From 004588e71b280901364752cfd07934dffff5729f Mon Sep 17 00:00:00 2001
From: Simon Templer <simon@wetransform.to>
Date: Sat, 30 Mar 2024 00:57:08 +0100
Subject: [PATCH] feat: verify if tag(s) represent release version

---
 README.md                                     |  7 +++--
 .../gradle/version/VersionExtension.groovy    | 20 +++++++++++++
 .../gradle/version/VersionPlugin.groovy       | 28 ++++++++++++-------
 3 files changed, 43 insertions(+), 12 deletions(-)

diff --git a/README.md b/README.md
index 73c92a5..b25dcc1 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,10 @@ The plugin works based on the following assumptions:
 3. If the git repository is not clean or HEAD does not point to a tag, the project version is a SNAPSHOT version that increases the minor version compared to the last release version
 4. If no release version is configured or the version file is missing, the project version is `1.0.0-SNAPSHOT`
 
-If the environment variable `RELEASE` is set to `true`, the release version is used, even if the repository is not clean or there is no tag.
-This is intended for use cases where the release version was set, but the repository is dirty or no tag was created.
+For a tag to be recognized it needs to match the configured release version, optionally with the prefix `v`, for example `1.0.0` or `v1.0.0`.
+
+If the environment variable `RELEASE` is set to `true`, the release version is used, even if the repository is not clean.
+This is intended for use cases where the release version was set, but the repository is expected to be dirty, e.g. due to other CI tasks.
+A cleaner method is avoid the repository being dirty, e.g. by adding additional files that are created during the release process to `.gitignore` if possible.
 
 By default the version file is assumed to be the file `version.txt` in the root project.
diff --git a/src/main/groovy/to/wetransform/gradle/version/VersionExtension.groovy b/src/main/groovy/to/wetransform/gradle/version/VersionExtension.groovy
index 71645a8..8290a26 100644
--- a/src/main/groovy/to/wetransform/gradle/version/VersionExtension.groovy
+++ b/src/main/groovy/to/wetransform/gradle/version/VersionExtension.groovy
@@ -1,5 +1,6 @@
 package to.wetransform.gradle.version
 
+import java.util.function.BiPredicate
 import org.gradle.api.Project
 
 class VersionExtension {
@@ -9,8 +10,27 @@ class VersionExtension {
     this.gitDir = project.rootProject.projectDir
   }
 
+  /**
+   * Location of the file that holds the last release version, if it exists.
+   */
   File versionFile
 
+  /**
+   * Location of the git repository to check.
+   */
   File gitDir
 
+  /**
+   * Test to verify if a tag is a version tag and if the version matches the provided release version.
+   */
+  BiPredicate<String, String> verifyTag = { tag, version ->
+    def matcher = tag =~ /^v?((\d+)\.(\d+)\.(\d+))$/
+    if (matcher) {
+      matcher[0][1] == version
+    }
+    else {
+      false
+    }
+  }
+
 }
diff --git a/src/main/groovy/to/wetransform/gradle/version/VersionPlugin.groovy b/src/main/groovy/to/wetransform/gradle/version/VersionPlugin.groovy
index 7436b87..c3a6dda 100644
--- a/src/main/groovy/to/wetransform/gradle/version/VersionPlugin.groovy
+++ b/src/main/groovy/to/wetransform/gradle/version/VersionPlugin.groovy
@@ -1,5 +1,6 @@
 package to.wetransform.gradle.version;
 
+import java.util.function.BiPredicate
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 
@@ -53,12 +54,14 @@ class VersionPlugin implements Plugin<Project> {
       if(it.version != Project.DEFAULT_VERSION) {
         throw new IllegalStateException("Version may not be configured if version plugin is applied")
       } else {
-        it.version = determineVersion(it, it.versionConfig.versionFile, it.versionConfig.gitDir)
+        it.version = determineVersion(
+          it, it.versionConfig.versionFile, it.versionConfig.gitDir, it.versionConfig.verifyTag
+        )
       }
     }
   }
 
-  String determineVersion(Project project, File versionFile, File gitDir) {
+  String determineVersion(Project project, File versionFile, File gitDir, BiPredicate<String, String> verifyTag) {
     // read version from file
     def releaseVersion = null
     if (versionFile.exists()) {
@@ -79,11 +82,6 @@ class VersionPlugin implements Plugin<Project> {
       return '1.0.0-SNAPSHOT'
     }
 
-    if ('true'.equalsIgnoreCase(System.getenv('RELEASE'))) {
-      // force release version (e.g if repo is dirty during release in CI)
-      return releaseVersion
-    }
-
     def dirty = false
     def tagOnCurrentCommit = false
     def grgit
@@ -97,12 +95,22 @@ class VersionPlugin implements Plugin<Project> {
       dirty = !grgit.status().isClean()
       def currentCommit = grgit.head().id
       tagOnCurrentCommit = grgit.tag.list().findAll { tag ->
-        tag.commit.id == currentCommit
+        tag.commit.id == currentCommit && verifyTag.test(tag.name, releaseVersion)
+      }
+    }
+
+    if ('true'.equalsIgnoreCase(System.getenv('RELEASE'))) {
+      // force release version if repo is dirty (e.g. during release in CI)
+      // but still verify tag
+      if (tagOnCurrentCommit) {
+        return releaseVersion
+      }
+      else {
+        throw new IllegalStateException("There is no matching tag for the configured release version $releaseVersion")
       }
     }
+
     if (tagOnCurrentCommit && !dirty) {
-      //TODO check tags?
-      //XXX for now assume tag represents release
       project.logger.info("Current commit is tagged and repository clean, using release version specified in file: $releaseVersion")
       releaseVersion
     }