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` and return `null`.
106 # If `sub` is a safe subtype of `sup`, then return `sub`.
107 # If `sub` is an unsafe subtype (i.e., 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 MErrorType 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 var more_message
= null
157 if p
!= null then more_message
= p
.bad_expr_message
(nexpr
)
158 if more_message
== null then more_message
= "" else more_message
= " " + more_message
159 self.error
(nexpr
, "Error: expected an expression{more_message}.")
163 # Visit an expression and expect its static type is a least a `sup`
164 # Return the type of the expression or null if
165 # * the type cannot be determined or
166 # * `nexpr` is a statement or
167 # * `nexpr` is not a `sup`
168 fun visit_expr_subtype
(nexpr
: AExpr, sup
: nullable MType): nullable MType
170 var sub
= visit_expr
(nexpr
)
171 if sub
== null then return null # Forward error
173 if sup
== null then return null # Forward error
175 var res
= check_subtype
(nexpr
, sub
, sup
, true)
177 nexpr
.implicit_cast_to
= res
182 # Visit an expression and expect its static type is a `Bool`
183 # Return the type of the expression or null if
184 # * the type cannot be determined or
185 # * `nexpr` is a statement or
186 # * `nexpr` is not a `Bool`
187 fun visit_expr_bool
(nexpr
: AExpr): nullable MType
189 return self.visit_expr_subtype
(nexpr
, self.type_bool
(nexpr
))
193 fun check_expr_cast
(node
: ANode, nexpr
: AExpr, ntype
: AType): nullable MType
195 var sub
= nexpr
.mtype
196 if sub
== null then return null # Forward error
198 var sup
= ntype
.mtype
199 if sup
== null then return null # Forward error
202 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}`.")
203 else if self.is_subtype
(sub
, sup
) then
204 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}` since it is a `{sub}`.")
209 # Can `mtype` be null (up to the current knowledge)?
210 fun can_be_null
(mtype
: MType): Bool
212 if mtype
isa MNullableType or mtype
isa MNullType then return true
213 if mtype
isa MFormalType then
214 var x
= anchor_to
(mtype
)
215 if x
isa MNullableType or x
isa MNullType then return true
220 # Check that `mtype` can be null (up to the current knowledge).
222 # If not then display a `useless-null-test` warning on node and return false.
224 fun check_can_be_null
(anode
: ANode, mtype
: MType): Bool
226 if mtype
isa MNullType then
227 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is always `null`.")
230 if can_be_null
(mtype
) then return true
232 if mtype
isa MFormalType then
233 var res
= anchor_to
(mtype
)
234 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}: {res}`.")
236 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}`.")
241 # Special verification on != and == for null
243 fun null_test
(anode
: ABinopExpr)
245 var mtype
= anode
.n_expr
.mtype
246 var mtype2
= anode
.n_expr2
.mtype
248 if mtype
== null or mtype2
== null then return
250 if not mtype2
isa MNullType then return
252 # Check of useless null
253 if not can_be_null
(mtype
) then return
255 if mtype
isa MNullType then
256 # Because of type adaptation, we cannot just stop here
257 # so return use `null` as a bottom type that will be merged easily (cf) `merge_types`
260 mtype
= mtype
.as_notnull
263 # Check for type adaptation
264 var variable
= anode
.n_expr
.its_variable
265 if variable
== null then return
267 # One is null (mtype2 see above) the other is not null
268 if anode
isa AEqExpr then
269 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype2
)
270 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype
)
271 else if anode
isa ANeExpr then
272 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype2
)
273 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype
)
279 fun try_get_mproperty_by_name2
(anode
: ANode, mtype
: MType, name
: String): nullable MProperty
281 return self.modelbuilder
.try_get_mproperty_by_name2
(anode
, mmodule
, mtype
, name
)
284 fun resolve_mtype
(node
: AType): nullable MType
286 return self.modelbuilder
.resolve_mtype
(mmodule
, mclassdef
, node
)
289 fun try_get_mclass
(node
: ANode, name
: String): nullable MClass
291 var mclass
= modelbuilder
.try_get_mclass_by_name
(node
, mmodule
, name
)
295 fun get_mclass
(node
: ANode, name
: String): nullable MClass
297 var mclass
= modelbuilder
.get_mclass_by_name
(node
, mmodule
, name
)
301 fun type_bool
(node
: ANode): nullable MType
303 var mclass
= self.get_mclass
(node
, "Bool")
304 if mclass
== null then return null
305 return mclass
.mclass_type
308 fun get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
310 var unsafe_type
= self.anchor_to
(recvtype
)
312 #debug("recv: {recvtype} (aka {unsafe_type})")
313 if recvtype
isa MNullType then
314 var objclass
= get_mclass
(node
, "Object")
315 if objclass
== null then return null # Forward error
316 unsafe_type
= objclass
.mclass_type
319 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
320 if name
== "new" and mproperty
== null then
322 mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
325 if mproperty
== null then
327 self.modelbuilder
.error
(node
, "Error: method or variable `{name}` unknown in `{recvtype}`.")
328 else if recvtype
.need_anchor
then
329 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}: {unsafe_type}`.")
331 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}`.")
336 assert mproperty
isa MMethod
338 # `null` only accepts some methods of object.
339 if recvtype
isa MNullType and not mproperty
.is_null_safe
then
340 self.error
(node
, "Error: method `{name}` called on `null`.")
342 else if unsafe_type
isa MNullableType and not mproperty
.is_null_safe
then
343 modelbuilder
.advice
(node
, "call-on-nullable", "Warning: method call on a nullable receiver `{recvtype}`.")
346 if is_toplevel_context
and recv_is_self
and not mproperty
.is_toplevel
then
347 error
(node
, "Error: `{name}` is not a top-level method, thus need a receiver.")
349 if not recv_is_self
and mproperty
.is_toplevel
then
350 error
(node
, "Error: cannot call `{name}`, a top-level method, with a receiver.")
353 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
354 self.modelbuilder
.error
(node
, "Error: method `{name}` is protected and can only accessed by `self`.")
358 var info
= mproperty
.deprecation
359 if info
!= null and self.mpropdef
.mproperty
.deprecation
== null then
362 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated: {mdoc.content.first}")
364 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated.")
368 var propdefs
= mproperty
.lookup_definitions
(self.mmodule
, unsafe_type
)
370 if propdefs
.length
== 0 then
371 self.modelbuilder
.error
(node
, "Type Error: no definition found for property `{name}` in `{unsafe_type}`.")
373 else if propdefs
.length
== 1 then
374 mpropdef
= propdefs
.first
376 self.modelbuilder
.warning
(node
, "property-conflict", "Warning: conflicting property definitions for property `{name}` in `{unsafe_type}`: {propdefs.join(" ")}")
377 mpropdef
= mproperty
.intro
381 var msignature
= mpropdef
.new_msignature
or else mpropdef
.msignature
382 if msignature
== null then return null # skip error
383 msignature
= resolve_for
(msignature
, recvtype
, recv_is_self
).as(MSignature)
385 var erasure_cast
= false
386 var rettype
= mpropdef
.msignature
.return_mtype
387 if not recv_is_self
and rettype
!= null then
388 rettype
= rettype
.undecorate
389 if rettype
isa MParameterType then
390 var erased_rettype
= msignature
.return_mtype
391 assert erased_rettype
!= null
392 #node.debug("Erasure cast: Really a {rettype} but unsafely a {erased_rettype}")
397 var callsite
= new CallSite(node
.hot_location
, recvtype
, mmodule
, anchor
, recv_is_self
, mproperty
, mpropdef
, msignature
, erasure_cast
)
401 fun try_get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
403 var unsafe_type
= self.anchor_to
(recvtype
)
404 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
405 if mproperty
== null then return null
406 return get_method
(node
, recvtype
, name
, recv_is_self
)
410 # Visit the expressions of args and check their conformity with the corresponding type in signature
411 # The point of this method is to handle varargs correctly
412 # Note: The signature must be correctly adapted
413 fun check_signature
(node
: ANode, args
: Array[AExpr], mproperty
: MProperty, msignature
: MSignature): nullable SignatureMap
415 var vararg_rank
= msignature
.vararg_rank
416 if vararg_rank
>= 0 then
417 if args
.length
< msignature
.arity
then
418 modelbuilder
.error
(node
, "Error: expected at least {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
421 else if args
.length
!= msignature
.arity
then
423 if args
.length
> msignature
.arity
then
424 modelbuilder
.error
(node
, "Error: expected {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
427 # Other cases are managed later
431 #debug("CALL {unsafe_type}.{msignature}")
433 # Associate each parameter to a position in the arguments
434 var map
= new SignatureMap
436 # Special case for the isolated last argument
437 # TODO: reify this method characteristics (where? the param, the signature, the method?)
438 var last_is_padded
= mproperty
.name
.chars
.last
== '='
439 var nbargs
= args
.length
440 if last_is_padded
then
442 assert not args
.last
isa ANamedargExpr
443 map
.map
[msignature
.arity
- 1] = args
.length
- 1
444 self.visit_expr_subtype
(args
.last
, msignature
.mparameters
.last
.mtype
)
447 # First, handle named arguments
448 for i
in [0..args
.length
[ do
450 if not e
isa ANamedargExpr then continue
451 var name
= e
.n_id
.text
452 var param
= msignature
.mparameter_by_name
(name
)
453 if param
== null then
454 modelbuilder
.error
(e
.n_id
, "Error: no parameter `{name}` for `{mproperty}{msignature}`.")
457 var idx
= msignature
.mparameters
.index_of
(param
)
458 var prev
= map
.map
.get_or_null
(idx
)
460 modelbuilder
.error
(e
, "Error: parameter `{name}` already associated with argument #{prev} for `{mproperty}{msignature}`.")
464 e
.mtype
= self.visit_expr_subtype
(e
.n_expr
, param
.mtype
)
467 # Number of minimum mandatory remaining parameters
470 # Second, associate remaining parameters
471 var vararg_decl
= args
.length
- msignature
.arity
473 for i
in [0..msignature
.arity
[ do
474 # Skip parameters associated by name
475 if map
.map
.has_key
(i
) then continue
477 var param
= msignature
.mparameters
[i
]
479 # Search the next free argument: skip named arguments since they are already associated
480 while j
< nbargs
and args
[j
] isa ANamedargExpr do j
+= 1
482 if not param
.mtype
isa MNullableType then
492 if i
== vararg_rank
then
494 continue # skip the vararg
497 if not param
.is_vararg
then
498 var paramtype
= param
.mtype
499 self.visit_expr_subtype
(arg
, paramtype
)
501 check_one_vararg
(arg
, param
)
505 if min_arity
> 0 then
506 if last_is_padded
then min_arity
+= 1
507 if min_arity
< msignature
.arity
then
508 modelbuilder
.error
(node
, "Error: expected at least {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
510 modelbuilder
.error
(node
, "Error: expected {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
515 # Third, check varargs
516 if vararg_rank
>= 0 then
517 var paramtype
= msignature
.mparameters
[vararg_rank
].mtype
518 var first
= args
[vararg_rank
]
519 if vararg_decl
== 0 then
520 if not check_one_vararg
(first
, msignature
.mparameters
[vararg_rank
]) then return null
522 first
.vararg_decl
= vararg_decl
+ 1
523 for i
in [vararg_rank
..vararg_rank
+vararg_decl
] do
524 self.visit_expr_subtype
(args
[i
], paramtype
)
532 # Check an expression as a single vararg.
533 # The main point of the method if to handle the case of reversed vararg (see `AVarargExpr`)
534 fun check_one_vararg
(arg
: AExpr, param
: MParameter): Bool
536 var paramtype
= param
.mtype
537 var mclass
= get_mclass
(arg
, "Array")
538 if mclass
== null then return false # Forward error
539 var array_mtype
= mclass
.get_mtype
([paramtype
])
540 if arg
isa AVarargExpr then
541 self.visit_expr_subtype
(arg
.n_expr
, array_mtype
)
542 arg
.mtype
= arg
.n_expr
.mtype
544 # only one vararg, maybe `...` was forgot, so be gentle!
545 var t
= visit_expr
(arg
)
546 if t
== null then return false # Forward error
547 if not is_subtype
(t
, paramtype
) and is_subtype
(t
, array_mtype
) then
548 # Not acceptable but could be a `...`
549 error
(arg
, "Type Error: expected `{paramtype}`, got `{t}`. Is an ellipsis `...` missing on the argument?")
552 # Standard valid vararg, finish the job
554 self.visit_expr_subtype
(arg
, paramtype
)
559 fun error
(node
: ANode, message
: String)
561 self.modelbuilder
.error
(node
, message
)
564 fun get_variable
(node
: AExpr, variable
: Variable): nullable MType
566 if not variable
.is_adapted
then return variable
.declared_type
568 var flow
= node
.after_flow_context
569 if flow
== null then return null # skip error
571 if flow
.vars
.has_key
(variable
) then
572 return flow
.vars
[variable
]
574 #node.debug("*** START Collected for {variable}")
575 var mtypes
= flow
.collect_types
(variable
)
576 #node.debug("**** END Collected for {variable}")
577 if mtypes
.length
== 0 then
578 return variable
.declared_type
579 else if mtypes
.length
== 1 then
582 var res
= merge_types
(node
,mtypes
)
583 if res
== null then res
= variable
.declared_type
589 # Some variables where type-adapted during the visit
592 # Some loops had been visited during the visit
595 fun set_variable
(node
: AExpr, variable
: Variable, mtype
: nullable MType)
597 var flow
= node
.after_flow_context
600 flow
.set_var
(self, variable
, mtype
)
603 fun merge_types
(node
: ANode, col
: Array[nullable MType]): nullable MType
605 if col
.length
== 1 then return col
.first
607 if t1
== null then continue # return null
610 if t2
== null then continue # return null
611 if can_be_null
(t2
) and not can_be_null
(t1
) then
614 if not is_subtype
(t2
, t1
) then found
= false
617 #print "merge {col.join(" ")} -> {t1}"
621 #self.modelbuilder.warning(node, "Type Error: {col.length} conflicting types: <{col.join(", ")}>")
626 # Mapping between parameters and arguments in a call.
628 # Parameters and arguments are not stored in the class but referenced by their position (starting from 0)
630 # The point of this class is to help engine and other things to map arguments in the AST to parameters of the model.
632 # Associate a parameter to an argument
633 var map
= new ArrayMap[Int, Int]
636 # A specific method call site with its associated informations.
640 redef var location
: Location
642 # The static type of the receiver (possibly unresolved)
645 # The module where the callsite is present
648 # The anchor to use with `recv` or `msignature`
649 var anchor
: nullable MClassType
651 # Is the receiver self?
652 # If "for_self", virtual types of the signature are kept
653 # If "not_for_self", virtual type are erased
654 var recv_is_self
: Bool
656 # The designated method
657 var mproperty
: MMethod
659 # The statically designated method definition
660 # The most specif one, it is.
661 var mpropdef
: MMethodDef
663 # The resolved signature for the receiver
664 var msignature
: MSignature
666 # Is a implicit cast required on erasure typing policy?
667 var erasure_cast
: Bool
669 # The mapping used on the call to associate arguments to parameters
670 # If null then no specific association is required.
671 var signaturemap
: nullable SignatureMap = null
673 private fun check_signature
(v
: TypeVisitor, node
: ANode, args
: Array[AExpr]): Bool
675 var map
= v
.check_signature
(node
, args
, self.mproperty
, self.msignature
)
677 if map
== null then is_broken
= true
683 # The declared type of the variable
684 var declared_type
: nullable MType is writable
686 # Was the variable type-adapted?
687 # This is used to speedup type retrieval while it remains `false`
688 private var is_adapted
= false
691 redef class FlowContext
692 # Store changes of types because of type evolution
693 private var vars
= new HashMap[Variable, nullable MType]
695 # Adapt the variable to a static type
696 # Warning1: do not modify vars directly.
697 # Warning2: sub-flow may have cached a unadapted variable
698 private fun set_var
(v
: TypeVisitor, variable
: Variable, mtype
: nullable MType)
700 if variable
.declared_type
== mtype
and not variable
.is_adapted
then return
701 if vars
.has_key
(variable
) and vars
[variable
] == mtype
then return
702 self.vars
[variable
] = mtype
704 variable
.is_adapted
= true
705 #node.debug "set {variable} to {mtype or else "X"}"
708 # Look in the flow and previous flow and collect all first reachable type adaptation of a local variable
709 private fun collect_types
(variable
: Variable): Array[nullable MType]
711 #node.debug "flow for {variable}"
712 var res
= new Array[nullable MType]
715 var seen
= new HashSet[FlowContext]
716 while not todo
.is_empty
do
718 if f
.is_unreachable
then continue
719 if seen
.has
(f
) then continue
722 if f
.vars
.has_key
(variable
) then
723 # Found something. Collect it and do not process further on this path
724 res
.add f
.vars
[variable
]
725 #f.node.debug "process {variable}: got {f.vars[variable] or else "X"}"
727 todo
.add_all f
.previous
729 if f
.previous
.is_empty
then
730 # Root flowcontext mean a parameter or something related
731 res
.add variable
.declared_type
732 #f.node.debug "root process {variable}: got {variable.declared_type or else "X"}"
736 #self.node.debug "##### end flow for {variable}: {res.join(" ")}"
742 # The entry point of the whole typing analysis
743 fun do_typing
(modelbuilder
: ModelBuilder)
747 # The variable associated to the receiver (if any)
748 var selfvariable
: nullable Variable
751 redef class AMethPropdef
752 redef fun do_typing
(modelbuilder
: ModelBuilder)
754 var mpropdef
= self.mpropdef
755 if mpropdef
== null then return # skip error
757 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
758 self.selfvariable
= v
.selfvariable
760 var mmethoddef
= self.mpropdef
.as(not null)
761 var msignature
= mmethoddef
.msignature
762 if msignature
== null then return # skip error
763 for i
in [0..msignature
.arity
[ do
764 var mtype
= msignature
.mparameters
[i
].mtype
765 if msignature
.vararg_rank
== i
then
766 var arrayclass
= v
.get_mclass
(self.n_signature
.n_params
[i
], "Array")
767 if arrayclass
== null then return # Skip error
768 mtype
= arrayclass
.get_mtype
([mtype
])
770 var variable
= self.n_signature
.n_params
[i
].variable
771 assert variable
!= null
772 variable
.declared_type
= mtype
775 var nblock
= self.n_block
776 if nblock
== null then return
781 if not v
.has_loop
or not v
.dirty
then break
784 var post_visitor
= new PostTypingVisitor(v
)
785 post_visitor
.enter_visit
(self)
787 if not nblock
.after_flow_context
.is_unreachable
and msignature
.return_mtype
!= null then
788 # We reach the end of the function without having a return, it is bad
789 v
.error
(self, "Error: reached end of function; expected `return` with a value.")
794 private class PostTypingVisitor
796 var type_visitor
: TypeVisitor
797 redef fun visit
(n
) do
799 n
.accept_post_typing
(type_visitor
)
800 if n
isa AExpr and n
.mtype
== null and not n
.is_typed
then
807 private fun accept_post_typing
(v
: TypeVisitor) do end
809 # An additional information message to explain the role of a child expression.
811 # The point of the method is to allow some kind of double dispatch so the parent
812 # choose how to describe its children.
813 private fun bad_expr_message
(child
: AExpr): nullable String do return null
816 redef class AAttrPropdef
817 redef fun do_typing
(modelbuilder
: ModelBuilder)
819 if not has_value
then return
821 var mpropdef
= self.mreadpropdef
822 if mpropdef
== null or mpropdef
.msignature
== null then return # skip error
824 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
825 self.selfvariable
= v
.selfvariable
827 var nexpr
= self.n_expr
828 if nexpr
!= null then
829 var mtype
= self.mtype
830 v
.visit_expr_subtype
(nexpr
, mtype
)
832 var nblock
= self.n_block
833 if nblock
!= null then
835 if not nblock
.after_flow_context
.is_unreachable
then
836 # We reach the end of the init without having a return, it is bad
837 v
.error
(self, "Error: reached end of block; expected `return`.")
846 # The static type of the expression.
847 # null if self is a statement or in case of error
848 var mtype
: nullable MType = null
850 # Is the statement correctly typed?
851 # Used to distinguish errors and statements when `mtype == null`
852 var is_typed
: Bool = false
854 # If required, the following implicit cast `.as(XXX)`
855 # Such a cast may by required after evaluating the expression when
856 # a unsafe operation is detected (silently accepted by the Nit language).
857 # The attribute is computed by `check_subtype`
858 var implicit_cast_to
: nullable MType = null
860 # Return the variable read (if any)
861 # Used to perform adaptive typing
862 fun its_variable
: nullable Variable do return null
864 private fun accept_typing
(v
: TypeVisitor)
866 v
.error
(self, "no implemented accept_typing for {self.class_name}")
869 # Is non-null if `self` is a leaf of a comprehension array construction.
870 # In this case, the enclosing literal array node is designated.
871 # The result of the evaluation of `self` must be
872 # stored inside the designated array (there is an implicit `push`)
873 var comprehension
: nullable AArrayExpr = null
875 # It indicates the number of arguments collected as a vararg.
877 # When 0, the argument is used as is, without transformation.
878 # When 1, the argument is transformed into an singleton array.
879 # Above 1, the arguments and the next ones are transformed into a common array.
881 # This attribute is meaning less on expressions not used as attributes.
882 var vararg_decl
: Int = 0
885 redef class ABlockExpr
886 redef fun accept_typing
(v
)
888 for e
in self.n_expr
do v
.visit_stmt
(e
)
892 # The type of a blockexpr is the one of the last expression (or null if empty)
895 if self.n_expr
.is_empty
then return null
896 return self.n_expr
.last
.mtype
900 redef class AVardeclExpr
901 redef fun accept_typing
(v
)
903 var variable
= self.variable
904 if variable
== null then return # Skip error
906 var ntype
= self.n_type
907 var mtype
: nullable MType
908 if ntype
== null then
911 mtype
= v
.resolve_mtype
(ntype
)
912 if mtype
== null then return # Skip error
915 var nexpr
= self.n_expr
916 if nexpr
!= null then
917 if mtype
!= null then
918 var etype
= v
.visit_expr_subtype
(nexpr
, mtype
)
919 if etype
== mtype
then
921 v
.modelbuilder
.advice
(ntype
, "useless-type", "Warning: useless type definition for variable `{variable.name}`")
924 mtype
= v
.visit_expr
(nexpr
)
925 if mtype
== null then return # Skip error
930 if mtype
== null or mtype
isa MNullType then
931 var objclass
= v
.get_mclass
(self, "Object")
932 if objclass
== null then return # skip error
933 decltype
= objclass
.mclass_type
.as_nullable
934 if mtype
== null then mtype
= decltype
937 variable
.declared_type
= decltype
938 v
.set_variable
(self, variable
, mtype
)
940 #debug("var {variable}: {mtype}")
948 redef fun its_variable
do return self.variable
949 redef fun accept_typing
(v
)
951 var variable
= self.variable
952 if variable
== null then return # Skip error
954 var mtype
= v
.get_variable
(self, variable
)
955 if mtype
!= null then
956 #debug("{variable} is {mtype}")
958 #debug("{variable} is untyped")
965 redef class AVarAssignExpr
966 redef fun accept_typing
(v
)
968 var variable
= self.variable
969 assert variable
!= null
971 var mtype
= v
.visit_expr_subtype
(n_value
, variable
.declared_type
)
973 v
.set_variable
(self, variable
, mtype
)
979 redef class AReassignFormExpr
980 # The method designed by the reassign operator.
981 var reassign_callsite
: nullable CallSite
983 var read_type
: nullable MType = null
985 # Determine the `reassign_property`
986 # `readtype` is the type of the reading of the left value.
987 # `writetype` is the type of the writing of the left value.
988 # (Because of `ACallReassignExpr`, both can be different.
989 # Return the static type of the value to store.
990 private fun resolve_reassignment
(v
: TypeVisitor, readtype
, writetype
: MType): nullable MType
992 var reassign_name
= self.n_assign_op
.operator
994 self.read_type
= readtype
996 var callsite
= v
.get_method
(self.n_assign_op
, readtype
, reassign_name
, false)
997 if callsite
== null then return null # Skip error
998 self.reassign_callsite
= callsite
1000 var msignature
= callsite
.msignature
1001 var rettype
= msignature
.return_mtype
1002 assert msignature
.arity
== 1 and rettype
!= null
1004 var value_type
= v
.visit_expr_subtype
(self.n_value
, msignature
.mparameters
.first
.mtype
)
1005 if value_type
== null then return null # Skip error
1007 v
.check_subtype
(self, rettype
, writetype
, false)
1012 redef class AVarReassignExpr
1013 redef fun accept_typing
(v
)
1015 var variable
= self.variable
1016 assert variable
!= null
1018 var readtype
= v
.get_variable
(self, variable
)
1019 if readtype
== null then return
1021 read_type
= readtype
1023 var writetype
= variable
.declared_type
1024 if writetype
== null then return
1026 var rettype
= self.resolve_reassignment
(v
, readtype
, writetype
)
1028 v
.set_variable
(self, variable
, rettype
)
1030 self.is_typed
= rettype
!= null
1035 redef class AContinueExpr
1036 redef fun accept_typing
(v
)
1038 var nexpr
= self.n_expr
1039 if nexpr
!= null then
1042 self.is_typed
= true
1046 redef class ABreakExpr
1047 redef fun accept_typing
(v
)
1049 var nexpr
= self.n_expr
1050 if nexpr
!= null then
1053 self.is_typed
= true
1057 redef class AReturnExpr
1058 redef fun accept_typing
(v
)
1060 var nexpr
= self.n_expr
1062 var mpropdef
= v
.mpropdef
1063 if mpropdef
isa MMethodDef then
1064 ret_type
= mpropdef
.msignature
.return_mtype
1065 else if mpropdef
isa MAttributeDef then
1066 ret_type
= mpropdef
.static_mtype
1070 if nexpr
!= null then
1071 if ret_type
!= null then
1072 v
.visit_expr_subtype
(nexpr
, ret_type
)
1075 v
.error
(nexpr
, "Error: `return` with value in a procedure.")
1078 else if ret_type
!= null then
1079 v
.error
(self, "Error: `return` without value in a function.")
1082 self.is_typed
= true
1086 redef class AAbortExpr
1087 redef fun accept_typing
(v
)
1089 self.is_typed
= true
1094 redef fun accept_typing
(v
)
1096 v
.visit_expr_bool
(n_expr
)
1098 v
.visit_stmt
(n_then
)
1099 v
.visit_stmt
(n_else
)
1101 self.is_typed
= true
1103 if n_then
!= null and n_else
== null then
1104 self.mtype
= n_then
.mtype
1109 redef class AIfexprExpr
1110 redef fun accept_typing
(v
)
1112 v
.visit_expr_bool
(n_expr
)
1114 var t1
= v
.visit_expr
(n_then
)
1115 var t2
= v
.visit_expr
(n_else
)
1117 if t1
== null or t2
== null then
1121 var t
= v
.merge_types
(self, [t1
, t2
])
1123 v
.error
(self, "Type Error: ambiguous type `{t1}` vs `{t2}`.")
1130 redef fun accept_typing
(v
)
1132 v
.visit_stmt
(n_block
)
1133 v
.visit_stmt
(n_catch
)
1134 self.is_typed
= true
1138 redef class AWhileExpr
1139 redef fun accept_typing
(v
)
1142 v
.visit_expr_bool
(n_expr
)
1143 v
.visit_stmt
(n_block
)
1144 self.is_typed
= true
1148 redef class ALoopExpr
1149 redef fun accept_typing
(v
)
1152 v
.visit_stmt
(n_block
)
1153 self.is_typed
= true
1157 redef class AForExpr
1158 redef fun accept_typing
(v
)
1162 for g
in n_groups
do
1163 var mtype
= v
.visit_expr
(g
.n_expr
)
1164 if mtype
== null then return
1165 g
.do_type_iterator
(v
, mtype
)
1166 if g
.is_broken
then is_broken
= true
1169 v
.visit_stmt
(n_block
)
1171 self.mtype
= n_block
.mtype
1172 self.is_typed
= true
1176 redef class AForGroup
1177 var coltype
: nullable MClassType
1179 var method_iterator
: nullable CallSite
1180 var method_is_ok
: nullable CallSite
1181 var method_item
: nullable CallSite
1182 var method_next
: nullable CallSite
1183 var method_key
: nullable CallSite
1184 var method_finish
: nullable CallSite
1186 var method_lt
: nullable CallSite
1187 var method_successor
: nullable CallSite
1189 private fun do_type_iterator
(v
: TypeVisitor, mtype
: MType)
1191 if mtype
isa MNullType then
1192 v
.error
(self, "Type Error: `for` cannot iterate over `null`.")
1197 var objcla
= v
.get_mclass
(self, "Object")
1198 if objcla
== null then return
1200 # check iterator method
1201 var itdef
= v
.get_method
(self, mtype
, "iterator", n_expr
isa ASelfExpr)
1202 if itdef
== null then
1203 v
.error
(self, "Type Error: `for` expects a type providing an `iterator` method, got `{mtype}`.")
1206 self.method_iterator
= itdef
1208 # check that iterator return something
1209 var ittype
= itdef
.msignature
.return_mtype
1210 if ittype
== null then
1211 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1216 var colit_cla
= v
.try_get_mclass
(self, "Iterator")
1217 var mapit_cla
= v
.try_get_mclass
(self, "MapIterator")
1221 if colit_cla
!= null and v
.is_subtype
(ittype
, colit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
])) then
1223 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, colit_cla
)
1224 var variables
= self.variables
1225 if variables
.length
!= 1 then
1226 v
.error
(self, "Type Error: `for` expects only one variable when using `Iterator`.")
1228 variables
.first
.declared_type
= coltype
.arguments
.first
1233 if mapit_cla
!= null and v
.is_subtype
(ittype
, mapit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
, objcla
.mclass_type
.as_nullable
])) then
1235 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, mapit_cla
)
1236 var variables
= self.variables
1237 if variables
.length
!= 2 then
1238 v
.error
(self, "Type Error: `for` expects two variables when using `MapIterator`.")
1240 variables
[0].declared_type
= coltype
.arguments
[0]
1241 variables
[1].declared_type
= coltype
.arguments
[1]
1246 if not is_col
and not is_map
then
1247 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1251 # anchor formal and virtual types
1252 if mtype
.need_anchor
then mtype
= v
.anchor_to
(mtype
)
1254 mtype
= mtype
.undecorate
1255 self.coltype
= mtype
.as(MClassType)
1257 # get methods is_ok, next, item
1258 var ikdef
= v
.get_method
(self, ittype
, "is_ok", false)
1259 if ikdef
== null then
1260 v
.error
(self, "Type Error: `for` expects a method `is_ok` in type `{ittype}`.")
1263 self.method_is_ok
= ikdef
1265 var itemdef
= v
.get_method
(self, ittype
, "item", false)
1266 if itemdef
== null then
1267 v
.error
(self, "Type Error: `for` expects a method `item` in type `{ittype}`.")
1270 self.method_item
= itemdef
1272 var nextdef
= v
.get_method
(self, ittype
, "next", false)
1273 if nextdef
== null then
1274 v
.error
(self, "Type Error: `for` expects a method `next` in type {ittype}.")
1277 self.method_next
= nextdef
1279 self.method_finish
= v
.try_get_method
(self, ittype
, "finish", false)
1282 var keydef
= v
.get_method
(self, ittype
, "key", false)
1283 if keydef
== null then
1284 v
.error
(self, "Type Error: `for` expects a method `key` in type `{ittype}`.")
1287 self.method_key
= keydef
1290 if self.variables
.length
== 1 and n_expr
isa ARangeExpr then
1291 var variable
= variables
.first
1292 var vtype
= variable
.declared_type
.as(not null)
1294 if n_expr
isa AOrangeExpr then
1295 self.method_lt
= v
.get_method
(self, vtype
, "<", false)
1297 self.method_lt
= v
.get_method
(self, vtype
, "<=", false)
1300 self.method_successor
= v
.get_method
(self, vtype
, "successor", false)
1305 redef class AWithExpr
1306 var method_start
: nullable CallSite
1307 var method_finish
: nullable CallSite
1309 redef fun accept_typing
(v
: TypeVisitor)
1311 var mtype
= v
.visit_expr
(n_expr
)
1312 if mtype
== null then return
1314 method_start
= v
.get_method
(self, mtype
, "start", n_expr
isa ASelfExpr)
1315 method_finish
= v
.get_method
(self, mtype
, "finish", n_expr
isa ASelfExpr)
1317 v
.visit_stmt
(n_block
)
1318 self.mtype
= n_block
.mtype
1319 self.is_typed
= true
1323 redef class AAssertExpr
1324 redef fun accept_typing
(v
)
1326 v
.visit_expr_bool
(n_expr
)
1328 v
.visit_stmt
(n_else
)
1329 self.is_typed
= true
1334 redef fun accept_typing
(v
)
1336 v
.visit_expr_bool
(n_expr
)
1337 v
.visit_expr_bool
(n_expr2
)
1338 self.mtype
= v
.type_bool
(self)
1342 redef class AImpliesExpr
1343 redef fun accept_typing
(v
)
1345 v
.visit_expr_bool
(n_expr
)
1346 v
.visit_expr_bool
(n_expr2
)
1347 self.mtype
= v
.type_bool
(self)
1351 redef class AAndExpr
1352 redef fun accept_typing
(v
)
1354 v
.visit_expr_bool
(n_expr
)
1355 v
.visit_expr_bool
(n_expr2
)
1356 self.mtype
= v
.type_bool
(self)
1361 redef class ANotExpr
1362 redef fun accept_typing
(v
)
1364 v
.visit_expr_bool
(n_expr
)
1365 self.mtype
= v
.type_bool
(self)
1369 redef class AOrElseExpr
1370 redef fun accept_typing
(v
)
1372 var t1
= v
.visit_expr
(n_expr
)
1373 var t2
= v
.visit_expr
(n_expr2
)
1375 if t1
== null or t2
== null then
1379 if t1
isa MNullType then
1382 else if v
.can_be_null
(t1
) then
1386 var t
= v
.merge_types
(self, [t1
, t2
])
1388 var c
= v
.get_mclass
(self, "Object")
1389 if c
== null then return # forward error
1391 if v
.can_be_null
(t2
) then
1394 #v.error(self, "Type Error: ambiguous type {t1} vs {t2}")
1399 redef fun accept_post_typing
(v
)
1401 var t1
= n_expr
.mtype
1405 v
.check_can_be_null
(n_expr
, t1
)
1410 redef class ATrueExpr
1411 redef fun accept_typing
(v
)
1413 self.mtype
= v
.type_bool
(self)
1417 redef class AFalseExpr
1418 redef fun accept_typing
(v
)
1420 self.mtype
= v
.type_bool
(self)
1424 redef class AIntegerExpr
1425 redef fun accept_typing
(v
)
1427 var mclass
: nullable MClass = null
1428 if value
isa Byte then
1429 mclass
= v
.get_mclass
(self, "Byte")
1430 else if value
isa Int then
1431 mclass
= v
.get_mclass
(self, "Int")
1432 else if value
isa Int8 then
1433 mclass
= v
.get_mclass
(self, "Int8")
1434 else if value
isa Int16 then
1435 mclass
= v
.get_mclass
(self, "Int16")
1436 else if value
isa UInt16 then
1437 mclass
= v
.get_mclass
(self, "UInt16")
1438 else if value
isa Int32 then
1439 mclass
= v
.get_mclass
(self, "Int32")
1440 else if value
isa UInt32 then
1441 mclass
= v
.get_mclass
(self, "UInt32")
1443 if mclass
== null then return # Forward error
1444 self.mtype
= mclass
.mclass_type
1448 redef class AFloatExpr
1449 redef fun accept_typing
(v
)
1451 var mclass
= v
.get_mclass
(self, "Float")
1452 if mclass
== null then return # Forward error
1453 self.mtype
= mclass
.mclass_type
1457 redef class ACharExpr
1458 redef fun accept_typing
(v
) do
1459 var mclass
: nullable MClass = null
1461 mclass
= v
.get_mclass
(self, "Byte")
1462 else if is_code_point
then
1463 mclass
= v
.get_mclass
(self, "Int")
1465 mclass
= v
.get_mclass
(self, "Char")
1467 if mclass
== null then return # Forward error
1468 self.mtype
= mclass
.mclass_type
1472 redef class AugmentedStringFormExpr
1475 # Text::to_re, used for prefix `re`
1476 var to_re
: nullable CallSite = null
1477 # Regex::ignore_case, used for suffix `i` on `re`
1478 var ignore_case
: nullable CallSite = null
1479 # Regex::newline, used for suffix `m` on `re`
1480 var newline
: nullable CallSite = null
1481 # Regex::extended, used for suffix `b` on `re`
1482 var extended
: nullable CallSite = null
1483 # NativeString::to_bytes_with_copy, used for prefix `b`
1484 var to_bytes_with_copy
: nullable CallSite = null
1486 redef fun accept_typing
(v
) do
1487 var mclass
= v
.get_mclass
(self, "String")
1488 if mclass
== null then return # Forward error
1489 if is_bytestring
then
1490 to_bytes_with_copy
= v
.get_method
(self, v
.mmodule
.native_string_type
, "to_bytes_with_copy", false)
1491 mclass
= v
.get_mclass
(self, "Bytes")
1493 to_re
= v
.get_method
(self, mclass
.mclass_type
, "to_re", false)
1494 for i
in suffix
.chars
do
1495 mclass
= v
.get_mclass
(self, "Regex")
1496 if mclass
== null then
1497 v
.error
(self, "Error: `Regex` class unknown")
1502 service
= "ignore_case="
1503 ignore_case
= v
.get_method
(self, mclass
.mclass_type
, service
, false)
1504 else if i
== 'm' then
1505 service
= "newline="
1506 newline
= v
.get_method
(self, mclass
.mclass_type
, service
, false)
1507 else if i
== 'b' then
1508 service
= "extended="
1509 extended
= v
.get_method
(self, mclass
.mclass_type
, service
, false)
1511 v
.error
(self, "Type Error: Unrecognized suffix {i} in prefixed Regex")
1516 if mclass
== null then return # Forward error
1517 mtype
= mclass
.mclass_type
1521 redef class ASuperstringExpr
1522 redef fun accept_typing
(v
)
1525 var objclass
= v
.get_mclass
(self, "Object")
1526 if objclass
== null then return # Forward error
1527 var objtype
= objclass
.mclass_type
1528 for nexpr
in self.n_exprs
do
1529 v
.visit_expr_subtype
(nexpr
, objtype
)
1534 redef class AArrayExpr
1535 # The `with_capacity` method on Array
1536 var with_capacity_callsite
: nullable CallSite
1538 # The `push` method on arrays
1539 var push_callsite
: nullable CallSite
1541 # The element of each type
1542 var element_mtype
: nullable MType
1544 # Set that `self` is a part of comprehension array `na`
1545 # If `self` is a `for`, or a `if`, then `set_comprehension` is recursively applied.
1546 private fun set_comprehension
(n
: nullable AExpr)
1550 else if n
isa AForExpr then
1551 set_comprehension
(n
.n_block
)
1552 else if n
isa AIfExpr then
1553 set_comprehension
(n
.n_then
)
1554 set_comprehension
(n
.n_else
)
1557 n
.comprehension
= self
1560 redef fun accept_typing
(v
)
1562 var mtype
: nullable MType = null
1563 var ntype
= self.n_type
1564 if ntype
!= null then
1565 mtype
= v
.resolve_mtype
(ntype
)
1566 if mtype
== null then return # Skip error
1568 var mtypes
= new Array[nullable MType]
1570 for e
in self.n_exprs
do
1571 var t
= v
.visit_expr
(e
)
1575 set_comprehension
(e
)
1576 if mtype
!= null then
1577 if v
.check_subtype
(e
, t
, mtype
, false) == null then return # Forward error
1578 if t
== mtype
then useless
= true
1583 if mtype
== null then
1584 # Ensure monotony for type adaptation on loops
1585 if self.element_mtype
!= null then mtypes
.add
self.element_mtype
1586 mtype
= v
.merge_types
(self, mtypes
)
1588 if mtype
== null or mtype
isa MNullType then
1589 v
.error
(self, "Type Error: ambiguous array type {mtypes.join(" ")}")
1593 assert ntype
!= null
1594 v
.modelbuilder
.warning
(ntype
, "useless-type", "Warning: useless type declaration `{mtype}` in literal Array since it can be inferred from the elements type.")
1597 self.element_mtype
= mtype
1599 var mclass
= v
.get_mclass
(self, "Array")
1600 if mclass
== null then return # Forward error
1601 var array_mtype
= mclass
.get_mtype
([mtype
])
1603 with_capacity_callsite
= v
.get_method
(self, array_mtype
, "with_capacity", false)
1604 push_callsite
= v
.get_method
(self, array_mtype
, "push", false)
1606 self.mtype
= array_mtype
1610 redef class ARangeExpr
1611 var init_callsite
: nullable CallSite
1613 redef fun accept_typing
(v
)
1615 var discrete_class
= v
.get_mclass
(self, "Discrete")
1616 if discrete_class
== null then return # Forward error
1617 var discrete_type
= discrete_class
.intro
.bound_mtype
1618 var t1
= v
.visit_expr_subtype
(self.n_expr
, discrete_type
)
1619 var t2
= v
.visit_expr_subtype
(self.n_expr2
, discrete_type
)
1620 if t1
== null or t2
== null then return
1621 var mclass
= v
.get_mclass
(self, "Range")
1622 if mclass
== null then return # Forward error
1624 if v
.is_subtype
(t1
, t2
) then
1625 mtype
= mclass
.get_mtype
([t2
])
1626 else if v
.is_subtype
(t2
, t1
) then
1627 mtype
= mclass
.get_mtype
([t1
])
1629 v
.error
(self, "Type Error: cannot create range: `{t1}` vs `{t2}`.")
1635 # get the constructor
1637 if self isa ACrangeExpr then
1638 callsite
= v
.get_method
(self, mtype
, "init", false)
1639 else if self isa AOrangeExpr then
1640 callsite
= v
.get_method
(self, mtype
, "without_last", false)
1644 init_callsite
= callsite
1648 redef class ANullExpr
1649 redef fun accept_typing
(v
)
1651 self.mtype
= v
.mmodule
.model
.null_type
1655 redef class AIsaExpr
1656 # The static type to cast to.
1657 # (different from the static type of the expression that is `Bool`).
1658 var cast_type
: nullable MType
1659 redef fun accept_typing
(v
)
1661 v
.visit_expr
(n_expr
)
1663 var mtype
= v
.resolve_mtype
(n_type
)
1665 self.cast_type
= mtype
1667 var variable
= self.n_expr
.its_variable
1668 if variable
!= null then
1669 var orig
= self.n_expr
.mtype
1670 #var from = if orig != null then orig.to_s else "invalid"
1671 #var to = if mtype != null then mtype.to_s else "invalid"
1672 #debug("adapt {variable}: {from} -> {to}")
1674 # Do not adapt if there is no information gain (i.e. adapt to a supertype)
1675 if mtype
== null or orig
== null or not v
.is_subtype
(orig
, mtype
) then
1676 self.after_flow_context
.when_true
.set_var
(v
, variable
, mtype
)
1680 self.mtype
= v
.type_bool
(self)
1683 redef fun accept_post_typing
(v
)
1685 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1689 redef class AAsCastExpr
1690 redef fun accept_typing
(v
)
1692 v
.visit_expr
(n_expr
)
1694 self.mtype
= v
.resolve_mtype
(n_type
)
1697 redef fun accept_post_typing
(v
)
1699 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1703 redef class AAsNotnullExpr
1704 redef fun accept_typing
(v
)
1706 var mtype
= v
.visit_expr
(self.n_expr
)
1707 if mtype
== null then return # Forward error
1709 if mtype
isa MNullType then
1710 v
.error
(self, "Type Error: `as(not null)` on `null`.")
1714 if v
.can_be_null
(mtype
) then
1715 mtype
= mtype
.as_notnull
1721 redef fun accept_post_typing
(v
)
1723 var mtype
= n_expr
.mtype
1724 if mtype
== null then return
1725 v
.check_can_be_null
(n_expr
, mtype
)
1729 redef class AParExpr
1730 redef fun accept_typing
(v
)
1732 self.mtype
= v
.visit_expr
(self.n_expr
)
1736 redef class AOnceExpr
1737 redef fun accept_typing
(v
)
1739 self.mtype
= v
.visit_expr
(self.n_expr
)
1743 redef class ASelfExpr
1744 redef var its_variable
: nullable Variable
1745 redef fun accept_typing
(v
)
1747 if v
.is_toplevel_context
and not self isa AImplicitSelfExpr then
1748 v
.error
(self, "Error: `self` cannot be used in top-level method.")
1750 var variable
= v
.selfvariable
1751 self.its_variable
= variable
1752 self.mtype
= v
.get_variable
(self, variable
)
1756 redef class AImplicitSelfExpr
1757 # Is the implicit receiver `sys`?
1759 # By default, the implicit receiver is `self`.
1760 # But when there is not method for `self`, `sys` is used as a fall-back.
1761 # Is this case this flag is set to `true`.
1765 ## MESSAGE SENDING AND PROPERTY
1767 redef class ASendExpr
1768 # The property invoked by the send.
1769 var callsite
: nullable CallSite
1771 redef fun bad_expr_message
(child
)
1773 if child
== self.n_expr
then
1774 return "to be the receiver of `{self.property_name}`"
1779 redef fun accept_typing
(v
)
1781 var nrecv
= self.n_expr
1782 var recvtype
= v
.visit_expr
(nrecv
)
1783 var name
= self.property_name
1784 var node
= self.property_node
1786 if recvtype
== null then return # Forward error
1789 var unsafe_type
= v
.anchor_to
(recvtype
)
1790 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
1791 if mproperty
== null and nrecv
isa AImplicitSelfExpr then
1792 # Special fall-back search in `sys` when noting found in the implicit receiver.
1793 var sysclass
= v
.try_get_mclass
(node
, "Sys")
1794 if sysclass
!= null then
1795 var systype
= sysclass
.mclass_type
1796 mproperty
= v
.try_get_mproperty_by_name2
(node
, systype
, name
)
1797 if mproperty
!= null then
1798 callsite
= v
.get_method
(node
, systype
, name
, false)
1799 if callsite
== null then return # Forward error
1800 # Update information, we are looking at `sys` now, not `self`
1802 nrecv
.its_variable
= null
1803 nrecv
.mtype
= systype
1808 if callsite
== null then
1809 # If still nothing, just exit
1810 callsite
= v
.get_method
(node
, recvtype
, name
, nrecv
isa ASelfExpr)
1811 if callsite
== null then return
1814 self.callsite
= callsite
1815 var msignature
= callsite
.msignature
1817 var args
= compute_raw_arguments
1819 callsite
.check_signature
(v
, node
, args
)
1821 if callsite
.mproperty
.is_init
then
1822 var vmpropdef
= v
.mpropdef
1823 if not (vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_init
) then
1824 v
.error
(node
, "Error: an `init` can only be called from another `init`.")
1826 if vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_root_init
and not callsite
.mproperty
.is_root_init
then
1827 v
.error
(node
, "Error: `{vmpropdef}` cannot call a factory `{callsite.mproperty}`.")
1831 var ret
= msignature
.return_mtype
1835 self.is_typed
= true
1839 # The name of the property
1840 # Each subclass simply provide the correct name.
1841 private fun property_name
: String is abstract
1843 # The node identifying the name (id, operator, etc) for messages.
1845 # Is `self` by default
1846 private fun property_node
: ANode do return self
1848 # An array of all arguments (excluding self)
1849 fun raw_arguments
: Array[AExpr] do return compute_raw_arguments
1851 private fun compute_raw_arguments
: Array[AExpr] is abstract
1854 redef class ABinopExpr
1855 redef fun compute_raw_arguments
do return [n_expr2
]
1856 redef fun property_name
do return operator
1857 redef fun property_node
do return n_op
1860 redef class AEqFormExpr
1861 redef fun accept_typing
(v
)
1867 redef fun accept_post_typing
(v
)
1869 var mtype
= n_expr
.mtype
1870 var mtype2
= n_expr2
.mtype
1872 if mtype
== null or mtype2
== null then return
1874 if not mtype2
isa MNullType then return
1876 v
.check_can_be_null
(n_expr
, mtype
)
1880 redef class AUnaryopExpr
1881 redef fun property_name
do return "unary {operator}"
1882 redef fun compute_raw_arguments
do return new Array[AExpr]
1886 redef class ACallExpr
1887 redef fun property_name
do return n_qid
.n_id
.text
1888 redef fun property_node
do return n_qid
1889 redef fun compute_raw_arguments
do return n_args
.to_a
1892 redef class ACallAssignExpr
1893 redef fun property_name
do return n_qid
.n_id
.text
+ "="
1894 redef fun property_node
do return n_qid
1895 redef fun compute_raw_arguments
1897 var res
= n_args
.to_a
1903 redef class ABraExpr
1904 redef fun property_name
do return "[]"
1905 redef fun compute_raw_arguments
do return n_args
.to_a
1908 redef class ABraAssignExpr
1909 redef fun property_name
do return "[]="
1910 redef fun compute_raw_arguments
1912 var res
= n_args
.to_a
1918 redef class ASendReassignFormExpr
1919 # The property invoked for the writing
1920 var write_callsite
: nullable CallSite
1922 redef fun accept_typing
(v
)
1924 var recvtype
= v
.visit_expr
(self.n_expr
)
1925 var name
= self.property_name
1926 var node
= self.property_node
1928 if recvtype
== null then return # Forward error
1930 var for_self
= self.n_expr
isa ASelfExpr
1931 var callsite
= v
.get_method
(node
, recvtype
, name
, for_self
)
1933 if callsite
== null then return
1934 self.callsite
= callsite
1936 var args
= compute_raw_arguments
1938 callsite
.check_signature
(v
, node
, args
)
1940 var readtype
= callsite
.msignature
.return_mtype
1941 if readtype
== null then
1942 v
.error
(node
, "Error: `{name}` is not a function.")
1946 var wcallsite
= v
.get_method
(node
, recvtype
, name
+ "=", self.n_expr
isa ASelfExpr)
1947 if wcallsite
== null then return
1948 self.write_callsite
= wcallsite
1950 var wtype
= self.resolve_reassignment
(v
, readtype
, wcallsite
.msignature
.mparameters
.last
.mtype
)
1951 if wtype
== null then return
1953 args
= args
.to_a
# duplicate so raw_arguments keeps only the getter args
1954 args
.add
(self.n_value
)
1955 wcallsite
.check_signature
(v
, node
, args
)
1957 self.is_typed
= true
1961 redef class ACallReassignExpr
1962 redef fun property_name
do return n_qid
.n_id
.text
1963 redef fun property_node
do return n_qid
.n_id
1964 redef fun compute_raw_arguments
do return n_args
.to_a
1967 redef class ABraReassignExpr
1968 redef fun property_name
do return "[]"
1969 redef fun compute_raw_arguments
do return n_args
.to_a
1972 redef class AInitExpr
1973 redef fun property_name
do return "init"
1974 redef fun property_node
do return n_kwinit
1975 redef fun compute_raw_arguments
do return n_args
.to_a
1979 fun to_a
: Array[AExpr] do return self.n_exprs
.to_a
1984 redef class ASuperExpr
1985 # The method to call if the super is in fact a 'super init call'
1986 # Note: if the super is a normal call-next-method, then this attribute is null
1987 var callsite
: nullable CallSite
1989 # The method to call is the super is a standard `call-next-method` super-call
1990 # Note: if the super is a special super-init-call, then this attribute is null
1991 var mpropdef
: nullable MMethodDef
1993 redef fun accept_typing
(v
)
1995 var anchor
= v
.anchor
1996 assert anchor
!= null
1997 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1998 assert recvtype
!= null
1999 var mproperty
= v
.mpropdef
.mproperty
2000 if not mproperty
isa MMethod then
2001 v
.error
(self, "Error: `super` only usable in a `method`.")
2004 var superprops
= mproperty
.lookup_super_definitions
(v
.mmodule
, anchor
)
2005 if superprops
.length
== 0 then
2006 if mproperty
.is_init
and v
.mpropdef
.is_intro
then
2007 process_superinit
(v
)
2010 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
2013 # FIXME: covariance of return type in linear extension?
2014 var superprop
= superprops
.first
2016 var msignature
= superprop
.msignature
.as(not null)
2017 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
2018 var args
= self.n_args
.to_a
2019 if args
.length
> 0 then
2020 signaturemap
= v
.check_signature
(self, args
, mproperty
, msignature
)
2022 self.mtype
= msignature
.return_mtype
2023 self.is_typed
= true
2024 v
.mpropdef
.has_supercall
= true
2025 mpropdef
= v
.mpropdef
.as(MMethodDef)
2028 # The mapping used on the call to associate arguments to parameters.
2029 # If null then no specific association is required.
2030 var signaturemap
: nullable SignatureMap
2032 private fun process_superinit
(v
: TypeVisitor)
2034 var anchor
= v
.anchor
2035 assert anchor
!= null
2036 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
2037 assert recvtype
!= null
2038 var mpropdef
= v
.mpropdef
2039 assert mpropdef
isa MMethodDef
2040 var mproperty
= mpropdef
.mproperty
2041 var superprop
: nullable MMethodDef = null
2042 for msupertype
in mpropdef
.mclassdef
.supertypes
do
2043 msupertype
= msupertype
.anchor_to
(v
.mmodule
, anchor
)
2044 var errcount
= v
.modelbuilder
.toolcontext
.error_count
2045 var candidate
= v
.try_get_mproperty_by_name2
(self, msupertype
, mproperty
.name
).as(nullable MMethod)
2046 if candidate
== null then
2047 if v
.modelbuilder
.toolcontext
.error_count
> errcount
then return # Forward error
2048 continue # Try next super-class
2050 if superprop
!= null and candidate
.is_root_init
then
2053 if superprop
!= null and superprop
.mproperty
!= candidate
and not superprop
.mproperty
.is_root_init
then
2054 v
.error
(self, "Error: conflicting super constructor to call for `{mproperty}`: `{candidate.full_name}`, `{superprop.mproperty.full_name}`")
2057 var candidatedefs
= candidate
.lookup_definitions
(v
.mmodule
, anchor
)
2058 if superprop
!= null and superprop
.mproperty
== candidate
then
2059 if superprop
== candidatedefs
.first
then continue
2060 candidatedefs
.add
(superprop
)
2062 if candidatedefs
.length
> 1 then
2063 v
.error
(self, "Error: conflicting property definitions for property `{mproperty}` in `{recvtype}`: {candidatedefs.join(", ")}")
2066 superprop
= candidatedefs
.first
2068 if superprop
== null then
2069 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
2073 var msignature
= superprop
.new_msignature
or else superprop
.msignature
.as(not null)
2074 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
2076 var callsite
= new CallSite(hot_location
, recvtype
, v
.mmodule
, v
.anchor
, true, superprop
.mproperty
, superprop
, msignature
, false)
2077 self.callsite
= callsite
2079 var args
= self.n_args
.to_a
2080 if args
.length
> 0 then
2081 callsite
.check_signature
(v
, self, args
)
2083 # Check there is at least enough parameters
2084 if mpropdef
.msignature
.arity
< msignature
.arity
then
2085 v
.error
(self, "Error: not enough implicit arguments to pass. Got `{mpropdef.msignature.arity}`, expected at least `{msignature.arity}`. Signature is `{msignature}`.")
2088 # Check that each needed parameter is conform
2090 for sp
in msignature
.mparameters
do
2091 var p
= mpropdef
.msignature
.mparameters
[i
]
2092 if not v
.is_subtype
(p
.mtype
, sp
.mtype
) then
2093 v
.error
(self, "Type Error: expected argument #{i} of type `{sp.mtype}`, got implicit argument `{p.name}` of type `{p.mtype}`. Signature is {msignature}")
2100 self.is_typed
= true
2106 redef class ANewExpr
2107 # The constructor invoked by the new.
2108 var callsite
: nullable CallSite
2110 # The designated type
2111 var recvtype
: nullable MClassType
2113 redef fun accept_typing
(v
)
2115 var recvtype
= v
.resolve_mtype
(self.n_type
)
2116 if recvtype
== null then return
2118 if not recvtype
isa MClassType then
2119 if recvtype
isa MNullableType then
2120 v
.error
(self, "Type Error: cannot instantiate the nullable type `{recvtype}`.")
2122 else if recvtype
isa MFormalType then
2123 v
.error
(self, "Type Error: cannot instantiate the formal type `{recvtype}`.")
2126 v
.error
(self, "Type Error: cannot instantiate the type `{recvtype}`.")
2131 self.recvtype
= recvtype
2132 var kind
= recvtype
.mclass
.kind
2135 var nqid
= self.n_qid
2137 if nqid
!= null then
2138 name
= nqid
.n_id
.text
2144 if name
== "intern" then
2145 if kind
!= concrete_kind
then
2146 v
.error
(self, "Type Error: cannot instantiate {kind} {recvtype}.")
2149 if n_args
.n_exprs
.not_empty
then
2150 v
.error
(n_args
, "Type Error: the intern constructor expects no arguments.")
2154 self.mtype
= recvtype
2158 var callsite
= v
.get_method
(node
, recvtype
, name
, false)
2159 if callsite
== null then return
2161 if not callsite
.mproperty
.is_new
then
2162 if kind
!= concrete_kind
then
2163 v
.error
(self, "Type Error: cannot instantiate {kind} `{recvtype}`.")
2166 self.mtype
= recvtype
2168 self.mtype
= callsite
.msignature
.return_mtype
2169 assert self.mtype
!= null
2172 self.callsite
= callsite
2174 if not callsite
.mproperty
.is_init_for
(recvtype
.mclass
) then
2175 v
.error
(self, "Error: `{name}` is not a constructor.")
2179 var args
= n_args
.to_a
2180 callsite
.check_signature
(v
, node
, args
)
2186 redef class AAttrFormExpr
2187 # The attribute accessed.
2188 var mproperty
: nullable MAttribute
2190 # The static type of the attribute.
2191 var attr_type
: nullable MType
2193 # Resolve the attribute accessed.
2194 private fun resolve_property
(v
: TypeVisitor)
2196 var recvtype
= v
.visit_expr
(self.n_expr
)
2197 if recvtype
== null then return # Skip error
2198 var node
= self.n_id
2199 var name
= node
.text
2200 if recvtype
isa MNullType then
2201 v
.error
(node
, "Error: attribute `{name}` access on `null`.")
2205 var unsafe_type
= v
.anchor_to
(recvtype
)
2206 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
2207 if mproperty
== null then
2208 v
.modelbuilder
.error
(node
, "Error: attribute `{name}` does not exist in `{recvtype}`.")
2211 assert mproperty
isa MAttribute
2212 self.mproperty
= mproperty
2214 var mpropdefs
= mproperty
.lookup_definitions
(v
.mmodule
, unsafe_type
)
2215 assert mpropdefs
.length
== 1
2216 var mpropdef
= mpropdefs
.first
2217 var attr_type
= mpropdef
.static_mtype
2218 if attr_type
== null then return # skip error
2219 attr_type
= v
.resolve_for
(attr_type
, recvtype
, self.n_expr
isa ASelfExpr)
2220 self.attr_type
= attr_type
2224 redef class AAttrExpr
2225 redef fun accept_typing
(v
)
2227 self.resolve_property
(v
)
2228 self.mtype
= self.attr_type
2233 redef class AAttrAssignExpr
2234 redef fun accept_typing
(v
)
2236 self.resolve_property
(v
)
2237 var mtype
= self.attr_type
2239 v
.visit_expr_subtype
(self.n_value
, mtype
)
2240 self.is_typed
= mtype
!= null
2244 redef class AAttrReassignExpr
2245 redef fun accept_typing
(v
)
2247 self.resolve_property
(v
)
2248 var mtype
= self.attr_type
2249 if mtype
== null then return # Skip error
2251 var rettype
= self.resolve_reassignment
(v
, mtype
, mtype
)
2253 self.is_typed
= rettype
!= null
2257 redef class AIssetAttrExpr
2258 redef fun accept_typing
(v
)
2260 self.resolve_property
(v
)
2261 var mtype
= self.attr_type
2262 if mtype
== null then return # Skip error
2264 var recvtype
= self.n_expr
.mtype
.as(not null)
2265 var bound
= v
.resolve_for
(mtype
, recvtype
, false)
2266 if bound
isa MNullableType then
2267 v
.error
(n_id
, "Type Error: `isset` on a nullable attribute.")
2269 self.mtype
= v
.type_bool
(self)
2273 redef class AVarargExpr
2274 redef fun accept_typing
(v
)
2276 # This kind of pseudo-expression can be only processed trough a signature
2277 # See `check_signature`
2278 # Other cases are a syntax error.
2279 v
.error
(self, "Syntax Error: unexpected `...`.")
2285 redef class ADebugTypeExpr
2286 redef fun accept_typing
(v
)
2288 var expr
= v
.visit_expr
(self.n_expr
)
2289 if expr
== null then return
2290 var unsafe
= v
.anchor_to
(expr
)
2291 var ntype
= self.n_type
2292 var mtype
= v
.resolve_mtype
(ntype
)
2293 if mtype
!= null and mtype
!= expr
then
2294 var umtype
= v
.anchor_to
(mtype
)
2295 v
.modelbuilder
.warning
(self, "debug", "Found type {expr} (-> {unsafe}), expected {mtype} (-> {umtype})")
2297 self.is_typed
= true