Use a lazy version object

- Change from generating a string up front to generating it upon first request using a lazy object and toString(). - Update Gradle plugin plugin versions
Widen · Feb 28, 2019 · ca5713e · ca5713e
1 parent af268d5
commit ca5713e
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Showing 5 changed files with 50 additions and 30 deletions.
diff --git a/build.gradle b/build.gradle
@@ -1,8 +1,8 @@
 plugins {
     id 'groovy'
-    id 'java'
-    id 'com.gradle.plugin-publish' version '0.9.10'
-    id 'com.widen.versioning' version '0.3.1'
+    id 'java-gradle-plugin'
+    id 'com.gradle.plugin-publish' version '0.10.1'
+    id 'com.widen.versioning' version '0.3.2'
 }
 
 group = 'com.widen.oss'
@@ -15,13 +15,21 @@ repositories {
 }
 
 dependencies {
-    compile gradleApi()
     compile 'commons-io:commons-io:2.6'
 
     testCompile 'org.codehaus.groovy:groovy-all:2.4.12'
     testCompile 'org.spockframework:spock-core:1.1-groovy-2.4'
 }
 
+gradlePlugin {
+    plugins {
+        versioningPlugin {
+            id = 'com.widen.versioning'
+            implementationClass = 'com.widen.versioning.VersioningPlugin'
+        }
+    }
+}
+
 pluginBundle {
     website = 'https://github.com/Widen/gradle-versioning'
     vcsUrl = 'https://github.com/Widen/gradle-versioning'

diff --git a/src/main/java/com/widen/versioning/VersionGenerator.java b/src/main/java/com/widen/versioning/VersionGenerator.java
@@ -5,16 +5,17 @@
 import java.io.File;
 import java.nio.charset.Charset;
 import java.util.ArrayList;
+import java.util.Optional;
 
 public class VersionGenerator {
-    public static String generateFromGit(Settings settings, File projectDir) {
-        String describe = gitDescribe(settings, projectDir);
-        return generateFromString(describe, settings);
+    public static Optional<String> generateFromGit(Settings settings, File projectDir) {
+        return gitDescribe(settings, projectDir)
+            .flatMap(describe -> generateFromString(describe, settings));
     }
 
-    public static String generateFromString(String describe, Settings settings) {
+    public static Optional<String> generateFromString(String describe, Settings settings) {
         if (describe == null) {
-            return null;
+            return Optional.empty();
         }
 
         String version = describe.trim().replaceFirst("-(\\d+-g.)", "+$1");
@@ -23,10 +24,10 @@ public static String generateFromString(String describe, Settings settings) {
             version = version.substring(settings.tagPrefix.length());
         }
 
-        return version;
+        return Optional.of(version);
     }
 
-    public static String gitDescribe(Settings settings, File projectDir) {
+    public static Optional<String> gitDescribe(Settings settings, File projectDir) {
         ArrayList<String> args = new ArrayList<>();
         args.add("git");
         args.add("describe");
@@ -63,11 +64,11 @@ public static String gitDescribe(Settings settings, File projectDir) {
             String output = IOUtils.toString(process.getInputStream(), Charset.forName("UTF-8"));
 
             process.waitFor();
-            if (process.exitValue() != 0 || output.isEmpty()) {
+            if (process.exitValue() != 0) {
                 throw new RuntimeException("Git returned status code " + process.exitValue() + ": " + output);
             }
 
-            return output;
+            return Optional.of(output).filter(s -> !s.isEmpty());
         }
         catch (Exception e) {
             throw new RuntimeException(e);

diff --git a/src/main/java/com/widen/versioning/VersioningPlugin.java b/src/main/java/com/widen/versioning/VersioningPlugin.java
@@ -12,28 +12,40 @@ public void apply(final Project project) {
 
         Task task = project.getTasks().create("printVersion");
         task.setGroup("Versioning");
-        task.setDescription("Prints the project\'s configured version");
+        task.setDescription("Prints the project's configured version");
         task.doLast(t -> System.out.println(project.getVersion()));
 
-        // Defer setting the version until after the build script is evaluated.
-        project.afterEvaluate(p -> applyVersion(project, settings));
+        project.setVersion(new LazyVersion(project, settings));
     }
 
-    private void applyVersion(final Project project, final Settings settings) {
-        String version = null;
-        try {
-            version = VersionGenerator.generateFromGit(settings, project.getRootProject().getProjectDir());
-        }
-        catch (Exception e) {
-            project.getLogger().warn("Error trying to determine project version", e);
+    private static class LazyVersion {
+        private final Project project;
+        private final Settings settings;
+        private String version;
+
+        private LazyVersion(Project project, Settings settings) {
+            this.project = project;
+            this.settings = settings;
         }
 
-        if (version != null) {
-            project.setVersion(version);
+        private String generateVersion() {
+            try {
+                return VersionGenerator
+                    .generateFromGit(settings, project.getRootProject().getProjectDir())
+                    .orElse(settings.initialVersion);
+            }
+            catch (Exception e) {
+                project.getLogger().warn("Error trying to determine project version", e);
+                return settings.initialVersion;
+            }
         }
-        else if ("unspecified".equals(project.getVersion())) {
-            project.getLogger().debug("No version specified, using initial version");
-            project.setVersion(settings.initialVersion);
+
+        @Override
+        public String toString() {
+            if (version == null) {
+                version = generateVersion();
+            }
+            return version;
         }
     }
 }
diff --git a/src/main/resources/META-INF/gradle-plugins/com.widen.versioning.properties b/src/main/resources/META-INF/gradle-plugins/com.widen.versioning.properties
diff --git a/src/test/groovy/com/widen/versioning/VersionGeneratorTest.groovy b/src/test/groovy/com/widen/versioning/VersionGeneratorTest.groovy
@@ -7,7 +7,7 @@ class VersionGeneratorTest extends Specification {
     @Unroll("git describe '#describe' should become '#version'")
     def "parse git describe to version"() {
         expect:
-        VersionGenerator.generateFromString(describe, new Settings(tagPrefix: prefix)) == version
+        VersionGenerator.generateFromString(describe, new Settings(tagPrefix: prefix)).orElse(null) == version
 
         where:
         prefix | describe           | version