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[java] UseDiamondOperator - add property java7compatibility

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This property is disabled by default, so that the rule
suggests changes that work on java8+ only by default.

Enable the version dependent tests.
This commit is contained in:
Andreas Dangel
2020-05-30 10:38:09 +02:00
parent c2cea9d15b
commit cae1316472
2 changed files with 17 additions and 7 deletions
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11
pmd-java/src/main/resources/category/java/codestyle.xml
View File

@ -1992,6 +1992,11 @@ Use the diamond operator to let the type be inferred automatically. With the Dia
to avoid duplication of the type parameters.
Instead, the compiler is now able to infer the parameter types for constructor calls,
which makes the code also more readable.
The diamond operator has been introduced with java 7. However, type inference has been improved further
with java8, rendering more type parameters unnecessary. This is only possible with java8 and the resulting
code won't compile with java7. If you use java7, make sure to enable `java7compatibility` for this rule to avoid
false positives.
</description>
<priority>3</priority>
<properties>
@ -2004,15 +2009,17 @@ which makes the code also more readable.
|
//StatementExpression[AssignmentOperator and PrimaryExpression/PrimaryPrefix[not(Expression)]]
)
/Expression/PrimaryExpression[not(PrimarySuffix) and not(ancestor::ArgumentList)]
/(Expression | Expression[$java7compatibility = false()]/ConditionalExpression | Expression[$java7compatibility = false()]/ConditionalExpression/Expression)
/PrimaryExpression[not(PrimarySuffix) and not(ancestor::ArgumentList)]
/PrimaryPrefix
/AllocationExpression
[@AnonymousClass=false()]
[ClassOrInterfaceType/TypeArguments[@Diamond=false() and not(.//TypeArgument[@Wildcard=true()])]]
[ClassOrInterfaceType/TypeArguments[@Diamond=false() and not($java7compatibility = true() and .//TypeArgument[@Wildcard=true()])]]
[not(ArrayDimsAndInits)]
]]>
</value>
</property>
<property name="java7compatibility" type="Boolean" description="If disabled, the rule shows also violations that are applicable for java8+" value="false" />
</properties>
<example>
<![CDATA[

13
pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/codestyle/xml/UseDiamondOperator.xml
View File

@ -145,6 +145,7 @@ class Foo {
<test-code>
<description>(J7) Version sensitive tests - avoid possible false positives on Java7</description>
<rule-property name="java7compatibility">true</rule-property>
<expected-problems>0</expected-problems>
<code><![CDATA[
import java.lang.ref.WeakReference;
@ -167,7 +168,7 @@ public class Foo {
]]></code>
</test-code>
<test-code regressionTest="false">
<test-code>
<description>(J8) Version sensitive tests - known false negatives on Java8+</description>
<expected-problems>2</expected-problems>
<expected-linenumbers>6,8</expected-linenumbers>
@ -187,8 +188,9 @@ public class Foo {
<test-code>
<description>False negative for nested type parameters (#2545)</description>
<expected-problems>2</expected-problems>
<expected-linenumbers>7,16</expected-linenumbers>
<rule-property name="java7compatibility">true</rule-property>
<expected-problems>3</expected-problems>
<expected-linenumbers>7,8,17</expected-linenumbers>
<code><![CDATA[
import java.util.List;
import java.util.ArrayList;
@ -197,7 +199,8 @@ import java.lang.ref.WeakReference;
public class UseDiamondOperatorFalseNegative {
List<Map<String,Object>> l = new ArrayList<Map<String,Object>>(); // FN
WeakReference<Class<?>> typeReference = new WeakReference<Class<?>>(String.class); // FP
WeakReference<Class<String>> typeReference = new WeakReference<Class<String>>(String.class); // FN
WeakReference<Class<?>> typeReference2 = new WeakReference<Class<?>>(String.class); // FP
public void test() {
final List<String> l2;
@ -211,7 +214,7 @@ public class UseDiamondOperatorFalseNegative {
]]></code>
</test-code>
<test-code regressionTest="false">
<test-code>
<description>(J8+) False negative for Java8+ and ternary operator (#2545)</description>
<expected-problems>2</expected-problems>
<expected-linenumbers>7,7</expected-linenumbers>