolContext
26 var typing_phase
: Phase = new TypingPhase(self, [flow_phase
, modelize_property_phase
, local_var_init_phase
])
29 private class TypingPhase
31 redef fun process_npropdef
(npropdef
) do npropdef
.do_typing
(toolcontext
.modelbuilder
)
34 private class TypeVisitor
35 var modelbuilder
: ModelBuilder
37 # The module of the analysis
38 # Used to correctly query the model
41 # The static type of the receiver
42 # Mainly used for type tests and type resolutions
43 var anchor
: nullable MClassType = null
45 # The analyzed mclassdef
46 var mclassdef
: nullable MClassDef = null
48 # The analyzed property
49 var mpropdef
: nullable MPropDef
51 var selfvariable
= new Variable("self")
53 # Is `self` use restricted?
54 # * no explicit `self`
55 # * method called on the implicit self must be top-level
56 # Currently only used for `new` factory since there is no valid receiver inside
57 var is_toplevel_context
= false
61 var mpropdef
= self.mpropdef
63 if mpropdef
!= null then
64 self.mpropdef
= mpropdef
65 var mclassdef
= mpropdef
.mclassdef
66 self.mclassdef
= mclassdef
67 self.anchor
= mclassdef
.bound_mtype
69 var mclass
= mclassdef
.mclass
71 var selfvariable
= new Variable("self")
72 self.selfvariable
= selfvariable
73 selfvariable
.declared_type
= mclass
.mclass_type
75 var mprop
= mpropdef
.mproperty
76 if mprop
isa MMethod and mprop
.is_new
then
77 is_toplevel_context
= true
82 fun anchor_to
(mtype
: MType): MType
85 if anchor
== null then
86 assert not mtype
.need_anchor
89 return mtype
.anchor_to
(mmodule
, anchor
)
92 fun is_subtype
(sub
, sup
: MType): Bool
94 return sub
.is_subtype
(mmodule
, anchor
, sup
)
97 fun resolve_for
(mtype
, subtype
: MType, for_self
: Bool): MType
99 #print "resolve_for {mtype} sub={subtype} forself={for_self} mmodule={mmodule} anchor={anchor}"
100 var res
= mtype
.resolve_for
(subtype
, anchor
, mmodule
, not for_self
)
104 # Check that `sub` is a subtype of `sup`.
105 # If `sub` is not a valid suptype, then display an error on `node` an return null.
106 # If `sub` is a safe subtype of `sup` then return `sub`.
107 # If `sub` is an unsafe subtype (ie an implicit cast is required), then return `sup`.
109 # The point of the return type is to determinate the usable type on an expression when `autocast` is true:
110 # If the suptype is safe, then the return type is the one on the expression typed by `sub`.
111 # Is the subtype is unsafe, then the return type is the one of an implicit cast on `sup`.
112 fun check_subtype
(node
: ANode, sub
, sup
: MType, autocast
: Bool): nullable MType
114 if self.is_subtype
(sub
, sup
) then return sub
115 if autocast
and self.is_subtype
(sub
, self.anchor_to
(sup
)) then
116 # FIXME workaround to the current unsafe typing policy. To remove once fixed virtual types exists.
117 #node.debug("Unsafe typing: expected {sup}, got {sub}")
120 if sup
isa MBottomType then return null # Skip error
121 if sub
.need_anchor
then
122 var u
= anchor_to
(sub
)
123 self.modelbuilder
.error
(node
, "Type Error: expected `{sup}`, got `{sub}: {u}`.")
125 self.modelbuilder
.error
(node
, "Type Error: expected `{sup}`, got `{sub}`.")
130 # Visit an expression and do not care about the return value
131 fun visit_stmt
(nexpr
: nullable AExpr)
133 if nexpr
== null then return
134 nexpr
.accept_typing
(self)
137 # Visit an expression and expects that it is not a statement
138 # Return the type of the expression
139 # Display an error and return null if:
140 # * the type cannot be determined or
141 # * `nexpr` is a statement
142 fun visit_expr
(nexpr
: AExpr): nullable MType
144 nexpr
.accept_typing
(self)
145 var mtype
= nexpr
.mtype
146 if mtype
!= null then return mtype
147 if not nexpr
.is_typed
then
148 if not self.modelbuilder
.toolcontext
.error_count
> 0 then # check that there is really an error
149 if self.modelbuilder
.toolcontext
.verbose_level
> 1 then
150 nexpr
.debug
("No return type but no error.")
153 return null # forward error
155 self.error
(nexpr
, "Error: expected an expression.")
159 # Visit an expression and expect its static type is a least a `sup`
160 # Return the type of the expression or null if
161 # * the type cannot be determined or
162 # * `nexpr` is a statement or
163 # * `nexpr` is not a `sup`
164 fun visit_expr_subtype
(nexpr
: AExpr, sup
: nullable MType): nullable MType
166 var sub
= visit_expr
(nexpr
)
167 if sub
== null then return null # Forward error
169 if sup
== null then return null # Forward error
171 var res
= check_subtype
(nexpr
, sub
, sup
, true)
173 nexpr
.implicit_cast_to
= res
178 # Visit an expression and expect its static type is a `Bool`
179 # Return the type of the expression or null if
180 # * the type cannot be determined or
181 # * `nexpr` is a statement or
182 # * `nexpr` is not a `Bool`
183 fun visit_expr_bool
(nexpr
: AExpr): nullable MType
185 return self.visit_expr_subtype
(nexpr
, self.type_bool
(nexpr
))
189 fun check_expr_cast
(node
: ANode, nexpr
: AExpr, ntype
: AType): nullable MType
191 var sub
= nexpr
.mtype
192 if sub
== null then return null # Forward error
194 var sup
= ntype
.mtype
195 if sup
== null then return null # Forward error
198 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}`.")
199 else if self.is_subtype
(sub
, sup
) then
200 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}` since it is a `{sub}`.")
205 # Can `mtype` be null (up to the current knowledge)?
206 fun can_be_null
(mtype
: MType): Bool
208 if mtype
isa MNullableType or mtype
isa MNullType then return true
209 if mtype
isa MFormalType then
210 var x
= anchor_to
(mtype
)
211 if x
isa MNullableType or x
isa MNullType then return true
216 # Check that `mtype` can be null (up to the current knowledge).
218 # If not then display a `useless-null-test` warning on node and return false.
220 fun check_can_be_null
(anode
: ANode, mtype
: MType): Bool
222 if mtype
isa MNullType then
223 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is always `null`.")
226 if can_be_null
(mtype
) then return true
228 if mtype
isa MFormalType then
229 var res
= anchor_to
(mtype
)
230 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}: {res}`.")
232 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}`.")
237 # Special verification on != and == for null
239 fun null_test
(anode
: ABinopExpr)
241 var mtype
= anode
.n_expr
.mtype
242 var mtype2
= anode
.n_expr2
.mtype
244 if mtype
== null or mtype2
== null then return
246 if not mtype2
isa MNullType then return
248 # Check of useless null
249 if not can_be_null
(mtype
) then return
251 if mtype
isa MNullType then
252 # Because of type adaptation, we cannot just stop here
253 # so return use `null` as a bottom type that will be merged easily (cf) `merge_types`
256 mtype
= mtype
.as_notnull
259 # Check for type adaptation
260 var variable
= anode
.n_expr
.its_variable
261 if variable
== null then return
263 # One is null (mtype2 see above) the other is not null
264 if anode
isa AEqExpr then
265 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype2
)
266 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype
)
267 else if anode
isa ANeExpr then
268 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype2
)
269 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype
)
275 fun try_get_mproperty_by_name2
(anode
: ANode, mtype
: MType, name
: String): nullable MProperty
277 return self.modelbuilder
.try_get_mproperty_by_name2
(anode
, mmodule
, mtype
, name
)
280 fun resolve_mtype
(node
: AType): nullable MType
282 return self.modelbuilder
.resolve_mtype
(mmodule
, mclassdef
, node
)
285 fun try_get_mclass
(node
: ANode, name
: String): nullable MClass
287 var mclass
= modelbuilder
.try_get_mclass_by_name
(node
, mmodule
, name
)
291 fun get_mclass
(node
: ANode, name
: String): nullable MClass
293 var mclass
= modelbuilder
.get_mclass_by_name
(node
, mmodule
, name
)
297 fun type_bool
(node
: ANode): nullable MType
299 var mclass
= self.get_mclass
(node
, "Bool")
300 if mclass
== null then return null
301 return mclass
.mclass_type
304 fun get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
306 var unsafe_type
= self.anchor_to
(recvtype
)
308 #debug("recv: {recvtype} (aka {unsafe_type})")
309 if recvtype
isa MNullType then
310 var objclass
= get_mclass
(node
, "Object")
311 if objclass
== null then return null # Forward error
312 unsafe_type
= objclass
.mclass_type
315 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
316 if name
== "new" and mproperty
== null then
318 mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
321 if mproperty
== null then
323 self.modelbuilder
.error
(node
, "Error: method or variable `{name}` unknown in `{recvtype}`.")
324 else if recvtype
.need_anchor
then
325 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}: {unsafe_type}`.")
327 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}`.")
332 assert mproperty
isa MMethod
334 # `null` only accepts some methods of object.
335 if recvtype
isa MNullType and not mproperty
.is_null_safe
then
336 self.error
(node
, "Error: method `{name}` called on `null`.")
338 else if unsafe_type
isa MNullableType and not mproperty
.is_null_safe
then
339 modelbuilder
.advice
(node
, "call-on-nullable", "Warning: method call on a nullable receiver `{recvtype}`.")
342 if is_toplevel_context
and recv_is_self
and not mproperty
.is_toplevel
then
343 error
(node
, "Error: `{name}` is not a top-level method, thus need a receiver.")
345 if not recv_is_self
and mproperty
.is_toplevel
then
346 error
(node
, "Error: cannot call `{name}`, a top-level method, with a receiver.")
349 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
350 self.modelbuilder
.error
(node
, "Error: method `{name}` is protected and can only accessed by `self`.")
354 var info
= mproperty
.deprecation
355 if info
!= null and self.mpropdef
.mproperty
.deprecation
== null then
358 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated: {mdoc.content.first}")
360 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated.")
364 var propdefs
= mproperty
.lookup_definitions
(self.mmodule
, unsafe_type
)
366 if propdefs
.length
== 0 then
367 self.modelbuilder
.error
(node
, "Type Error: no definition found for property `{name}` in `{unsafe_type}`.")
369 else if propdefs
.length
== 1 then
370 mpropdef
= propdefs
.first
372 self.modelbuilder
.warning
(node
, "property-conflict", "Warning: conflicting property definitions for property `{name}` in `{unsafe_type}`: {propdefs.join(" ")}")
373 mpropdef
= mproperty
.intro
377 var msignature
= mpropdef
.new_msignature
or else mpropdef
.msignature
378 if msignature
== null then return null # skip error
379 msignature
= resolve_for
(msignature
, recvtype
, recv_is_self
).as(MSignature)
381 var erasure_cast
= false
382 var rettype
= mpropdef
.msignature
.return_mtype
383 if not recv_is_self
and rettype
!= null then
384 rettype
= rettype
.undecorate
385 if rettype
isa MParameterType then
386 var erased_rettype
= msignature
.return_mtype
387 assert erased_rettype
!= null
388 #node.debug("Erasure cast: Really a {rettype} but unsafely a {erased_rettype}")
393 var callsite
= new CallSite(node
.hot_location
, recvtype
, mmodule
, anchor
, recv_is_self
, mproperty
, mpropdef
, msignature
, erasure_cast
)
397 fun try_get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
399 var unsafe_type
= self.anchor_to
(recvtype
)
400 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
401 if mproperty
== null then return null
402 return get_method
(node
, recvtype
, name
, recv_is_self
)
406 # Visit the expressions of args and check their conformity with the corresponding type in signature
407 # The point of this method is to handle varargs correctly
408 # Note: The signature must be correctly adapted
409 fun check_signature
(node
: ANode, args
: Array[AExpr], mproperty
: MProperty, msignature
: MSignature): nullable SignatureMap
411 var vararg_rank
= msignature
.vararg_rank
412 if vararg_rank
>= 0 then
413 if args
.length
< msignature
.arity
then
414 modelbuilder
.error
(node
, "Error: expected at least {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
417 else if args
.length
!= msignature
.arity
then
419 if args
.length
> msignature
.arity
then
420 modelbuilder
.error
(node
, "Error: expected {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
423 # Other cases are managed later
427 #debug("CALL {unsafe_type}.{msignature}")
429 # Associate each parameter to a position in the arguments
430 var map
= new SignatureMap
432 # Special case for the isolated last argument
433 # TODO: reify this method characteristics (where? the param, the signature, the method?)
434 var last_is_padded
= mproperty
.name
.chars
.last
== '='
435 var nbargs
= args
.length
436 if last_is_padded
then
438 assert not args
.last
isa ANamedargExpr
439 map
.map
[msignature
.arity
- 1] = args
.length
- 1
440 self.visit_expr_subtype
(args
.last
, msignature
.mparameters
.last
.mtype
)
443 # First, handle named arguments
444 for i
in [0..args
.length
[ do
446 if not e
isa ANamedargExpr then continue
447 var name
= e
.n_id
.text
448 var param
= msignature
.mparameter_by_name
(name
)
449 if param
== null then
450 modelbuilder
.error
(e
.n_id
, "Error: no parameter `{name}` for `{mproperty}{msignature}`.")
453 var idx
= msignature
.mparameters
.index_of
(param
)
454 var prev
= map
.map
.get_or_null
(idx
)
456 modelbuilder
.error
(e
, "Error: parameter `{name}` already associated with argument #{prev} for `{mproperty}{msignature}`.")
460 e
.mtype
= self.visit_expr_subtype
(e
.n_expr
, param
.mtype
)
463 # Number of minimum mandatory remaining parameters
466 # Second, associate remaining parameters
467 var vararg_decl
= args
.length
- msignature
.arity
469 for i
in [0..msignature
.arity
[ do
470 # Skip parameters associated by name
471 if map
.map
.has_key
(i
) then continue
473 var param
= msignature
.mparameters
[i
]
475 # Search the next free argument: skip named arguments since they are already associated
476 while j
< nbargs
and args
[j
] isa ANamedargExpr do j
+= 1
478 if not param
.mtype
isa MNullableType then
488 if i
== vararg_rank
then
490 continue # skip the vararg
493 var paramtype
= param
.mtype
494 self.visit_expr_subtype
(arg
, paramtype
)
497 if min_arity
> 0 then
498 if last_is_padded
then min_arity
+= 1
499 if min_arity
< msignature
.arity
then
500 modelbuilder
.error
(node
, "Error: expected at least {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
502 modelbuilder
.error
(node
, "Error: expected {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
507 # Third, check varargs
508 if vararg_rank
>= 0 then
509 var paramtype
= msignature
.mparameters
[vararg_rank
].mtype
510 var first
= args
[vararg_rank
]
511 if vararg_decl
== 0 then
512 if not check_one_vararg
(first
, msignature
.mparameters
[vararg_rank
]) then return null
514 first
.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 # Check an expression as a single vararg.
525 # The main point of the method if to handle the case of reversed vararg (see `AVarargExpr`)
526 fun check_one_vararg
(arg
: AExpr, param
: MParameter): Bool
528 var paramtype
= param
.mtype
529 var mclass
= get_mclass
(arg
, "Array")
530 if mclass
== null then return false # Forward error
531 var array_mtype
= mclass
.get_mtype
([paramtype
])
532 if arg
isa AVarargExpr then
533 self.visit_expr_subtype
(arg
.n_expr
, array_mtype
)
534 arg
.mtype
= arg
.n_expr
.mtype
536 # only one vararg, maybe `...` was forgot, so be gentle!
537 var t
= visit_expr
(arg
)
538 if t
== null then return false # Forward error
539 if not is_subtype
(t
, paramtype
) and is_subtype
(t
, array_mtype
) then
540 # Not acceptable but could be a `...`
541 error
(arg
, "Type Error: expected `{paramtype}`, got `{t}`. Is an ellipsis `...` missing on the argument?")
544 # Standard valid vararg, finish the job
546 self.visit_expr_subtype
(arg
, paramtype
)
551 fun error
(node
: ANode, message
: String)
553 self.modelbuilder
.error
(node
, message
)
556 fun get_variable
(node
: AExpr, variable
: Variable): nullable MType
558 if not variable
.is_adapted
then return variable
.declared_type
560 var flow
= node
.after_flow_context
561 if flow
== null then return null # skip error
563 if flow
.vars
.has_key
(variable
) then
564 return flow
.vars
[variable
]
566 #node.debug("*** START Collected for {variable}")
567 var mtypes
= flow
.collect_types
(variable
)
568 #node.debug("**** END Collected for {variable}")
569 if mtypes
.length
== 0 then
570 return variable
.declared_type
571 else if mtypes
.length
== 1 then
574 var res
= merge_types
(node
,mtypes
)
575 if res
== null then res
= variable
.declared_type
581 # Some variables where type-adapted during the visit
584 # Some loops had been visited during the visit
587 fun set_variable
(node
: AExpr, variable
: Variable, mtype
: nullable MType)
589 var flow
= node
.after_flow_context
592 flow
.set_var
(self, variable
, mtype
)
595 fun merge_types
(node
: ANode, col
: Array[nullable MType]): nullable MType
597 if col
.length
== 1 then return col
.first
599 if t1
== null then continue # return null
602 if t2
== null then continue # return null
603 if can_be_null
(t2
) and not can_be_null
(t1
) then
606 if not is_subtype
(t2
, t1
) then found
= false
609 #print "merge {col.join(" ")} -> {t1}"
613 #self.modelbuilder.warning(node, "Type Error: {col.length} conflicting types: <{col.join(", ")}>")
618 # Mapping between parameters and arguments in a call.
620 # Parameters and arguments are not stored in the class but referenced by their position (starting from 0)
622 # The point of this class is to help engine and other things to map arguments in the AST to parameters of the model.
624 # Associate a parameter to an argument
625 var map
= new ArrayMap[Int, Int]
628 # A specific method call site with its associated informations.
632 # The associated location of the callsite
633 var location
: Location
635 # The static type of the receiver (possibly unresolved)
638 # The module where the callsite is present
641 # The anchor to use with `recv` or `msignature`
642 var anchor
: nullable MClassType
644 # Is the receiver self?
645 # If "for_self", virtual types of the signature are kept
646 # If "not_for_self", virtual type are erased
647 var recv_is_self
: Bool
649 # The designated method
650 var mproperty
: MMethod
652 # The statically designated method definition
653 # The most specif one, it is.
654 var mpropdef
: MMethodDef
656 # The resolved signature for the receiver
657 var msignature
: MSignature
659 # Is a implicit cast required on erasure typing policy?
660 var erasure_cast
: Bool
662 # The mapping used on the call to associate arguments to parameters
663 # If null then no specific association is required.
664 var signaturemap
: nullable SignatureMap = null
666 private fun check_signature
(v
: TypeVisitor, node
: ANode, args
: Array[AExpr]): Bool
668 var map
= v
.check_signature
(node
, args
, self.mproperty
, self.msignature
)
670 if map
== null then is_broken
= true
676 # The declared type of the variable
677 var declared_type
: nullable MType is writable
679 # Was the variable type-adapted?
680 # This is used to speedup type retrieval while it remains `false`
681 private var is_adapted
= false
684 redef class FlowContext
685 # Store changes of types because of type evolution
686 private var vars
= new HashMap[Variable, nullable MType]
688 # Adapt the variable to a static type
689 # Warning1: do not modify vars directly.
690 # Warning2: sub-flow may have cached a unadapted variable
691 private fun set_var
(v
: TypeVisitor, variable
: Variable, mtype
: nullable MType)
693 if variable
.declared_type
== mtype
and not variable
.is_adapted
then return
694 if vars
.has_key
(variable
) and vars
[variable
] == mtype
then return
695 self.vars
[variable
] = mtype
697 variable
.is_adapted
= true
698 #node.debug "set {variable} to {mtype or else "X"}"
701 # Look in the flow and previous flow and collect all first reachable type adaptation of a local variable
702 private fun collect_types
(variable
: Variable): Array[nullable MType]
704 #node.debug "flow for {variable}"
705 var res
= new Array[nullable MType]
708 var seen
= new HashSet[FlowContext]
709 while not todo
.is_empty
do
711 if f
.is_unreachable
then continue
712 if seen
.has
(f
) then continue
715 if f
.vars
.has_key
(variable
) then
716 # Found something. Collect it and do not process further on this path
717 res
.add f
.vars
[variable
]
718 #f.node.debug "process {variable}: got {f.vars[variable] or else "X"}"
720 todo
.add_all f
.previous
722 if f
.previous
.is_empty
then
723 # Root flowcontext mean a parameter or something related
724 res
.add variable
.declared_type
725 #f.node.debug "root process {variable}: got {variable.declared_type or else "X"}"
729 #self.node.debug "##### end flow for {variable}: {res.join(" ")}"
735 # The entry point of the whole typing analysis
736 fun do_typing
(modelbuilder
: ModelBuilder)
740 # The variable associated to the receiver (if any)
741 var selfvariable
: nullable Variable
744 redef class AMethPropdef
745 redef fun do_typing
(modelbuilder
: ModelBuilder)
747 var mpropdef
= self.mpropdef
748 if mpropdef
== null then return # skip error
750 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
751 self.selfvariable
= v
.selfvariable
753 var mmethoddef
= self.mpropdef
.as(not null)
754 var msignature
= mmethoddef
.msignature
755 if msignature
== null then return # skip error
756 for i
in [0..msignature
.arity
[ do
757 var mtype
= msignature
.mparameters
[i
].mtype
758 if msignature
.vararg_rank
== i
then
759 var arrayclass
= v
.get_mclass
(self.n_signature
.n_params
[i
], "Array")
760 if arrayclass
== null then return # Skip error
761 mtype
= arrayclass
.get_mtype
([mtype
])
763 var variable
= self.n_signature
.n_params
[i
].variable
764 assert variable
!= null
765 variable
.declared_type
= mtype
768 var nblock
= self.n_block
769 if nblock
== null then return
774 if not v
.has_loop
or not v
.dirty
then break
777 var post_visitor
= new PostTypingVisitor(v
)
778 post_visitor
.enter_visit
(self)
780 if not nblock
.after_flow_context
.is_unreachable
and msignature
.return_mtype
!= null then
781 # We reach the end of the function without having a return, it is bad
782 v
.error
(self, "Error: reached end of function; expected `return` with a value.")
787 private class PostTypingVisitor
789 var type_visitor
: TypeVisitor
790 redef fun visit
(n
) do
792 n
.accept_post_typing
(type_visitor
)
793 if n
isa AExpr and n
.mtype
== null and not n
.is_typed
then
800 private fun accept_post_typing
(v
: TypeVisitor) do end
803 redef class AAttrPropdef
804 redef fun do_typing
(modelbuilder
: ModelBuilder)
806 if not has_value
then return
808 var mpropdef
= self.mreadpropdef
809 if mpropdef
== null or mpropdef
.msignature
== null then return # skip error
811 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
812 self.selfvariable
= v
.selfvariable
814 var nexpr
= self.n_expr
815 if nexpr
!= null then
816 var mtype
= self.mtype
817 v
.visit_expr_subtype
(nexpr
, mtype
)
819 var nblock
= self.n_block
820 if nblock
!= null then
822 if not nblock
.after_flow_context
.is_unreachable
then
823 # We reach the end of the init without having a return, it is bad
824 v
.error
(self, "Error: reached end of block; expected `return`.")
833 # The static type of the expression.
834 # null if self is a statement or in case of error
835 var mtype
: nullable MType = null
837 # Is the statement correctly typed?
838 # Used to distinguish errors and statements when `mtype == null`
839 var is_typed
: Bool = false
841 # If required, the following implicit cast `.as(XXX)`
842 # Such a cast may by required after evaluating the expression when
843 # a unsafe operation is detected (silently accepted by the Nit language).
844 # The attribute is computed by `check_subtype`
845 var implicit_cast_to
: nullable MType = null
847 # Return the variable read (if any)
848 # Used to perform adaptive typing
849 fun its_variable
: nullable Variable do return null
851 private fun accept_typing
(v
: TypeVisitor)
853 v
.error
(self, "no implemented accept_typing for {self.class_name}")
856 # Is non-null if `self` is a leaf of a comprehension array construction.
857 # In this case, the enclosing literal array node is designated.
858 # The result of the evaluation of `self` must be
859 # stored inside the designated array (there is an implicit `push`)
860 var comprehension
: nullable AArrayExpr = null
862 # It indicates the number of arguments collected as a vararg.
864 # When 0, the argument is used as is, without transformation.
865 # When 1, the argument is transformed into an singleton array.
866 # Above 1, the arguments and the next ones are transformed into a common array.
868 # This attribute is meaning less on expressions not used as attributes.
869 var vararg_decl
: Int = 0
872 redef class ABlockExpr
873 redef fun accept_typing
(v
)
875 for e
in self.n_expr
do v
.visit_stmt
(e
)
879 # The type of a blockexpr is the one of the last expression (or null if empty)
882 if self.n_expr
.is_empty
then return null
883 return self.n_expr
.last
.mtype
887 redef class AVardeclExpr
888 redef fun accept_typing
(v
)
890 var variable
= self.variable
891 if variable
== null then return # Skip error
893 var ntype
= self.n_type
894 var mtype
: nullable MType
895 if ntype
== null then
898 mtype
= v
.resolve_mtype
(ntype
)
899 if mtype
== null then return # Skip error
902 var nexpr
= self.n_expr
903 if nexpr
!= null then
904 if mtype
!= null then
905 var etype
= v
.visit_expr_subtype
(nexpr
, mtype
)
906 if etype
== mtype
then
908 v
.modelbuilder
.advice
(ntype
, "useless-type", "Warning: useless type definition for variable `{variable.name}`")
911 mtype
= v
.visit_expr
(nexpr
)
912 if mtype
== null then return # Skip error
917 if mtype
== null or mtype
isa MNullType then
918 var objclass
= v
.get_mclass
(self, "Object")
919 if objclass
== null then return # skip error
920 decltype
= objclass
.mclass_type
.as_nullable
921 if mtype
== null then mtype
= decltype
924 variable
.declared_type
= decltype
925 v
.set_variable
(self, variable
, mtype
)
927 #debug("var {variable}: {mtype}")
935 redef fun its_variable
do return self.variable
936 redef fun accept_typing
(v
)
938 var variable
= self.variable
939 if variable
== null then return # Skip error
941 var mtype
= v
.get_variable
(self, variable
)
942 if mtype
!= null then
943 #debug("{variable} is {mtype}")
945 #debug("{variable} is untyped")
952 redef class AVarAssignExpr
953 redef fun accept_typing
(v
)
955 var variable
= self.variable
956 assert variable
!= null
958 var mtype
= v
.visit_expr_subtype
(n_value
, variable
.declared_type
)
960 v
.set_variable
(self, variable
, mtype
)
966 redef class AReassignFormExpr
967 # The method designed by the reassign operator.
968 var reassign_callsite
: nullable CallSite
970 var read_type
: nullable MType = null
972 # Determine the `reassign_property`
973 # `readtype` is the type of the reading of the left value.
974 # `writetype` is the type of the writing of the left value.
975 # (Because of `ACallReassignExpr`, both can be different.
976 # Return the static type of the value to store.
977 private fun resolve_reassignment
(v
: TypeVisitor, readtype
, writetype
: MType): nullable MType
979 var reassign_name
= self.n_assign_op
.operator
981 self.read_type
= readtype
983 var callsite
= v
.get_method
(self.n_assign_op
, readtype
, reassign_name
, false)
984 if callsite
== null then return null # Skip error
985 self.reassign_callsite
= callsite
987 var msignature
= callsite
.msignature
988 var rettype
= msignature
.return_mtype
989 assert msignature
.arity
== 1 and rettype
!= null
991 var value_type
= v
.visit_expr_subtype
(self.n_value
, msignature
.mparameters
.first
.mtype
)
992 if value_type
== null then return null # Skip error
994 v
.check_subtype
(self, rettype
, writetype
, false)
999 redef class AVarReassignExpr
1000 redef fun accept_typing
(v
)
1002 var variable
= self.variable
1003 assert variable
!= null
1005 var readtype
= v
.get_variable
(self, variable
)
1006 if readtype
== null then return
1008 read_type
= readtype
1010 var writetype
= variable
.declared_type
1011 if writetype
== null then return
1013 var rettype
= self.resolve_reassignment
(v
, readtype
, writetype
)
1015 v
.set_variable
(self, variable
, rettype
)
1017 self.is_typed
= rettype
!= null
1022 redef class AContinueExpr
1023 redef fun accept_typing
(v
)
1025 var nexpr
= self.n_expr
1026 if nexpr
!= null then
1029 self.is_typed
= true
1033 redef class ABreakExpr
1034 redef fun accept_typing
(v
)
1036 var nexpr
= self.n_expr
1037 if nexpr
!= null then
1040 self.is_typed
= true
1044 redef class AReturnExpr
1045 redef fun accept_typing
(v
)
1047 var nexpr
= self.n_expr
1049 var mpropdef
= v
.mpropdef
1050 if mpropdef
isa MMethodDef then
1051 ret_type
= mpropdef
.msignature
.return_mtype
1052 else if mpropdef
isa MAttributeDef then
1053 ret_type
= mpropdef
.static_mtype
1057 if nexpr
!= null then
1058 if ret_type
!= null then
1059 v
.visit_expr_subtype
(nexpr
, ret_type
)
1062 v
.error
(nexpr
, "Error: `return` with value in a procedure.")
1065 else if ret_type
!= null then
1066 v
.error
(self, "Error: `return` without value in a function.")
1069 self.is_typed
= true
1073 redef class AAbortExpr
1074 redef fun accept_typing
(v
)
1076 self.is_typed
= true
1081 redef fun accept_typing
(v
)
1083 v
.visit_expr_bool
(n_expr
)
1085 v
.visit_stmt
(n_then
)
1086 v
.visit_stmt
(n_else
)
1088 self.is_typed
= true
1090 if n_then
!= null and n_else
== null then
1091 self.mtype
= n_then
.mtype
1096 redef class AIfexprExpr
1097 redef fun accept_typing
(v
)
1099 v
.visit_expr_bool
(n_expr
)
1101 var t1
= v
.visit_expr
(n_then
)
1102 var t2
= v
.visit_expr
(n_else
)
1104 if t1
== null or t2
== null then
1108 var t
= v
.merge_types
(self, [t1
, t2
])
1110 v
.error
(self, "Type Error: ambiguous type `{t1}` vs `{t2}`.")
1117 redef fun accept_typing
(v
)
1119 v
.visit_stmt
(n_block
)
1120 self.is_typed
= true
1124 redef class AWhileExpr
1125 redef fun accept_typing
(v
)
1128 v
.visit_expr_bool
(n_expr
)
1129 v
.visit_stmt
(n_block
)
1130 self.is_typed
= true
1134 redef class ALoopExpr
1135 redef fun accept_typing
(v
)
1138 v
.visit_stmt
(n_block
)
1139 self.is_typed
= true
1143 redef class AForExpr
1144 redef fun accept_typing
(v
)
1148 for g
in n_groups
do
1149 var mtype
= v
.visit_expr
(g
.n_expr
)
1150 if mtype
== null then return
1151 g
.do_type_iterator
(v
, mtype
)
1152 if g
.is_broken
then is_broken
= true
1155 v
.visit_stmt
(n_block
)
1157 self.mtype
= n_block
.mtype
1158 self.is_typed
= true
1162 redef class AForGroup
1163 var coltype
: nullable MClassType
1165 var method_iterator
: nullable CallSite
1166 var method_is_ok
: nullable CallSite
1167 var method_item
: nullable CallSite
1168 var method_next
: nullable CallSite
1169 var method_key
: nullable CallSite
1170 var method_finish
: nullable CallSite
1172 var method_lt
: nullable CallSite
1173 var method_successor
: nullable CallSite
1175 private fun do_type_iterator
(v
: TypeVisitor, mtype
: MType)
1177 if mtype
isa MNullType then
1178 v
.error
(self, "Type Error: `for` cannot iterate over `null`.")
1183 var objcla
= v
.get_mclass
(self, "Object")
1184 if objcla
== null then return
1186 # check iterator method
1187 var itdef
= v
.get_method
(self, mtype
, "iterator", n_expr
isa ASelfExpr)
1188 if itdef
== null then
1189 v
.error
(self, "Type Error: `for` expects a type providing an `iterator` method, got `{mtype}`.")
1192 self.method_iterator
= itdef
1194 # check that iterator return something
1195 var ittype
= itdef
.msignature
.return_mtype
1196 if ittype
== null then
1197 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1202 var colit_cla
= v
.try_get_mclass
(self, "Iterator")
1203 var mapit_cla
= v
.try_get_mclass
(self, "MapIterator")
1207 if colit_cla
!= null and v
.is_subtype
(ittype
, colit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
])) then
1209 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, colit_cla
)
1210 var variables
= self.variables
1211 if variables
.length
!= 1 then
1212 v
.error
(self, "Type Error: `for` expects only one variable when using `Iterator`.")
1214 variables
.first
.declared_type
= coltype
.arguments
.first
1219 if mapit_cla
!= null and v
.is_subtype
(ittype
, mapit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
, objcla
.mclass_type
.as_nullable
])) then
1221 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, mapit_cla
)
1222 var variables
= self.variables
1223 if variables
.length
!= 2 then
1224 v
.error
(self, "Type Error: `for` expects two variables when using `MapIterator`.")
1226 variables
[0].declared_type
= coltype
.arguments
[0]
1227 variables
[1].declared_type
= coltype
.arguments
[1]
1232 if not is_col
and not is_map
then
1233 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1237 # anchor formal and virtual types
1238 if mtype
.need_anchor
then mtype
= v
.anchor_to
(mtype
)
1240 mtype
= mtype
.undecorate
1241 self.coltype
= mtype
.as(MClassType)
1243 # get methods is_ok, next, item
1244 var ikdef
= v
.get_method
(self, ittype
, "is_ok", false)
1245 if ikdef
== null then
1246 v
.error
(self, "Type Error: `for` expects a method `is_ok` in type `{ittype}`.")
1249 self.method_is_ok
= ikdef
1251 var itemdef
= v
.get_method
(self, ittype
, "item", false)
1252 if itemdef
== null then
1253 v
.error
(self, "Type Error: `for` expects a method `item` in type `{ittype}`.")
1256 self.method_item
= itemdef
1258 var nextdef
= v
.get_method
(self, ittype
, "next", false)
1259 if nextdef
== null then
1260 v
.error
(self, "Type Error: `for` expects a method `next` in type {ittype}.")
1263 self.method_next
= nextdef
1265 self.method_finish
= v
.try_get_method
(self, ittype
, "finish", false)
1268 var keydef
= v
.get_method
(self, ittype
, "key", false)
1269 if keydef
== null then
1270 v
.error
(self, "Type Error: `for` expects a method `key` in type `{ittype}`.")
1273 self.method_key
= keydef
1276 if self.variables
.length
== 1 and n_expr
isa ARangeExpr then
1277 var variable
= variables
.first
1278 var vtype
= variable
.declared_type
.as(not null)
1280 if n_expr
isa AOrangeExpr then
1281 self.method_lt
= v
.get_method
(self, vtype
, "<", false)
1283 self.method_lt
= v
.get_method
(self, vtype
, "<=", false)
1286 self.method_successor
= v
.get_method
(self, vtype
, "successor", false)
1291 redef class AWithExpr
1292 var method_start
: nullable CallSite
1293 var method_finish
: nullable CallSite
1295 redef fun accept_typing
(v
: TypeVisitor)
1297 var mtype
= v
.visit_expr
(n_expr
)
1298 if mtype
== null then return
1300 method_start
= v
.get_method
(self, mtype
, "start", n_expr
isa ASelfExpr)
1301 method_finish
= v
.get_method
(self, mtype
, "finish", n_expr
isa ASelfExpr)
1303 v
.visit_stmt
(n_block
)
1304 self.mtype
= n_block
.mtype
1305 self.is_typed
= true
1309 redef class AAssertExpr
1310 redef fun accept_typing
(v
)
1312 v
.visit_expr_bool
(n_expr
)
1314 v
.visit_stmt
(n_else
)
1315 self.is_typed
= true
1320 redef fun accept_typing
(v
)
1322 v
.visit_expr_bool
(n_expr
)
1323 v
.visit_expr_bool
(n_expr2
)
1324 self.mtype
= v
.type_bool
(self)
1328 redef class AImpliesExpr
1329 redef fun accept_typing
(v
)
1331 v
.visit_expr_bool
(n_expr
)
1332 v
.visit_expr_bool
(n_expr2
)
1333 self.mtype
= v
.type_bool
(self)
1337 redef class AAndExpr
1338 redef fun accept_typing
(v
)
1340 v
.visit_expr_bool
(n_expr
)
1341 v
.visit_expr_bool
(n_expr2
)
1342 self.mtype
= v
.type_bool
(self)
1347 redef class ANotExpr
1348 redef fun accept_typing
(v
)
1350 v
.visit_expr_bool
(n_expr
)
1351 self.mtype
= v
.type_bool
(self)
1355 redef class AOrElseExpr
1356 redef fun accept_typing
(v
)
1358 var t1
= v
.visit_expr
(n_expr
)
1359 var t2
= v
.visit_expr
(n_expr2
)
1361 if t1
== null or t2
== null then
1365 if t1
isa MNullType then
1368 else if v
.can_be_null
(t1
) then
1372 var t
= v
.merge_types
(self, [t1
, t2
])
1374 var c
= v
.get_mclass
(self, "Object")
1375 if c
== null then return # forward error
1377 if v
.can_be_null
(t2
) then
1380 #v.error(self, "Type Error: ambiguous type {t1} vs {t2}")
1385 redef fun accept_post_typing
(v
)
1387 var t1
= n_expr
.mtype
1391 v
.check_can_be_null
(n_expr
, t1
)
1396 redef class ATrueExpr
1397 redef fun accept_typing
(v
)
1399 self.mtype
= v
.type_bool
(self)
1403 redef class AFalseExpr
1404 redef fun accept_typing
(v
)
1406 self.mtype
= v
.type_bool
(self)
1410 redef class AIntegerExpr
1411 redef fun accept_typing
(v
)
1413 var mclass
: nullable MClass = null
1414 if value
isa Byte then
1415 mclass
= v
.get_mclass
(self, "Byte")
1416 else if value
isa Int then
1417 mclass
= v
.get_mclass
(self, "Int")
1418 else if value
isa Int8 then
1419 mclass
= v
.get_mclass
(self, "Int8")
1420 else if value
isa Int16 then
1421 mclass
= v
.get_mclass
(self, "Int16")
1422 else if value
isa UInt16 then
1423 mclass
= v
.get_mclass
(self, "UInt16")
1424 else if value
isa Int32 then
1425 mclass
= v
.get_mclass
(self, "Int32")
1426 else if value
isa UInt32 then
1427 mclass
= v
.get_mclass
(self, "UInt32")
1429 if mclass
== null then return # Forward error
1430 self.mtype
= mclass
.mclass_type
1434 redef class AFloatExpr
1435 redef fun accept_typing
(v
)
1437 var mclass
= v
.get_mclass
(self, "Float")
1438 if mclass
== null then return # Forward error
1439 self.mtype
= mclass
.mclass_type
1443 redef class ACharExpr
1444 redef fun accept_typing
(v
)
1446 var mclass
= v
.get_mclass
(self, "Char")
1447 if mclass
== null then return # Forward error
1448 self.mtype
= mclass
.mclass_type
1452 redef class AStringFormExpr
1453 redef fun accept_typing
(v
)
1455 var mclass
= v
.get_mclass
(self, "String")
1456 if mclass
== null then return # Forward error
1457 self.mtype
= mclass
.mclass_type
1461 redef class ASuperstringExpr
1462 redef fun accept_typing
(v
)
1464 var mclass
= v
.get_mclass
(self, "String")
1465 if mclass
== null then return # Forward error
1466 self.mtype
= mclass
.mclass_type
1467 var objclass
= v
.get_mclass
(self, "Object")
1468 if objclass
== null then return # Forward error
1469 var objtype
= objclass
.mclass_type
1470 for nexpr
in self.n_exprs
do
1471 v
.visit_expr_subtype
(nexpr
, objtype
)
1476 redef class AArrayExpr
1477 # The `with_capacity` method on Array
1478 var with_capacity_callsite
: nullable CallSite
1480 # The `push` method on arrays
1481 var push_callsite
: nullable CallSite
1483 # The element of each type
1484 var element_mtype
: nullable MType
1486 # Set that `self` is a part of comprehension array `na`
1487 # If `self` is a `for`, or a `if`, then `set_comprehension` is recursively applied.
1488 private fun set_comprehension
(n
: nullable AExpr)
1492 else if n
isa AForExpr then
1493 set_comprehension
(n
.n_block
)
1494 else if n
isa AIfExpr then
1495 set_comprehension
(n
.n_then
)
1496 set_comprehension
(n
.n_else
)
1499 n
.comprehension
= self
1502 redef fun accept_typing
(v
)
1504 var mtype
: nullable MType = null
1505 var ntype
= self.n_type
1506 if ntype
!= null then
1507 mtype
= v
.resolve_mtype
(ntype
)
1508 if mtype
== null then return # Skip error
1510 var mtypes
= new Array[nullable MType]
1512 for e
in self.n_exprs
do
1513 var t
= v
.visit_expr
(e
)
1517 set_comprehension
(e
)
1518 if mtype
!= null then
1519 if v
.check_subtype
(e
, t
, mtype
, false) == null then return # Forward error
1520 if t
== mtype
then useless
= true
1525 if mtype
== null then
1526 # Ensure monotony for type adaptation on loops
1527 if self.element_mtype
!= null then mtypes
.add
self.element_mtype
1528 mtype
= v
.merge_types
(self, mtypes
)
1530 if mtype
== null or mtype
isa MNullType then
1531 v
.error
(self, "Type Error: ambiguous array type {mtypes.join(" ")}")
1535 assert ntype
!= null
1536 v
.modelbuilder
.warning
(ntype
, "useless-type", "Warning: useless type declaration `{mtype}` in literal Array since it can be inferred from the elements type.")
1539 self.element_mtype
= mtype
1541 var mclass
= v
.get_mclass
(self, "Array")
1542 if mclass
== null then return # Forward error
1543 var array_mtype
= mclass
.get_mtype
([mtype
])
1545 with_capacity_callsite
= v
.get_method
(self, array_mtype
, "with_capacity", false)
1546 push_callsite
= v
.get_method
(self, array_mtype
, "push", false)
1548 self.mtype
= array_mtype
1552 redef class ARangeExpr
1553 var init_callsite
: nullable CallSite
1555 redef fun accept_typing
(v
)
1557 var discrete_class
= v
.get_mclass
(self, "Discrete")
1558 if discrete_class
== null then return # Forward error
1559 var discrete_type
= discrete_class
.intro
.bound_mtype
1560 var t1
= v
.visit_expr_subtype
(self.n_expr
, discrete_type
)
1561 var t2
= v
.visit_expr_subtype
(self.n_expr2
, discrete_type
)
1562 if t1
== null or t2
== null then return
1563 var mclass
= v
.get_mclass
(self, "Range")
1564 if mclass
== null then return # Forward error
1566 if v
.is_subtype
(t1
, t2
) then
1567 mtype
= mclass
.get_mtype
([t2
])
1568 else if v
.is_subtype
(t2
, t1
) then
1569 mtype
= mclass
.get_mtype
([t1
])
1571 v
.error
(self, "Type Error: cannot create range: `{t1}` vs `{t2}`.")
1577 # get the constructor
1579 if self isa ACrangeExpr then
1580 callsite
= v
.get_method
(self, mtype
, "init", false)
1581 else if self isa AOrangeExpr then
1582 callsite
= v
.get_method
(self, mtype
, "without_last", false)
1586 init_callsite
= callsite
1590 redef class ANullExpr
1591 redef fun accept_typing
(v
)
1593 self.mtype
= v
.mmodule
.model
.null_type
1597 redef class AIsaExpr
1598 # The static type to cast to.
1599 # (different from the static type of the expression that is `Bool`).
1600 var cast_type
: nullable MType
1601 redef fun accept_typing
(v
)
1603 v
.visit_expr
(n_expr
)
1605 var mtype
= v
.resolve_mtype
(n_type
)
1607 self.cast_type
= mtype
1609 var variable
= self.n_expr
.its_variable
1610 if variable
!= null then
1611 #var orig = self.n_expr.mtype
1612 #var from = if orig != null then orig.to_s else "invalid"
1613 #var to = if mtype != null then mtype.to_s else "invalid"
1614 #debug("adapt {variable}: {from} -> {to}")
1615 self.after_flow_context
.when_true
.set_var
(v
, variable
, mtype
)
1618 self.mtype
= v
.type_bool
(self)
1621 redef fun accept_post_typing
(v
)
1623 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1627 redef class AAsCastExpr
1628 redef fun accept_typing
(v
)
1630 v
.visit_expr
(n_expr
)
1632 self.mtype
= v
.resolve_mtype
(n_type
)
1635 redef fun accept_post_typing
(v
)
1637 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1641 redef class AAsNotnullExpr
1642 redef fun accept_typing
(v
)
1644 var mtype
= v
.visit_expr
(self.n_expr
)
1645 if mtype
== null then return # Forward error
1647 if mtype
isa MNullType then
1648 v
.error
(self, "Type Error: `as(not null)` on `null`.")
1652 if v
.can_be_null
(mtype
) then
1653 mtype
= mtype
.as_notnull
1659 redef fun accept_post_typing
(v
)
1661 var mtype
= n_expr
.mtype
1662 if mtype
== null then return
1663 v
.check_can_be_null
(n_expr
, mtype
)
1667 redef class AParExpr
1668 redef fun accept_typing
(v
)
1670 self.mtype
= v
.visit_expr
(self.n_expr
)
1674 redef class AOnceExpr
1675 redef fun accept_typing
(v
)
1677 self.mtype
= v
.visit_expr
(self.n_expr
)
1681 redef class ASelfExpr
1682 redef var its_variable
: nullable Variable
1683 redef fun accept_typing
(v
)
1685 if v
.is_toplevel_context
and not self isa AImplicitSelfExpr then
1686 v
.error
(self, "Error: `self` cannot be used in top-level method.")
1688 var variable
= v
.selfvariable
1689 self.its_variable
= variable
1690 self.mtype
= v
.get_variable
(self, variable
)
1694 redef class AImplicitSelfExpr
1695 # Is the implicit receiver `sys`?
1697 # By default, the implicit receiver is `self`.
1698 # But when there is not method for `self`, `sys` is used as a fall-back.
1699 # Is this case this flag is set to `true`.
1703 ## MESSAGE SENDING AND PROPERTY
1705 redef class ASendExpr
1706 # The property invoked by the send.
1707 var callsite
: nullable CallSite
1709 redef fun accept_typing
(v
)
1711 var nrecv
= self.n_expr
1712 var recvtype
= v
.visit_expr
(nrecv
)
1713 var name
= self.property_name
1714 var node
= self.property_node
1716 if recvtype
== null then return # Forward error
1719 var unsafe_type
= v
.anchor_to
(recvtype
)
1720 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
1721 if mproperty
== null and nrecv
isa AImplicitSelfExpr then
1722 # Special fall-back search in `sys` when noting found in the implicit receiver.
1723 var sysclass
= v
.try_get_mclass
(node
, "Sys")
1724 if sysclass
!= null then
1725 var systype
= sysclass
.mclass_type
1726 mproperty
= v
.try_get_mproperty_by_name2
(node
, systype
, name
)
1727 if mproperty
!= null then
1728 callsite
= v
.get_method
(node
, systype
, name
, false)
1729 if callsite
== null then return # Forward error
1730 # Update information, we are looking at `sys` now, not `self`
1732 nrecv
.its_variable
= null
1733 nrecv
.mtype
= systype
1738 if callsite
== null then
1739 # If still nothing, just exit
1740 callsite
= v
.get_method
(node
, recvtype
, name
, nrecv
isa ASelfExpr)
1741 if callsite
== null then return
1744 self.callsite
= callsite
1745 var msignature
= callsite
.msignature
1747 var args
= compute_raw_arguments
1749 callsite
.check_signature
(v
, node
, args
)
1751 if callsite
.mproperty
.is_init
then
1752 var vmpropdef
= v
.mpropdef
1753 if not (vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_init
) then
1754 v
.error
(node
, "Error: an `init` can only be called from another `init`.")
1756 if vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_root_init
and not callsite
.mproperty
.is_root_init
then
1757 v
.error
(node
, "Error: `{vmpropdef}` cannot call a factory `{callsite.mproperty}`.")
1761 var ret
= msignature
.return_mtype
1765 self.is_typed
= true
1769 # The name of the property
1770 # Each subclass simply provide the correct name.
1771 private fun property_name
: String is abstract
1773 # The node identifying the name (id, operator, etc) for messages.
1775 # Is `self` by default
1776 private fun property_node
: ANode do return self
1778 # An array of all arguments (excluding self)
1779 fun raw_arguments
: Array[AExpr] do return compute_raw_arguments
1781 private fun compute_raw_arguments
: Array[AExpr] is abstract
1784 redef class ABinopExpr
1785 redef fun compute_raw_arguments
do return [n_expr2
]
1786 redef fun property_name
do return operator
1787 redef fun property_node
do return n_op
1790 redef class AEqFormExpr
1791 redef fun accept_typing
(v
)
1797 redef fun accept_post_typing
(v
)
1799 var mtype
= n_expr
.mtype
1800 var mtype2
= n_expr2
.mtype
1802 if mtype
== null or mtype2
== null then return
1804 if not mtype2
isa MNullType then return
1806 v
.check_can_be_null
(n_expr
, mtype
)
1810 redef class AUnaryopExpr
1811 redef fun property_name
do return "unary {operator}"
1812 redef fun compute_raw_arguments
do return new Array[AExpr]
1816 redef class ACallExpr
1817 redef fun property_name
do return n_qid
.n_id
.text
1818 redef fun property_node
do return n_qid
1819 redef fun compute_raw_arguments
do return n_args
.to_a
1822 redef class ACallAssignExpr
1823 redef fun property_name
do return n_qid
.n_id
.text
+ "="
1824 redef fun property_node
do return n_qid
1825 redef fun compute_raw_arguments
1827 var res
= n_args
.to_a
1833 redef class ABraExpr
1834 redef fun property_name
do return "[]"
1835 redef fun compute_raw_arguments
do return n_args
.to_a
1838 redef class ABraAssignExpr
1839 redef fun property_name
do return "[]="
1840 redef fun compute_raw_arguments
1842 var res
= n_args
.to_a
1848 redef class ASendReassignFormExpr
1849 # The property invoked for the writing
1850 var write_callsite
: nullable CallSite
1852 redef fun accept_typing
(v
)
1854 var recvtype
= v
.visit_expr
(self.n_expr
)
1855 var name
= self.property_name
1856 var node
= self.property_node
1858 if recvtype
== null then return # Forward error
1860 var for_self
= self.n_expr
isa ASelfExpr
1861 var callsite
= v
.get_method
(node
, recvtype
, name
, for_self
)
1863 if callsite
== null then return
1864 self.callsite
= callsite
1866 var args
= compute_raw_arguments
1868 callsite
.check_signature
(v
, node
, args
)
1870 var readtype
= callsite
.msignature
.return_mtype
1871 if readtype
== null then
1872 v
.error
(node
, "Error: `{name}` is not a function.")
1876 var wcallsite
= v
.get_method
(node
, recvtype
, name
+ "=", self.n_expr
isa ASelfExpr)
1877 if wcallsite
== null then return
1878 self.write_callsite
= wcallsite
1880 var wtype
= self.resolve_reassignment
(v
, readtype
, wcallsite
.msignature
.mparameters
.last
.mtype
)
1881 if wtype
== null then return
1883 args
= args
.to_a
# duplicate so raw_arguments keeps only the getter args
1884 args
.add
(self.n_value
)
1885 wcallsite
.check_signature
(v
, node
, args
)
1887 self.is_typed
= true
1891 redef class ACallReassignExpr
1892 redef fun property_name
do return n_qid
.n_id
.text
1893 redef fun property_node
do return n_qid
.n_id
1894 redef fun compute_raw_arguments
do return n_args
.to_a
1897 redef class ABraReassignExpr
1898 redef fun property_name
do return "[]"
1899 redef fun compute_raw_arguments
do return n_args
.to_a
1902 redef class AInitExpr
1903 redef fun property_name
do return "init"
1904 redef fun property_node
do return n_kwinit
1905 redef fun compute_raw_arguments
do return n_args
.to_a
1909 fun to_a
: Array[AExpr] do return self.n_exprs
.to_a
1914 redef class ASuperExpr
1915 # The method to call if the super is in fact a 'super init call'
1916 # Note: if the super is a normal call-next-method, then this attribute is null
1917 var callsite
: nullable CallSite
1919 # The method to call is the super is a standard `call-next-method` super-call
1920 # Note: if the super is a special super-init-call, then this attribute is null
1921 var mpropdef
: nullable MMethodDef
1923 redef fun accept_typing
(v
)
1925 var anchor
= v
.anchor
1926 assert anchor
!= null
1927 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1928 assert recvtype
!= null
1929 var mproperty
= v
.mpropdef
.mproperty
1930 if not mproperty
isa MMethod then
1931 v
.error
(self, "Error: `super` only usable in a `method`.")
1934 var superprops
= mproperty
.lookup_super_definitions
(v
.mmodule
, anchor
)
1935 if superprops
.length
== 0 then
1936 if mproperty
.is_init
and v
.mpropdef
.is_intro
then
1937 process_superinit
(v
)
1940 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1943 # FIXME: covariance of return type in linear extension?
1944 var superprop
= superprops
.first
1946 var msignature
= superprop
.msignature
.as(not null)
1947 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1948 var args
= self.n_args
.to_a
1949 if args
.length
> 0 then
1950 signaturemap
= v
.check_signature
(self, args
, mproperty
, msignature
)
1952 self.mtype
= msignature
.return_mtype
1953 self.is_typed
= true
1954 v
.mpropdef
.has_supercall
= true
1955 mpropdef
= v
.mpropdef
.as(MMethodDef)
1958 # The mapping used on the call to associate arguments to parameters.
1959 # If null then no specific association is required.
1960 var signaturemap
: nullable SignatureMap
1962 private fun process_superinit
(v
: TypeVisitor)
1964 var anchor
= v
.anchor
1965 assert anchor
!= null
1966 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1967 assert recvtype
!= null
1968 var mpropdef
= v
.mpropdef
1969 assert mpropdef
isa MMethodDef
1970 var mproperty
= mpropdef
.mproperty
1971 var superprop
: nullable MMethodDef = null
1972 for msupertype
in mpropdef
.mclassdef
.supertypes
do
1973 msupertype
= msupertype
.anchor_to
(v
.mmodule
, anchor
)
1974 var errcount
= v
.modelbuilder
.toolcontext
.error_count
1975 var candidate
= v
.try_get_mproperty_by_name2
(self, msupertype
, mproperty
.name
).as(nullable MMethod)
1976 if candidate
== null then
1977 if v
.modelbuilder
.toolcontext
.error_count
> errcount
then return # Forward error
1978 continue # Try next super-class
1980 if superprop
!= null and candidate
.is_root_init
then
1983 if superprop
!= null and superprop
.mproperty
!= candidate
and not superprop
.mproperty
.is_root_init
then
1984 v
.error
(self, "Error: conflicting super constructor to call for `{mproperty}`: `{candidate.full_name}`, `{superprop.mproperty.full_name}`")
1987 var candidatedefs
= candidate
.lookup_definitions
(v
.mmodule
, anchor
)
1988 if superprop
!= null and superprop
.mproperty
== candidate
then
1989 if superprop
== candidatedefs
.first
then continue
1990 candidatedefs
.add
(superprop
)
1992 if candidatedefs
.length
> 1 then
1993 v
.error
(self, "Error: conflicting property definitions for property `{mproperty}` in `{recvtype}`: {candidatedefs.join(", ")}")
1996 superprop
= candidatedefs
.first
1998 if superprop
== null then
1999 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
2003 var msignature
= superprop
.new_msignature
or else superprop
.msignature
.as(not null)
2004 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
2006 var callsite
= new CallSite(hot_location
, recvtype
, v
.mmodule
, v
.anchor
, true, superprop
.mproperty
, superprop
, msignature
, false)
2007 self.callsite
= callsite
2009 var args
= self.n_args
.to_a
2010 if args
.length
> 0 then
2011 callsite
.check_signature
(v
, self, args
)
2013 # Check there is at least enough parameters
2014 if mpropdef
.msignature
.arity
< msignature
.arity
then
2015 v
.error
(self, "Error: not enough implicit arguments to pass. Got `{mpropdef.msignature.arity}`, expected at least `{msignature.arity}`. Signature is `{msignature}`.")
2018 # Check that each needed parameter is conform
2020 for sp
in msignature
.mparameters
do
2021 var p
= mpropdef
.msignature
.mparameters
[i
]
2022 if not v
.is_subtype
(p
.mtype
, sp
.mtype
) then
2023 v
.error
(self, "Type Error: expected argument #{i} of type `{sp.mtype}`, got implicit argument `{p.name}` of type `{p.mtype}`. Signature is {msignature}")
2030 self.is_typed
= true
2036 redef class ANewExpr
2037 # The constructor invoked by the new.
2038 var callsite
: nullable CallSite
2040 # The designated type
2041 var recvtype
: nullable MClassType
2043 redef fun accept_typing
(v
)
2045 var recvtype
= v
.resolve_mtype
(self.n_type
)
2046 if recvtype
== null then return
2048 if not recvtype
isa MClassType then
2049 if recvtype
isa MNullableType then
2050 v
.error
(self, "Type Error: cannot instantiate the nullable type `{recvtype}`.")
2052 else if recvtype
isa MFormalType then
2053 v
.error
(self, "Type Error: cannot instantiate the formal type `{recvtype}`.")
2056 v
.error
(self, "Type Error: cannot instantiate the type `{recvtype}`.")
2061 self.recvtype
= recvtype
2062 var kind
= recvtype
.mclass
.kind
2065 var nqid
= self.n_qid
2067 if nqid
!= null then
2068 name
= nqid
.n_id
.text
2074 if name
== "intern" then
2075 if kind
!= concrete_kind
then
2076 v
.error
(self, "Type Error: cannot instantiate {kind} {recvtype}.")
2079 if n_args
.n_exprs
.not_empty
then
2080 v
.error
(n_args
, "Type Error: the intern constructor expects no arguments.")
2084 self.mtype
= recvtype
2088 var callsite
= v
.get_method
(node
, recvtype
, name
, false)
2089 if callsite
== null then return
2091 if not callsite
.mproperty
.is_new
then
2092 if kind
!= concrete_kind
then
2093 v
.error
(self, "Type Error: cannot instantiate {kind} `{recvtype}`.")
2096 self.mtype
= recvtype
2098 self.mtype
= callsite
.msignature
.return_mtype
2099 assert self.mtype
!= null
2102 self.callsite
= callsite
2104 if not callsite
.mproperty
.is_init_for
(recvtype
.mclass
) then
2105 v
.error
(self, "Error: `{name}` is not a constructor.")
2109 var args
= n_args
.to_a
2110 callsite
.check_signature
(v
, node
, args
)
2116 redef class AAttrFormExpr
2117 # The attribute accessed.
2118 var mproperty
: nullable MAttribute
2120 # The static type of the attribute.
2121 var attr_type
: nullable MType
2123 # Resolve the attribute accessed.
2124 private fun resolve_property
(v
: TypeVisitor)
2126 var recvtype
= v
.visit_expr
(self.n_expr
)
2127 if recvtype
== null then return # Skip error
2128 var node
= self.n_id
2129 var name
= node
.text
2130 if recvtype
isa MNullType then
2131 v
.error
(node
, "Error: attribute `{name}` access on `null`.")
2135 var unsafe_type
= v
.anchor_to
(recvtype
)
2136 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
2137 if mproperty
== null then
2138 v
.modelbuilder
.error
(node
, "Error: attribute `{name}` does not exist in `{recvtype}`.")
2141 assert mproperty
isa MAttribute
2142 self.mproperty
= mproperty
2144 var mpropdefs
= mproperty
.lookup_definitions
(v
.mmodule
, unsafe_type
)
2145 assert mpropdefs
.length
== 1
2146 var mpropdef
= mpropdefs
.first
2147 var attr_type
= mpropdef
.static_mtype
2148 if attr_type
== null then return # skip error
2149 attr_type
= v
.resolve_for
(attr_type
, recvtype
, self.n_expr
isa ASelfExpr)
2150 self.attr_type
= attr_type
2154 redef class AAttrExpr
2155 redef fun accept_typing
(v
)
2157 self.resolve_property
(v
)
2158 self.mtype
= self.attr_type
2163 redef class AAttrAssignExpr
2164 redef fun accept_typing
(v
)
2166 self.resolve_property
(v
)
2167 var mtype
= self.attr_type
2169 v
.visit_expr_subtype
(self.n_value
, mtype
)
2170 self.is_typed
= mtype
!= null
2174 redef class AAttrReassignExpr
2175 redef fun accept_typing
(v
)
2177 self.resolve_property
(v
)
2178 var mtype
= self.attr_type
2179 if mtype
== null then return # Skip error
2181 var rettype
= self.resolve_reassignment
(v
, mtype
, mtype
)
2183 self.is_typed
= rettype
!= null
2187 redef class AIssetAttrExpr
2188 redef fun accept_typing
(v
)
2190 self.resolve_property
(v
)
2191 var mtype
= self.attr_type
2192 if mtype
== null then return # Skip error
2194 var recvtype
= self.n_expr
.mtype
.as(not null)
2195 var bound
= v
.resolve_for
(mtype
, recvtype
, false)
2196 if bound
isa MNullableType then
2197 v
.error
(n_id
, "Type Error: `isset` on a nullable attribute.")
2199 self.mtype
= v
.type_bool
(self)
2203 redef class AVarargExpr
2204 redef fun accept_typing
(v
)
2206 # This kind of pseudo-expression can be only processed trough a signature
2207 # See `check_signature`
2208 # Other cases are a syntax error.
2209 v
.error
(self, "Syntax Error: unexpected `...`.")
2215 redef class ADebugTypeExpr
2216 redef fun accept_typing
(v
)
2218 var expr
= v
.visit_expr
(self.n_expr
)
2219 if expr
== null then return
2220 var unsafe
= v
.anchor_to
(expr
)
2221 var ntype
= self.n_type
2222 var mtype
= v
.resolve_mtype
(ntype
)
2223 if mtype
!= null and mtype
!= expr
then
2224 var umtype
= v
.anchor_to
(mtype
)
2225 v
.modelbuilder
.warning
(self, "debug", "Found type {expr} (-> {unsafe}), expected {mtype} (-> {umtype})")
2227 self.is_typed
= true