Merge pull request #331 from TheSnoozer/feature/214

#214 Introduce checkstyle to deploy a common code style

Author: TheSnoozer

.checkstyle

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<fileset-config file-format-version="1.2.0" simple-config="true" sync-formatter="false">
+  <local-check-config name="git-commit-id-plugin" location="src/test/resources/checks/google_checks_checkstyle_8.2.xml" type="project" description="">
+    <additional-data name="protect-config-file" value="false"/>
+  </local-check-config>
+  <fileset name="all" enabled="true" check-config-name="git-commit-id-plugin" local="true">
+    <file-match-pattern match-pattern="." include-pattern="true"/>
+  </fileset>
+</fileset-config>

.travis.yml

@@ -1,6 +1,12 @@
 language: java
 sudo: false
 dist: trusty
+
+stages:
+  - checkstyle
+  - test
+  - Integration Test
+
 jdk:
   - oraclejdk9
   - oraclejdk8
@@ -21,6 +27,14 @@ matrix:
     env: CUSTOM_MVN_VERION="3.3.9"
   - jdk: oraclejdk9
     env: CUSTOM_MVN_VERION="3.5.0"
+  - stage: checkstyle
+    jdk: oraclejdk9
+    script: mvn clean verify -Pcheckstyle -Dcheckstyle.version=8.2 -Dmaven.test.skip=true -B
+    env: CHECKSTYLE=8.2
+  - stage: checkstyle
+    jdk: openjdk7
+    script: mvn clean verify -Pcheckstyle -Dmaven.test.skip=true -B
+    env: CHECKSTYLE=6.11.2
 
 install:
   - if [[ -n "${CUSTOM_MVN_VERION}" ]]; then

README.md

@@ -41,7 +41,7 @@ In order to understand the ideology and intention here are some pretty usefull i
 With the current version of the validation the user can decide if the build should fail if *at least one* of the defined criterias do not match with the desired values.
 
 For flexibility and due to the fact that this validation has a different scope than the maven-git-commit-id-plugin this validation needs to be configured as additional execution inside the configuration of the pom.xml.
-Once configured, the validation is executed during the verification-phase. However since the validation is done in a seperate execution the phase can easily be changed by adding the desired phase to the execution configuration.
+Once configured, the validation is executed during the verification-phase. However since the validation is done in a separate execution the phase can easily be changed by adding the desired phase to the execution configuration.
 
 Usage Example:
 
@@ -72,7 +72,7 @@ Usage Example:
 
 Required Configuration:
 If you plan to use this feature you'll want to know that the validation will be executed inside an additional mojo.
-Inside you pom you thus may want to add an additional execution tag that triggers the execution of the validation plugin.
+Inside your pom you thus may want to add an additional execution tag that triggers the execution of the validation plugin.
 You can also change the default phase of each execution by adding a `phase` definition.
 
 ```xml
@@ -191,7 +191,7 @@ It's really simple to setup this plugin; below is a sample pom that you may base
             <plugin>
                 <groupId>pl.project13.maven</groupId>
                 <artifactId>git-commit-id-plugin</artifactId>
-                <version>2.2.1</version>
+                <version>2.2.3</version>
                 <executions>
                     <execution>
                         <id>get-the-git-infos</id>
@@ -362,7 +362,7 @@ It's really simple to setup this plugin; below is a sample pom that you may base
                         The token can be seen as the needle and the value as the text to be written over any found tokens. If using regular expressions the value can reference grouped regex matches by using $1, $2, etc.
 
                         Since 2.2.4 the plugin allows to define a even more sophisticated ruleset and allows to set an `propertyOutputSuffix` within each replacement property. If this option is empty the original property will be overwritten (default behaviour in 2.2.3). however when this configuration is set to `something` and a user wants to modify the `git.branch` property the plugin will keep `git.branch` as the original one (w/o modifications) but also will be creating a new `git.branch.something` property with the requested replacement.
-                        Furthermore with 2.2.4 the plugin allows to perform certain types of string manipulation either before or after the evaluation of the replacement. With this feature a user can currently easily manipulate the case (e.g. lower case VS upper case) of the input/output property. This behaviour can be achieved by defining a list of `transformationRules` for the property where those rules should take effect. Each `transformationRule` consist of two required fields `apply` and `action`. The `apply`-tag controls when the rule should be applied and can be set to `BEFORE` to have the rule being applied before or it can be set to `AFTER` to have the rule being applied after the replacement. The `action`-tag determines the string conversion rule that should be applied. Currenlty supported is `LOWER_CASE` and `UPPER_CASE`. Potential candidates in the feature are `CAPITALIZATION` and `INVERT_CASE``(open a ticket if you need them...).
+                        Furthermore with 2.2.4 the plugin allows to perform certain types of string manipulation either before or after the evaluation of the replacement. With this feature a user can currently easily manipulate the case (e.g. lower case VS upper case) of the input/output property. This behaviour can be achieved by defining a list of `transformationRules` for the property where those rules should take effect. Each `transformationRule` consist of two required fields `apply` and `action`. The `apply`-tag controls when the rule should be applied and can be set to `BEFORE` to have the rule being applied before or it can be set to `AFTER` to have the rule being applied after the replacement. The `action`-tag determines the string conversion rule that should be applied. Currently supported is `LOWER_CASE` and `UPPER_CASE`. Potential candidates in the feature are `CAPITALIZATION` and `INVERT_CASE``(open a ticket if you need them...).
 
                         Please note that the replacement will *only be applied to properties that are being generated by the plugin*.
                         If you want to replace properties that are being generated by other plugins you may want to use the maven-replacer-plugin or any other alternative.
@@ -766,7 +766,7 @@ git.build.time=${git.build.time}
 Yet another way to use the plugin
 =================================
 
-Rather than reading properties files at runtime or injecting with spring, you can filter a Java source file directly and place it into src/main/java with an ignore, or into generated sources directory within the target directory. This has some minor advantages and disadvantages, but is useful for avoiding runtime injection or lookup from properties files that might get lost during repackaging later if used within a library. 
+Rather than reading properties files at runtime or injecting with spring, you can filter a Java source file directly and place it into `src/main/java` with an ignore, or into generated sources directory within the target directory. This has some minor advantages and disadvantages, but is useful for avoiding runtime injection or lookup from properties files that might get lost during repackaging later if used within a library.
 
 Git describe - short intro to an awesome command
 ==================================================
@@ -939,6 +939,22 @@ Example:
 If you are using the maven build with [Maven's Plugin Prefix Resolution](https://maven.apache.org/guides/introduction/introduction-to-plugin-prefix-mapping.html) (e.g. `mvn somePrefix:goal`) please note that this currently seems to be [not supported by maven](https://issues.apache.org/jira/browse/MNG-6260).
 Instead of using the Plugin Prefix Resolution add an execution tag that calls the desired goal of the plugin within a normal maven life cycle (e.g. `mvn clean package`).
 
+How to contribute to the project
+-------------------------------
+In general pull requests and support for open issues is always welcome!
+If you open a pull request or want to help out in any way please keep in mind that we currently use `checkstyle` to ensure that the project somehow maintains a uniform code base. Fortunately the most common IDEs support the integration of `checkstyle` via plugins. On top of more or less native integration into modern development tools the `checkstyle` rules are currently also being verified by using the [maven-checkstyle-plugin](https://maven.apache.org/plugins/maven-checkstyle-plugin/) during the build. it should be worth to highlight that you are not required to install `checkstyle` inside your IDE. If you feel more comfortable running the checks via maven this would to the trick!
+The checkstyle rules for this project are currently residing in `src/test/resources/checks` and for some IDEs those rules need to be imported manually (unfortunately there is no better solution available for this yet). The current rule set is pretty much the same as the `google_checks.xml` with certain checks disabled (e.g. line length). If you choose to integrate `checkstyle` inside your IDE feel free to checkout some high level requirements to get started with checkstyle within your IDE:
+* eclipse -- for eclipse / STS you would need to install the `checkstyle plug-in` via `Help -> Eclipse Marketplace -> Search` after restarting eclipse it should pick-up the rules automatically. If this does not work out of the box checkout the [official integration guide](http://checkstyle.sourceforge.net/eclipse.html) or use google to trace down your error message.
+* IntelliJ IDEA -- for IntelliJ you would need to install the `CheckStyle-IDEA` via `File -> Settings -> Plugins -> Search`. After restarting IntelliJ you would need to import the `checkstyle` rules manually via `File -> Settings -> Checkstyle`. As checkstyle version you may choose `6.11.2` or `8.2` and then click on the plus-sign on the right. As description you may choose `maven-git-commit-id-plugin` and as local checkstyle file you may choose one of the checkstyle rule residing in `src/test/resources/checks`. Please note that the rule-file depend on the version you have selected in the previous step and thus it is essential to ensure that the version numbers match up. As next-step you unfortunately will be prompted to enter the **full directory** of the `checkstyle-suppressions.xml`-File. If this does not work out of the box checkout the [official integration guide](http://checkstyle.sourceforge.net/idea.html) or use google to trace down your error message.
+* Netbeans -- feel free to open a ticket and share your installation guide :-) You can also check out the [official integration guide](http://checkstyle.sourceforge.net/netbeans.html) or use google to get any addtional help.
+* Maven -- if you want to run `checkstyle` via maven you simply can execute `mvn clean verify -Pcheckstyle -Dmaven.test.skip=true -B`. If you are using java9 you may want to run `mvn clean verify -Pcheckstyle -Dcheckstyle.version=8.2 -Dmaven.test.skip=true -B` that uses a more recent checkstyle version.
+
+**Note**:
+If you run into
+```
+[ERROR] Failed to execute goal org.apache.maven.plugins:maven-checkstyle-plugin:2.17:check (validate) on project git-commit-id-plugin: Execution validate of goal org.apache.maven.plugins:maven-checkstyle-plugin:2.17:check failed: Plugin org.apache.maven.plugins:maven-checkstyle-plugin:2.17 or one of its dependencies could not be resolved: Could not find artifact com.sun:tools:jar:1.7.0 at specified path /usr/lib/jvm/java-9-oracle/../lib/tools.jar -> [Help 1]
+```
+you may want to check that your ``JAVA_HOME``-Path is set correctly and that your are running `mvn clean verify -Pcheckstyle -Dcheckstyle.version=8.2 -Dmaven.test.skip=true -B`.
 
 Maintainers
 ===========
@@ -953,7 +969,7 @@ I'd like to give a big thanks to some of these folks, for their suggestions and
 * @fredcooke - for consistent feedback and suggestions,
 * @MrOnion - for a small yet fast bugfix,
 * @cardil and @TheSnoozer - for helping with getting the native git support shipped,
-* all the other contributors (as of writing 25) which can be on the [contributors tab](https://github.com/ktoso/maven-git-commit-id-plugin/graphs/contributors) - thanks guys,
+* all the other contributors (as of writing 50) which can be on the [contributors tab](https://github.com/ktoso/maven-git-commit-id-plugin/graphs/contributors) - thanks guys,
 * ... many others - thank you for your contributions,
 * ... you! - for using the plugin :-)
 

pom.xml

@@ -419,5 +419,59 @@
         </plugins>
       </build>
     </profile>
+    <profile>
+      <id>checkstyle</id>
+      <properties>
+        <maven-checkstyle-plugin.version>2.17</maven-checkstyle-plugin.version>
+        <!--  if you update the checkstyle version make sure you update the google_checks.xml inside the repository -->
+        <checkstyle.version>6.11.2</checkstyle.version>
+      </properties>
+      <build>
+        <pluginManagement>
+          <plugins>
+            <plugin>
+              <groupId>org.apache.maven.plugins</groupId>
+              <artifactId>maven-checkstyle-plugin</artifactId>
+              <version>${maven-checkstyle-plugin.version}</version>
+              <dependencies>
+                <dependency>
+                  <groupId>com.puppycrawl.tools</groupId>
+                  <artifactId>checkstyle</artifactId>
+                  <version>${checkstyle.version}</version>
+                </dependency>
+              </dependencies>
+            </plugin>
+          </plugins>
+        </pluginManagement>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-checkstyle-plugin</artifactId>
+            <version>${maven-checkstyle-plugin.version}</version>
+            <executions>
+              <execution>
+                <id>validate</id>
+                <phase>verify</phase>
+                <goals>
+                  <goal>check</goal>
+                </goals>
+                <configuration>
+                  <configLocation>${basedir}/src/test/resources/checks/google_checks_checkstyle_${checkstyle.version}.xml</configLocation>
+                  <suppressionsLocation>${basedir}/src/test/resources/checks/checkstyle-suppressions.xml</suppressionsLocation>
+                  <propertyExpansion>samedir=${basedir}/src/test/resources/checks</propertyExpansion>
+                  <includeTestSourceDirectory>true</includeTestSourceDirectory>
+                  <encoding>${project.reporting.outputEncoding}</encoding>
+                  <consoleOutput>true</consoleOutput>
+                  <violationSeverity>warning</violationSeverity>
+                  <failsOnError>true</failsOnError>
+                  <failOnViolation>true</failOnViolation>
+                  <linkXRef>false</linkXRef>
+               </configuration>
+              </execution>
+            </executions>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
   </profiles>
 </project>

src/main/java/pl/project13/jgit/DescribeCommand.java

@@ -47,12 +47,12 @@ public class DescribeCommand extends GitCommand<DescribeResult> {
   private LoggerBridge log;
   private JGitCommon jGitCommon;
 
-//  TODO not yet implemented options:
-//  private boolean containsFlag = false;
-//  private boolean allFlag = false;
-//  private boolean tagsFlag = false;
-//  private Optional<Integer> candidatesOption = Optional.of(10);
-//  private boolean exactMatchFlag = false;
+  //  TODO not yet implemented options:
+  //  private boolean containsFlag = false;
+  //  private boolean allFlag = false;
+  //  private boolean tagsFlag = false;
+  //  private Optional<Integer> candidatesOption = Optional.of(10);
+  //  private boolean exactMatchFlag = false;
 
   private Optional<String> matchOption = Optional.absent();
 
@@ -275,7 +275,7 @@ public DescribeResult call() throws GitAPIException {
     List<RevCommit> commits;
     try {
       commits = jGitCommon.findCommitsUntilSomeTag(repo, headCommit, tagObjectIdToName);
-    } catch(Exception e) {
+    } catch (Exception e) {
       if (alwaysFlag) {
         // Show uniquely abbreviated commit object as fallback
         commits = Collections.emptyList();
@@ -360,12 +360,12 @@ RevCommit findHeadObjectId(@NotNull Repository repo) throws RuntimeException {
 
   // git commit id -> its tag (or tags)
   private Map<ObjectId, List<String>> findTagObjectIds(@NotNull Repository repo, boolean tagsFlag) {
-	  String matchPattern = createMatchPattern();
-	  Map<ObjectId, List<DatedRevTag>> commitIdsToTags = jGitCommon.getCommitIdsToTags(repo, tagsFlag, matchPattern);
-      Map<ObjectId, List<String>> commitIdsToTagNames = jGitCommon.transformRevTagsMapToDateSortedTagNames(commitIdsToTags);
+    String matchPattern = createMatchPattern();
+    Map<ObjectId, List<DatedRevTag>> commitIdsToTags = jGitCommon.getCommitIdsToTags(repo, tagsFlag, matchPattern);
+    Map<ObjectId, List<String>> commitIdsToTagNames = jGitCommon.transformRevTagsMapToDateSortedTagNames(commitIdsToTags);
     log.info("Created map: [{}]", commitIdsToTagNames);
 
-      return commitIdsToTagNames;
+    return commitIdsToTagNames;
   }
 
   private String createMatchPattern() {

src/main/java/pl/project13/jgit/DescribeResult.java

@@ -20,17 +20,16 @@
 import com.google.common.base.Joiner;
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
-import org.eclipse.jgit.lib.AbbreviatedObjectId;
-import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectReader;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import org.eclipse.jgit.lib.AbbreviatedObjectId;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.ObjectReader;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 /**
  * Represents the result of a <code>git describe</code> command.