D-Scanner/src/dscanner/analysis/constructors.d

113 lines
2.8 KiB
D

module dscanner.analysis.constructors;
import dparse.ast;
import dparse.lexer;
import std.stdio;
import dscanner.analysis.base;
import dscanner.analysis.helpers;
import dsymbol.scope_ : Scope;
final class ConstructorCheck : BaseAnalyzer
{
alias visit = BaseAnalyzer.visit;
this(string fileName, const(Scope)* sc, bool skipTests = false)
{
super(fileName, sc, skipTests);
}
override void visit(const ClassDeclaration classDeclaration)
{
immutable bool oldHasDefault = hasDefaultArgConstructor;
immutable bool oldHasNoArg = hasNoArgConstructor;
hasNoArgConstructor = false;
hasDefaultArgConstructor = false;
immutable State prev = state;
state = State.inClass;
classDeclaration.accept(this);
if (hasNoArgConstructor && hasDefaultArgConstructor)
{
addErrorMessage(classDeclaration.name.line,
classDeclaration.name.column, "dscanner.confusing.constructor_args",
"This class has a zero-argument constructor as well as a"
~ " constructor with one default argument. This can be confusing.");
}
hasDefaultArgConstructor = oldHasDefault;
hasNoArgConstructor = oldHasNoArg;
state = prev;
}
override void visit(const StructDeclaration structDeclaration)
{
immutable State prev = state;
state = State.inStruct;
structDeclaration.accept(this);
state = prev;
}
override void visit(const Constructor constructor)
{
final switch (state)
{
case State.inStruct:
if (constructor.parameters.parameters.length == 1
&& constructor.parameters.parameters[0].default_ !is null)
{
addErrorMessage(constructor.line, constructor.column,
"dscanner.confusing.struct_constructor_default_args",
"This struct constructor can never be called with its "
~ "default argument.");
}
break;
case State.inClass:
if (constructor.parameters.parameters.length == 1
&& constructor.parameters.parameters[0].default_ !is null)
{
hasDefaultArgConstructor = true;
}
else if (constructor.parameters.parameters.length == 0)
hasNoArgConstructor = true;
break;
case State.ignoring:
break;
}
}
private:
enum State : ubyte
{
ignoring,
inClass,
inStruct
}
State state;
bool hasNoArgConstructor;
bool hasDefaultArgConstructor;
}
unittest
{
import dscanner.analysis.config : StaticAnalysisConfig, Check, disabledConfig;
StaticAnalysisConfig sac = disabledConfig();
sac.constructor_check = Check.enabled;
assertAnalyzerWarnings(q{
class Cat // [warn]: This class has a zero-argument constructor as well as a constructor with one default argument. This can be confusing.
{
this() {}
this(string name = "kittie") {}
}
struct Dog
{
this() {}
this(string name = "doggie") {} // [warn]: This struct constructor can never be called with its default argument.
}
}c, sac);
stderr.writeln("Unittest for ConstructorCheck passed.");
}