feat(INFRA-2150): Add checkstyle-without-formatting.xml

[rschmitz-circle]

Summary

Add a checkstyle config that doesn't overlap with Spotless.

Detail

Senior ICs group has officially endorsed using Spotless for automated formatting going forward. Using Spotless is optional, not required. This PR provides an alternate checkstyle config for repos which have adopted Spotless. This checkstyle config removes overlap between Checkstyle and Spotless, preventing conflicts between the tools.

The new config is a copy of the existing config but with whitespace formatting removed. For convenience, the diff is given here:

diff --git a/./checkstyle-circle.xml b/./checkstyle-without-formatting.xml
index a79edd9..feaff89 100644
--- a/./checkstyle-circle.xml
+++ b/./checkstyle-without-formatting.xml

+<!--
+   This file matches the default checkstyle-circle.xml configuration, but removes all
+   formatting rules that are covered by a code formatter (such as Palantir or Google)
  -->
 
@@ -59,91 +53,35 @@
-        <module name="NoLineWrap"/>
-        <module name="LeftCurly"/>
-        <module name="RightCurly">
-            <property name="id" value="RightCurlySame"/>
-            <property name="tokens"
-             value="LITERAL_TRY, LITERAL_CATCH, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE,
-                    LITERAL_DO"/>
-        </module>
-        <module name="RightCurly">
-            <property name="id" value="RightCurlyAloneOrSingleLine"/>
-            <property name="option" value="alone_or_singleline"/>
-            <property name="tokens" value="CLASS_DEF, CTOR_DEF, INSTANCE_INIT, LITERAL_FOR, LITERAL_WHILE, METHOD_DEF, STATIC_INIT"/>
-        </module>
-        <module name="WhitespaceAround">
-            <property name="allowEmptyConstructors" value="true"/>
-            <property name="allowEmptyMethods" value="true"/>
-            <property name="allowEmptyTypes" value="true"/>
-            <property name="allowEmptyLambdas" value="true"/>
-            <property name="allowEmptyLoops" value="true"/>
-            <message key="ws.notFollowed"
-             value="WhitespaceAround: ''{0}'' is not followed by whitespace. Empty blocks may only be represented as '{}' when not part of a multi-block statement (4.1.3)"/>
-            <message key="ws.notPreceded"
-             value="WhitespaceAround: ''{0}'' is not preceded with whitespace."/>
-        </module>
-        <module name="OneStatementPerLine"/>
-        <module name="ModifierOrder"/>
-        <module name="EmptyLineSeparator">
-            <property name="allowNoEmptyLineBetweenFields" value="true"/>
-        </module>
-        <module name="SeparatorWrap">
-            <property name="id" value="SeparatorWrapDot"/>
-            <property name="tokens" value="DOT"/>
-            <property name="option" value="nl"/>
-        </module>
-        <module name="SeparatorWrap">
-            <property name="id" value="SeparatorWrapComma"/>
-            <property name="tokens" value="COMMA"/>
-            <property name="option" value="EOL"/>
-        </module>
-        <module name="SeparatorWrap">
-            <!-- ELLIPSIS is EOL until https://github.com/google/styleguide/issues/258 -->
-            <property name="id" value="SeparatorWrapEllipsis"/>
-            <property name="tokens" value="ELLIPSIS"/>
-            <property name="option" value="EOL"/>
-        </module>
-        <module name="SeparatorWrap">
-            <!-- ARRAY_DECLARATOR is EOL until https://github.com/google/styleguide/issues/259 -->
-            <property name="id" value="SeparatorWrapArrayDeclarator"/>
-            <property name="tokens" value="ARRAY_DECLARATOR"/>
-            <property name="option" value="EOL"/>
-        </module>
-        <module name="SeparatorWrap">
-            <property name="id" value="SeparatorWrapMethodRef"/>
-            <property name="tokens" value="METHOD_REF"/>
-            <property name="option" value="nl"/>
-        </module>
-        <module name="GenericWhitespace">
-            <message key="ws.followed"
-             value="GenericWhitespace ''{0}'' is followed by whitespace."/>
-            <message key="ws.preceded"
-             value="GenericWhitespace ''{0}'' is preceded with whitespace."/>
-            <message key="ws.illegalFollow"
-             value="GenericWhitespace ''{0}'' should followed by whitespace."/>
-            <message key="ws.notPreceded"
-             value="GenericWhitespace ''{0}'' is not preceded with whitespace."/>
-        </module>
-        <module name="Indentation">
-            <property name="basicOffset" value="4"/>
-            <property name="braceAdjustment" value="0"/>
-            <property name="caseIndent" value="4"/>
-            <property name="throwsIndent" value="4"/>
-            <property name="lineWrappingIndentation" value="4"/>
-            <property name="arrayInitIndent" value="4"/>
-        </module>
-        <module name="CustomImportOrder">
-            <property name="customImportOrderRules"
-            value="THIRD_PARTY_PACKAGE###SPECIAL_IMPORTS###STANDARD_JAVA_PACKAGE###STATIC"/>
-            <property name="specialImportsRegExp" value="^javax\."/>
-            <property name="standardPackageRegExp" value="^java\."/>
-            <property name="sortImportsInGroupAlphabetically" value="true"/>
-            <property name="separateLineBetweenGroups" value="false"/>
-        </module>
-        <module name="UnusedImports"/>
-        <module name="MethodParamPad"/>
-        <module name="NoWhitespaceBefore">
-            <property name="tokens"
-             value="COMMA, SEMI, POST_INC, POST_DEC, DOT, ELLIPSIS, METHOD_REF"/>
-            <property name="allowLineBreaks" value="true"/>
-        </module>
-        <module name="ParenPad"/>
-        <module name="OperatorWrap">
-            <property name="option" value="NL"/>
-            <property name="tokens"
-             value="BAND, BOR, BSR, BXOR, DIV, EQUAL, GE, GT, LAND, LE, LITERAL_INSTANCEOF, LOR,
-                    LT, MINUS, MOD, NOT_EQUAL, QUESTION, SL, SR, STAR, METHOD_REF "/>
-        </module>
-        <module name="AnnotationLocation">
-            <property name="id" value="AnnotationLocationMostCases"/>
-            <property name="tokens"
-             value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF"/>
-        </module>
-        <module name="AnnotationLocation">
-            <property name="id" value="AnnotationLocationVariables"/>
-            <property name="tokens" value="VARIABLE_DEF"/>
-            <property name="allowSamelineMultipleAnnotations" value="true"/>
-        </module>
-        <module name="CommentsIndentation"/>

Testing

Several repos (notably, transaction-core) have been using this exact config alongside Checkstyle for some time without issue.

Documentation

Automatically format code with Spotless: Using Alongside Checkstyle

Using SonarQube, Checkstyle, and Spotless

[pratgoyal]

Is this a copy of the Txcore checkstyle?

[mboorstin-circle]

Please wait to merge this until we finish a discussion about whether we are comfortable with the linked SonarQube changes.

[rschmitz-circle]

Is this a copy of the Txcore checkstyle?

exactly

[rschmitz-circle]

Please wait to merge this until we finish a discussion about whether we are comfortable with the linked SonarQube changes.

Sorry I don't follow - this isn't related to SQ, just checkstyle/spotless?

[mboorstin-circle]

Discussed over Slack; approving.