Completed
Pull Request — master (#45)
by Matthias
03:25
created

UsedSymbolCollector   B

Complexity

Total Complexity 44

Size/Duplication

Total Lines 173
Duplicated Lines 0 %

Test Coverage

Coverage 98.82%

Importance

Changes 0
Metric Value
wmc 44
dl 0
loc 173
ccs 84
cts 85
cp 0.9882
rs 8.3396
c 0
b 0
f 0

15 Methods

Rating   Name   Duplication   Size   Complexity  
B recordFunctionParameterTypesUsage() 0 11 6
A getCollectedSymbols() 0 3 1
A recordCatchUsage() 0 5 3
A recordConstantFetchUsage() 0 4 2
A __construct() 0 2 1
A recordImplementsUsage() 0 4 2
A beforeTraverse() 0 5 1
A recordFunctionCallUsage() 0 7 4
A recordExtendsUsage() 0 8 3
B recordClassExpressionUsage() 0 12 8
A enterNode() 0 13 1
B recordFunctionReturnTypeUsage() 0 10 5
A recordUsageOfByString() 0 3 1
A recordUsageOf() 0 3 1
B recordTraitUsage() 0 15 5

How to fix   Complexity   

Complex Class

Complex classes like UsedSymbolCollector often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.

Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.

While breaking up the class, it is a good idea to analyze how other classes use UsedSymbolCollector, and based on these observations, apply Extract Interface, too.

1
<?php
2
3
namespace ComposerRequireChecker\NodeVisitor;
4
5
use PhpParser\Node;
6
use PhpParser\NodeVisitorAbstract;
7
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final class UsedSymbolCollector extends NodeVisitorAbstract
9
{
10
    /**
11
     * @var mixed[]
12
     */
13
    private $collectedSymbols = [];
14
15 23
    public function __construct()
16
    {
17 23
    }
18
19
    /**
20
     * @return string[]
21
     */
22 23
    public function getCollectedSymbols(): array
23
    {
24 23
        return array_keys($this->collectedSymbols);
25
    }
26
27
    /**
28
     * {@inheritDoc}
29
     */
30 2
    public function beforeTraverse(array $nodes)
31
    {
32 2
        $this->collectedSymbols = [];
33
34 2
        return parent::beforeTraverse($nodes);
0 ignored issues
show
Bug introduced by
Are you sure the usage of parent::beforeTraverse($nodes) targeting PhpParser\NodeVisitorAbstract::beforeTraverse() seems to always return null.

This check looks for function or method calls that always return null and whose return value is used.

class A
{
    function getObject()
    {
        return null;
    }

}

$a = new A();
if ($a->getObject()) {

The method getObject() can return nothing but null, so it makes no sense to use the return value.

The reason is most likely that a function or method is imcomplete or has been reduced for debug purposes.

Loading history...
35
    }
36
37
    /**
38
     * {@inheritDoc}
39
     */
40 23
    public function enterNode(Node $node)
41
    {
42 23
        $this->recordExtendsUsage($node);
43 23
        $this->recordImplementsUsage($node);
44 23
        $this->recordClassExpressionUsage($node);
45 23
        $this->recordCatchUsage($node);
46 23
        $this->recordFunctionCallUsage($node);
47 23
        $this->recordFunctionParameterTypesUsage($node);
48 23
        $this->recordFunctionReturnTypeUsage($node);
49 23
        $this->recordConstantFetchUsage($node);
50 23
        $this->recordTraitUsage($node);
51
52 23
        return parent::enterNode($node);
0 ignored issues
show
Bug introduced by
Are you sure the usage of parent::enterNode($node) targeting PhpParser\NodeVisitorAbstract::enterNode() seems to always return null.

This check looks for function or method calls that always return null and whose return value is used.

class A
{
    function getObject()
    {
        return null;
    }

}

$a = new A();
if ($a->getObject()) {

The method getObject() can return nothing but null, so it makes no sense to use the return value.

The reason is most likely that a function or method is imcomplete or has been reduced for debug purposes.

Loading history...
53
    }
54
55 23
    private function recordExtendsUsage(Node $node)
56
    {
57 23
        if ($node instanceof Node\Stmt\Class_) {
58 4
            array_map([$this, 'recordUsageOf'], array_filter([$node->extends]));
59
        }
60
61 23
        if ($node instanceof Node\Stmt\Interface_) {
62 2
            array_map([$this, 'recordUsageOf'], array_filter($node->extends));
63
        }
64 23
    }
65
66 23
    private function recordImplementsUsage(Node $node)
67
    {
68 23
        if ($node instanceof Node\Stmt\Class_) {
69 4
            array_map([$this, 'recordUsageOf'], $node->implements);
70
        }
71 23
    }
72
73 23
    private function recordClassExpressionUsage(Node $node)
74
    {
75 23
        if (($node instanceof Node\Expr\StaticCall
76 22
                || $node instanceof Node\Expr\StaticPropertyFetch
77 21
                || $node instanceof Node\Expr\ClassConstFetch
78 20
                || $node instanceof Node\Expr\New_
79 23
                || $node instanceof Node\Expr\Instanceof_
80
            )
81 23
            && ($nodeClass = $node->class)
0 ignored issues
show
Documentation Bug introduced by
It seems like $node->class can also be of type PhpParser\Node\Stmt\Class_. However, the property $class is declared as type PhpParser\Node\Name|PhpParser\Node\Expr. Maybe add an additional type check?

Our type inference engine has found a suspicous assignment of a value to a property. This check raises an issue when a value that can be of a mixed type is assigned to a property that is type hinted more strictly.

For example, imagine you have a variable $accountId that can either hold an Id object or false (if there is no account id yet). Your code now assigns that value to the id property of an instance of the Account class. This class holds a proper account, so the id value must no longer be false.

Either this assignment is in error or a type check should be added for that assignment.

class Id
{
    public $id;

    public function __construct($id)
    {
        $this->id = $id;
    }

}

class Account
{
    /** @var  Id $id */
    public $id;
}

$account_id = false;

if (starsAreRight()) {
    $account_id = new Id(42);
}

$account = new Account();
if ($account instanceof Id)
{
    $account->id = $account_id;
}
Loading history...
82 23
            && $nodeClass instanceof Node\Name
83
        ) {
84 6
            $this->recordUsageOf($nodeClass);
85
        }
86 23
    }
87
88 23
    private function recordCatchUsage(Node $node)
89
    {
90 23
        if ($node instanceof Node\Stmt\Catch_) {
91 2
            foreach ($node->types as $type) {
92 2
                $this->recordUsageOf($type);
93
            }
94
        }
95 23
    }
96
97 23
    private function recordFunctionCallUsage(Node $node)
98
    {
99 23
        if ($node instanceof Node\Expr\FuncCall
100 23
            && ($nodeName = $node->name)
101 23
            && $nodeName instanceof Node\Name
102
        ) {
103 2
            $this->recordUsageOf($nodeName);
104
        }
105 23
    }
106
107 23
    private function recordFunctionParameterTypesUsage(Node $node)
108
    {
109 23
        if ($node instanceof Node\Stmt\Function_
110 23
            || $node instanceof Node\Stmt\ClassMethod
111
        ) {
112 9
            foreach ($node->getParams() as $param) {
113 5
                if ($param->type instanceof Node\Name) {
114 3
                    $this->recordUsageOf($param->type);
115
                }
116 5
                if (is_string($param->type)) {
117 5
                    $this->recordUsageOfByString($param->type);
118
                }
119
            }
120
        }
121 23
    }
122
123 23
    private function recordFunctionReturnTypeUsage(Node $node)
124
    {
125 23
        if ($node instanceof Node\Stmt\Function_
126 23
            || $node instanceof Node\Stmt\ClassMethod
127
        ) {
128 9
            if ($node->getReturnType() instanceof Node\Name) {
129 3
                $this->recordUsageOf($node->getReturnType());
130
            }
131 9
            if (is_string($node->getReturnType())) {
132 3
                $this->recordUsageOfByString($node->getReturnType());
133
            }
134
        }
135 23
    }
136
137 23
    private function recordConstantFetchUsage(Node $node)
138
    {
139 23
        if ($node instanceof Node\Expr\ConstFetch) {
140 2
            $this->recordUsageOf($node->name);
141
        }
142 23
    }
143
144 23
    private function recordTraitUsage(Node $node)
145
    {
146 23
        if (!$node instanceof Node\Stmt\TraitUse) {
147 21
            return;
148
        }
149
150 2
        array_map([$this, 'recordUsageOf'], $node->traits);
151
152 2
        foreach ($node->adaptations as $adaptation) {
153 1
            if (null !== $adaptation->trait) {
154
                $this->recordUsageOf($adaptation->trait);
155
            }
156
157 1
            if ($adaptation instanceof Node\Stmt\TraitUseAdaptation\Precedence) {
158 1
                array_map([$this, 'recordUsageOf'], $adaptation->insteadof);
159
            }
160
        }
161 2
    }
162
163
    /**
164
     * @param Node\Name $symbol
165
     *
166
     * @return void
167
     */
168 19
    private function recordUsageOf(Node\Name $symbol)
169
    {
170 19
        $this->collectedSymbols[(string)$symbol] = $symbol;
171 19
    }
172
173
    /**
174
     * @param Node\Name $symbol
175
     *
176
     * @return void
177
     */
178 5
    private function recordUsageOfByString(string $symbol)
179
    {
180 5
        $this->collectedSymbols[$symbol] = $symbol;
181 5
    }
182
}
183