# FIXME Split the module in three parts: extension of the modele, building phase and the "re-driving"
module contracts
-import astbuilder
import parse_annotations
import phase
import semantize
+intrude import model_contract
+intrude import astbuilder
intrude import modelize_property
intrude import scope
intrude import typing
# The implementation of the contracts is done in two visits.
#
# - First step, the visitor analyzes and constructs the contracts
- # for each class (invariant) and method (expects, ensures).
+ # for each class (invariant) and method (expect, ensure).
#
# - Second step the visitor analyzes each `ASendExpr` to see
# if the callsite calls a method with a contract. If this is
end
end
-# This visitor checks the `AMethPropdef` and the `AClassDef` to check if they have a contract annotation or it's a redefinition with a inheritance contract
+# Visitor to build all contracts.
private class ContractsVisitor
super Visitor
+ # Instance of the toolcontext
var toolcontext: ToolContext
# The main module
var current_location: Location is noinit
# Is the contrat is an introduction or not?
+ # This attribute has the same value as the `is_intro` of the propdef attached to the contract.
+ # Note : For MClassDef `is_intro_contract == false`. This is due to the fact that a method for checking invariants is systematically added to the root object class.
var is_intro_contract: Bool is noinit
# Actual visited class
# is `no_contract` annotation was found
var find_no_contract = false
+ # The reference to the `in_contract` attribute.
+ # This attribute is used to disable contract verification when you are already in a contract verification.
+ # Keep the `in_contract` attribute to avoid searching at each contrat
+ var in_contract_attribute: nullable MAttribute = null
+
redef fun visit(node)
do
node.create_contracts(self)
end
# Verification if the construction of the contract is necessary.
- # Three cases are checked for `expects`:
+ # Three cases are checked for `expect`:
#
- # - Is the `--full-contract` option it's use?
- # - Is the method is in the main package
- # - Is the method is in a direct imported package.
+ # - Was the `--full-contract` option passed?
+ # - Is the method is in the main package?
+ # - Is the method is in a direct imported package?
#
- fun check_usage_expects(actual_mmodule: MModule): Bool
+ fun check_usage_expect(actual_mmodule: MModule): Bool
do
var main_package = mainmodule.mpackage
var actual_package = actual_mmodule.mpackage
end
# Verification if the construction of the contract is necessary.
- # Two cases are checked for `ensures`:
+ # Two cases are checked for `ensure`:
#
- # - Is the `--full-contract` option it's use?
- # - Is the method is in the main package
+ # - Was the `--full-contract` option passed?
+ # - Is the method is in the main package?
#
- fun check_usage_ensures(actual_mmodule: MModule): Bool
+ fun check_usage_ensure(actual_mmodule: MModule): Bool
do
return toolcontext.opt_full_contract.value or mainmodule.mpackage == actual_mmodule.mpackage
end
+ # Inject the incontract attribute (`_in_contract_`) in the `Sys` class
+ # This attribute allows to check if the contract need to be executed
+ private fun inject_incontract_in_sys
+ do
+ # If the `in_contract_attribute` already know just return
+ if in_contract_attribute != null then return
+
+ var sys_class = toolcontext.modelbuilder.get_mclass_by_name(visited_module, mainmodule, "Sys")
+
+ # Try to get the `in_contract` property, if it has already defined in a previously visited module.
+ var in_contract_property = toolcontext.modelbuilder.try_get_mproperty_by_name(visited_module, sys_class.intro, "__in_contract_")
+ if in_contract_property != null then
+ self.in_contract_attribute = in_contract_property.as(MAttribute)
+ return
+ end
+
+ var bool_false = new AFalseExpr.make(mainmodule.bool_type)
+ var n_in_contract_attribute = toolcontext.modelbuilder.create_attribute_from_name("__in_contract_", sys_class.intro, mainmodule.bool_type, public_visibility).create_setter(toolcontext.modelbuilder, true).define_default(bool_false)
+
+ in_contract_attribute = n_in_contract_attribute.mpropdef.mproperty
+ end
+
+ # Return the `_in_contract_` attribute.
+ # If the attribute `_in_contract_` does not exist it's injected with `inject_incontract_in_sys`
+ private fun get_incontract: MAttribute
+ do
+ if self.in_contract_attribute == null then inject_incontract_in_sys
+ return in_contract_attribute.as(not null)
+ end
+
+ # Return an `AIfExpr` with the contract encapsulated by an `if` to check if it's already in a contract verification.
+ #
+ # Example:
+ # ~~~nitish
+ # class A
+ # fun bar([...]) is except([...])
+ #
+ # fun _contract_bar([...])
+ # do
+ # if not sys._in_contract_ then
+ # sys._in_contract_ = true
+ # _bar_expect([...])
+ # sys._in_contract_ = false
+ # end
+ # bar([...])
+ # end
+ #
+ # fun _bar_expect([...])
+ # end
+ # ~~~~
+ #
+ private fun encapsulated_contract_call(visited_method: AMethPropdef, call_to_contracts: Array[ACallExpr]): AIfExpr
+ do
+ var sys_property = toolcontext.modelbuilder.model.get_mproperties_by_name("sys").first.as(MMethod)
+ var callsite_sys = ast_builder.create_callsite(toolcontext.modelbuilder, visited_method, sys_property, true)
+
+ var incontract_attribute = get_incontract
+
+ var callsite_get_incontract = ast_builder.create_callsite(toolcontext.modelbuilder, visited_method, incontract_attribute.getter.as(MMethod), false)
+ var callsite_set_incontract = ast_builder.create_callsite(toolcontext.modelbuilder, visited_method, incontract_attribute.setter.as(MMethod), false)
+
+ var n_condition = ast_builder.make_not(ast_builder.make_call(ast_builder.make_call(new ASelfExpr, callsite_sys, null), callsite_get_incontract, null))
+
+ var n_if = ast_builder.make_if(n_condition, null)
+
+ var if_then_block = n_if.n_then.as(ABlockExpr)
+
+ if_then_block.add(ast_builder.make_call(ast_builder.make_call(new ASelfExpr, callsite_sys, null), callsite_set_incontract, [new ATrueExpr.make(mainmodule.bool_type)]))
+ if_then_block.add_all(call_to_contracts)
+ if_then_block.add(ast_builder.make_call(ast_builder.make_call(new ASelfExpr, callsite_sys, null), callsite_set_incontract, [new AFalseExpr.make(mainmodule.bool_type)]))
+
+ return n_if
+ end
end
# This visitor checks the `callsite` to see if the target `mpropdef` has a contract.
private class CallSiteVisitor
super Visitor
+
+ # Instance of the toolcontext
var toolcontext: ToolContext
# Actual visited method
# If it's the case the callsite is replaced by another callsite to the contract method.
private fun drive_method_contract(callsite: CallSite): CallSite
do
- if callsite.mpropdef.has_contract then
+ if callsite.mproperty.mcontract_facet != null then
var contract_facet = callsite.mproperty.mcontract_facet
var visited_mpropdef = visited_method.mpropdef
assert contract_facet != null and visited_mpropdef != null
- var unsafe_mtype = callsite.recv.resolve_for(visited_mpropdef.mclassdef.bound_mtype, callsite.anchor, visited_mpropdef.mclassdef.mmodule, true)
-
- # This check is needed because the contract can appear after the introduction.
- if unsafe_mtype.has_mproperty(visited_method.mpropdef.mclassdef.mmodule, contract_facet) then
- var type_visitor = new TypeVisitor(toolcontext.modelbuilder, visited_mpropdef)
- var drived_callsite = type_visitor.build_callsite_by_property(visited_method, callsite.recv, contract_facet, callsite.recv_is_self)
- # This never happen this check is here for debug
- assert drived_callsite != null
- return drived_callsite
- end
+ var type_visitor = new TypeVisitor(toolcontext.modelbuilder, visited_mpropdef)
+ var drived_callsite = type_visitor.build_callsite_by_property(visited_method, callsite.recv, contract_facet, callsite.recv_is_self)
+ # This never happen this check is here for debug
+ assert drived_callsite != null
+ return drived_callsite
end
return callsite
end
redef class AAnnotation
- # Returns the conditions of annotation parameters in the form of and expr
- # exemple:
- # the contract ensures(true, i == 10, f >= 1.0)
- # return this condition (true and i == 10 and f >= 1.0)
+ # Returns the conditions of annotation parameters. If there are several parameters, the result is an `AAndExpr`
+ # Example:
+ # the contract `ensure(true, i == 10, f >= 1.0)`
+ # return this condition `(true and i == 10 and f >= 1.0)`
private fun construct_condition(v : ContractsVisitor): AExpr
do
var n_condition = n_args.first
end
end
-# The root of all contracts
-#
-# The objective of this class is to provide the set
-# of services must be implemented or provided by a contract
-abstract class MContract
- super MMethod
+redef class MContract
# Define the name of the contract
fun contract_name: String is abstract
private fun adapt_block_to_contract(v: ContractsVisitor, n_mpropdef: AMethPropdef) is abstract
# Adapt the msignature specifically for the contract method
- private fun adapt_specific_msignature(m_signature: MSignature): MSignature do return m_signature.adapt_to_condition
+ private fun adapt_specific_msignature(m_signature: MSignature): MSignature do return m_signature.adapt_to_contract
# Adapt the nsignature specifically for the contract method
- private fun adapt_specific_nsignature(n_signature: ASignature): ASignature do return n_signature.adapt_to_condition(null)
+ private fun adapt_specific_nsignature(n_signature: ASignature): ASignature do return n_signature.adapt_to_contract
# Adapt the `m_signature` to the contract
# If it is not null call the specific adapt `m_signature` for the contract
# Create the initial contract (intro)
# All contracts have the same implementation for the introduction.
#
+ # Example:
+ # ~~~nitish
# fun contrat([...])
# do
# assert contract_condition
# end
+ # ~~~
#
private fun create_intro_contract(v: ContractsVisitor, n_condition: nullable AExpr, mclassdef: MClassDef): AMethPropdef
do
end
end
-# A expect (precondition) contract representation
-# This method check if the requirements of the called method is true.
-class MExpect
- super MContract
+redef class MExpect
# Define the name of the contract
- redef fun contract_name: String do return "expects"
+ redef fun contract_name: String do return "expect"
# Display warning if no contract is defined at introduction `expect`,
# because if no contract is defined at the introduction the added
# contracts will not cause any error even if they are not satisfied.
#
- # exemple
+ # Example:
# ~~~nitish
# class A
# fun bar [...]
- # fun _bar_expects([...])
+ # fun _bar_expect([...])
# do
# [empty contract]
# end
# end
#
# redef class A
- # redef fun bar is expects(contract_condition)
- # redef fun _bar_expects([...])
+ # redef fun bar is expect(contract_condition)
+ # redef fun _bar_expect([...])
# do
- # if not (contract_condition) then super
+ # if (contract_condition) then return
+ # super
# end
# end
# ~~~~
end
end
-# The root of all contracts where the call is after the execution of the original method (`invariants` and `ensures`).
-abstract class BottomMContract
- super MContract
+redef class BottomMContract
redef fun create_nblock(v: ContractsVisitor, n_condition: AExpr, args: Array[AExpr]): ABlockExpr
do
return n_block
end
- # Inject the result variable in the `n_block` of the given `n_mpropdef`.
+ # Inject the `result` variable into the `n_block` of the given n_mpropdef`.
+ #
+ # The purpose of the variable is to capture return values to use it in contracts.
private fun inject_result(v: ContractsVisitor, n_mpropdef: AMethPropdef, ret_type: MType): Variable
do
var actual_block = n_mpropdef.n_block
end
end
-# A ensure (postcondition) representation
-# This method check if the called method respects the expectations of the caller.
-class MEnsure
- super BottomMContract
+redef class MEnsure
# Define the name of the contract
- redef fun contract_name: String do return "ensures"
+ redef fun contract_name: String do return "ensure"
redef fun adapt_specific_msignature(m_signature: MSignature): MSignature
do
end
end
-redef class MMethod
-
- # The contract facet of the method
- # it's representing the method with contract
- # This method call the contract and the method
- var mcontract_facet: nullable MMethod = null
-
- # The expected contract method
- var mexpect: nullable MExpect = null
-
- # The ensure contract method
- var mensure: nullable MEnsure = null
-
- # Check if the MMethod has no ensure contract
- # if this is the case returns false and built it
- # else return true
- private fun check_exist_ensure: Bool
- do
- if self.mensure != null then return true
- # build a new `MEnsure` contract
- self.mensure = new MEnsure(intro_mclassdef, "_ensures_{name}", intro_mclassdef.location, public_visibility)
- return false
- end
-
- # Check if the MMethod has no expect contract
- # if this is the case returns false and built it
- # else return true
- private fun check_exist_expect: Bool
- do
- if self.mexpect != null then return true
- # build a new `MExpect` contract
- self.mexpect = new MExpect(intro_mclassdef, "_expects_{name}", intro_mclassdef.location, public_visibility)
- return false
- end
-
- # Check if the MMethod has an contract facet
- # If the method has no contract facet she create it
- private fun check_exist_contract_facet(mpropdef : MMethodDef): Bool
- do
- if self.mcontract_facet != null then return true
- # build a new `MMethod` contract
- self.mcontract_facet = new MMethod(mpropdef.mclassdef, "_contract_{name}", mpropdef.mclassdef.location, public_visibility)
- return false
- end
-end
-
redef class MMethodDef
# Verification of the contract facet
# Check if a contract facet already exists to use it again or if it is necessary to create it.
- private fun check_contract_facet(v: ContractsVisitor, n_signature: ASignature, mcontract: MContract, exist_contract: Bool)
+ private fun check_contract_facet(v: ContractsVisitor, n_signature: ASignature, classdef: MClassDef, mcontract: MContract, exist_contract: Bool)
do
- var exist_contract_facet = mproperty.check_exist_contract_facet(self)
+ var exist_contract_facet = mproperty.has_contract_facet
if exist_contract_facet and exist_contract then return
var contract_facet: AMethPropdef
if not exist_contract_facet then
+ # If has no contract facet in intro just create it
+ if classdef != mproperty.intro_mclassdef then create_contract_facet(v, mproperty.intro_mclassdef, n_signature)
# If has no contract facet just create it
- contract_facet = create_contract_facet(v, n_signature)
+ contract_facet = create_contract_facet(v, classdef, n_signature)
else
- # Check if the contract facet already exist in this context (in this mclassdef)
- if mclassdef.mpropdefs_by_property.has_key(mproperty.mcontract_facet) then
+ # Check if the contract facet already exist in this context (in this classdef)
+ if classdef.mpropdefs_by_property.has_key(mproperty.mcontract_facet) then
# get the define
- contract_facet = v.toolcontext.modelbuilder.mpropdef2node(mclassdef.mpropdefs_by_property[mproperty.mcontract_facet]).as(AMethPropdef)
+ contract_facet = v.toolcontext.modelbuilder.mpropdef2node(classdef.mpropdefs_by_property[mproperty.mcontract_facet]).as(AMethPropdef)
else
# create a new contract facet definition
- contract_facet = create_contract_facet(v, n_signature)
+ contract_facet = create_contract_facet(v, classdef, n_signature)
var block = v.ast_builder.make_block
# super call to the contract facet
var n_super_call = v.ast_builder.make_super_call(n_signature.make_parameter_read(v.ast_builder), null)
end
# Method to create a contract facet of the method
- private fun create_contract_facet(v: ContractsVisitor, n_signature: ASignature): AMethPropdef
+ private fun create_contract_facet(v: ContractsVisitor, classdef: MClassDef, n_signature: ASignature): AMethPropdef
do
- var contract_facet = mproperty.mcontract_facet
- assert contract_facet != null
+ var contract_facet = mproperty.build_contract_facet
# Defines the contract phase is an init or not
# it is necessary to use the contracts on constructor
contract_facet.is_init = self.mproperty.is_init
var m_signature: nullable MSignature = null
if mproperty.intro.msignature != null then m_signature = mproperty.intro.msignature.clone
- var n_contractdef = mclassdef.mclass.create_empty_method(v, contract_facet, mclassdef, m_signature, n_signature)
+ var n_contractdef = classdef.mclass.create_empty_method(v, contract_facet, classdef, m_signature, n_signature)
# FIXME set the location because the callsite creation need the node location
n_contractdef.location = v.current_location
n_contractdef.validate
v.define_signature(mcontract, n_signature, mproperty.intro.msignature)
var conditiondef = v.build_contract(n_annotation, mcontract, mclassdef)
- check_contract_facet(v, n_signature.clone, mcontract, exist_contract)
+ check_contract_facet(v, n_signature.clone, mclassdef, mcontract, exist_contract)
has_contract = true
end
# Is the contract already defined in the context
#
# Exemple :
- # fun foo is expects([...]), expects([...])
+ # fun foo is expect([...]), expect([...])
#
- # Here `check_same_contract` display an error when the second expects is processed
+ # Here `check_same_contract` display an error when the second expect is processed
private fun check_same_contract(v: ContractsVisitor, n_annotation: AAnnotation ,mcontract: MContract): Bool
do
if self.mclassdef.mpropdefs_by_property.has_key(mcontract) then
redef class AMethPropdef
- # Execute all method verification scope flow and typing.
- # It also execute an ast validation to define all parents and all locations
- private fun do_all(toolcontext: ToolContext)
- do
- self.validate
- # FIXME: The `do_` usage it is maybe to much (verification...). Solution: Cut the `do_` methods into simpler parts
- self.do_scope(toolcontext)
- self.do_flow(toolcontext)
- self.do_typing(toolcontext.modelbuilder)
- end
-
# Entry point to create a contract (verification of inheritance, or new contract).
redef fun create_contracts(v)
do
# If this is the case, we built the appropriate contract.
private fun check_annotation(v: ContractsVisitor, n_annotation: AAnnotation)
do
- if n_annotation.name == "expects" then
- if not v.check_usage_expects(mpropdef.mclassdef.mmodule) then return
- var exist_contract = mpropdef.mproperty.check_exist_expect
- mpropdef.construct_contract(v, self.n_signature.as(not null), n_annotation, mpropdef.mproperty.mexpect.as(not null), exist_contract)
- else if n_annotation.name == "ensures" then
- if not v.check_usage_ensures(mpropdef.mclassdef.mmodule) then return
- var exist_contract = mpropdef.mproperty.check_exist_ensure
- mpropdef.construct_contract(v, self.n_signature.as(not null), n_annotation, mpropdef.mproperty.mensure.as(not null), exist_contract)
+ if n_annotation.name == "expect" then
+ if not v.check_usage_expect(mpropdef.mclassdef.mmodule) then return
+ var exist_contract = mpropdef.mproperty.has_expect
+ mpropdef.construct_contract(v, self.n_signature.as(not null), n_annotation, mpropdef.mproperty.build_expect, exist_contract)
+ else if n_annotation.name == "ensure" then
+ if not v.check_usage_ensure(mpropdef.mclassdef.mmodule) then return
+ var exist_contract = mpropdef.mproperty.has_ensure
+ mpropdef.construct_contract(v, self.n_signature.as(not null), n_annotation, mpropdef.mproperty.build_ensure, exist_contract)
else if n_annotation.name == "no_contract" then
# no_contract found set the flag to true
v.find_no_contract = true
redef class MSignature
- # Adapt signature for a expect condition
- # Removed the return type is it not necessary
- private fun adapt_to_condition: MSignature do return new MSignature(mparameters.to_a, null)
+ # Adapt signature for an contract
+ #
+ # The returned `MSignature` is the copy of `self` without return type.
+ private fun adapt_to_contract: MSignature do return new MSignature(mparameters.to_a, null)
- # Adapt signature for a ensure condition
+ # Adapt signature for a ensure contract
#
- # Create new parameter with the return type
+ # The returned `MSignature` is the copy of `self` without return type.
+ # The return type is replaced by a new parameter `result`
private fun adapt_to_ensurecondition: MSignature
do
var rtype = return_mtype
- var msignature = adapt_to_condition
+ var msignature = adapt_to_contract
if rtype != null then
msignature.mparameters.add(new MParameter("result", rtype, false))
end
return msignature
end
- # Adapt signature for a expect condition
- # Removed the return type is it not necessary
+ # The returned `MSignature` is the exact copy of `self`.
private fun clone: MSignature do return new MSignature(mparameters.to_a, return_mtype)
end
return args
end
- # Return a copy of self adapted for the expect condition
- # npropdef it is use to define the parent of the parameters
- private fun adapt_to_condition(return_type: nullable AType): ASignature
+ # Create a new ASignature adapted for contract
+ #
+ # The returned `ASignature` is the copy of `self` without return type.
+ private fun adapt_to_contract: ASignature
do
var adapt_nsignature = self.clone
- adapt_nsignature.n_type = return_type
+ if adapt_nsignature.n_type != null then adapt_nsignature.n_type.detach
return adapt_nsignature
end
- # Return a copy of self adapted for postcondition on npropdef
+ # Create a new ASignature adapted for ensure
+ #
+ # The returned `ASignature` is the copy of `self` without return type.
+ # The return type is replaced by a new parameter `result`
private fun adapt_to_ensurecondition: ASignature do
- var nsignature = adapt_to_condition(null)
+ var nsignature = adapt_to_contract
if ret_type != null then
- var n_id = new TId
- n_id.text = "result"
- var new_param = new AParam
- new_param.n_id = n_id
- new_param.variable = new Variable(n_id.text)
- new_param.variable.declared_type = ret_type
- nsignature.n_params.add new_param
+ var variable = new Variable("result")
+ variable.declared_type = ret_type
+ nsignature.n_params.add new AParam.make(variable, ret_type.create_ast_representation)
end
return nsignature
end
nitlanguage / nit.git / blobdiff