Add an option to reuse values captured from ref to search a tag

README.md

@@ -112,6 +112,17 @@ You can configure the version and properties adjustments for specific branches a
       - `<describeTagPattern>` An arbitrary regex to match tag names for git describe command
         - has to be a **full match pattern** e.g. `v.+`)
         - will override global `<describeTagPattern>` value
+        - can contain placeholders with `{{}}` delimiters that can be from env, properties, project version, or ref, but
+          not from `describe`. For example:
+          ```xml
+          <ref type="branch">
+            <pattern><![CDATA[release/(?<major>\d+)\.(?<minor>\d+)(?:\.x)?]]></pattern>
+            <describeTagPattern>\Qrelease-marker-{{ref.major}}.{{ref.minor}}\E</describeTagPattern>
+            <version>${ref.major}.${ref.minor}.0-rc.${describe.distance}-SNAPSHOT</version>
+          </ref>
+          ```
+          will first read the major and minor part of the version from the branch name, then will try to find a tag that
+          matches this specific version pieces to set the final version using describe.
       - `<describeTagFirstParent>` Enable(`true`) or disable(`false`) following only the first parent in a merge commit
         - default is `true`
           <br><br>

src/main/java/me/qoomon/gitversioning/commons/GitSituation.java

@@ -32,7 +32,9 @@ public class GitSituation {
 
     private final Supplier<Boolean> clean = Lazy.by(this::clean);
 
-    private Pattern describeTagPattern = Pattern.compile(".*");
+    private Supplier<Pattern> describeTagPattern = Lazy.by(() -> Pattern.compile(".*"));
+
+    private String rawDescribeTagPattern = ".*";
 
     private boolean firstParent = true;
 
@@ -121,13 +123,28 @@ public boolean isClean() {
         return clean.get();
     }
 
-    public void setDescribeTagPattern(Pattern describeTagPattern) {
+    /**
+     * Returns the describeTagPattern as set in config. It may contain placeholders delimited by <code>{{}}</code>,
+     * e.g. <code>{{ref.myCaptureGroupFromRef}}</code>. In order to get placeholder resolved,
+     * {@link GitSituation#getDescribeTagPattern()} should be used.
+     *
+     * @return the raw expressing for describe tag pattern
+     */
+    public String getRawDescribeTagPattern() {
+        return rawDescribeTagPattern;
+    }
+
+    public void setRawDescribeTagPattern(String rawDescribeTagPattern) {
+        this.rawDescribeTagPattern = requireNonNull(rawDescribeTagPattern);
+    }
+
+    public void setDescribeTagPattern(Supplier<Pattern> describeTagPattern) {
         this.describeTagPattern = requireNonNull(describeTagPattern);
         this.description = Lazy.by(this::describe);
     }
 
     public Pattern getDescribeTagPattern() {
-        return describeTagPattern;
+        return describeTagPattern.get();
     }
 
     public boolean isFirstParent() {
@@ -163,6 +180,6 @@ private boolean clean() throws GitAPIException {
     }
 
     private GitDescription describe() throws IOException {
-        return GitUtil.describe(head, describeTagPattern, repository, firstParent);
+        return GitUtil.describe(head, describeTagPattern.get(), repository, firstParent);
     }
 }

src/main/java/me/qoomon/maven/gitversioning/Configuration.java

@@ -48,13 +48,6 @@ public Pattern projectVersionPattern() {
 
     public Boolean describeTagFirstParent = true;
 
-    public Pattern describeTagPattern() {
-        if(describeTagPattern == null) {
-            return null;
-        }
-        return Pattern.compile(describeTagPattern);
-    }
-
     public Boolean updatePom = false;
 
     public RefPatchDescriptionList refs = new RefPatchDescriptionList();
@@ -72,13 +65,6 @@ public static class PatchDescription {
         @JsonDeserialize(using = IgnoreWhitespaceDeserializer.class)
         public String describeTagPattern;
 
-        public Pattern describeTagPattern() {
-            if(describeTagPattern == null) {
-                return null;
-            }
-            return Pattern.compile(describeTagPattern);
-        }
-
         @JsonDeserialize(using = IgnoreWhitespaceDeserializer.class)
         public String version;
 

src/main/java/me/qoomon/maven/gitversioning/GitVersioningModelProcessor.java

@@ -8,6 +8,7 @@
 import me.qoomon.gitversioning.commons.GitDescription;
 import me.qoomon.gitversioning.commons.GitSituation;
 import me.qoomon.gitversioning.commons.Lazy;
+import me.qoomon.gitversioning.commons.StringUtil;
 import me.qoomon.maven.gitversioning.Configuration.PatchDescription;
 import me.qoomon.maven.gitversioning.Configuration.RefPatchDescription;
 import org.apache.maven.building.Source;
@@ -49,7 +50,8 @@
 import static java.util.Objects.requireNonNullElse;
 import static java.util.stream.Collectors.*;
 import static me.qoomon.gitversioning.commons.GitRefType.*;
-import static me.qoomon.gitversioning.commons.StringUtil.*;
+import static me.qoomon.gitversioning.commons.StringUtil.patternGroupValues;
+import static me.qoomon.gitversioning.commons.StringUtil.substituteText;
 import static me.qoomon.maven.gitversioning.BuildProperties.projectArtifactId;
 import static me.qoomon.maven.gitversioning.GitVersioningMojo.asPlugin;
 import static me.qoomon.maven.gitversioning.MavenUtil.*;
@@ -67,6 +69,7 @@
 public class GitVersioningModelProcessor implements ModelProcessor {
 
     private static final Pattern VERSION_PATTERN = Pattern.compile(".*?(?<version>(?<core>(?<major>\\d+)(?:\\.(?<minor>\\d+)(?:\\.(?<patch>\\d+))?)?)(?:-(?<label>.*))?)|");
+    private static final Pattern PATTERN_PLACEHOLDERS_EXPRESSION = Pattern.compile("\\{\\{((?!describe\\.?)[^}]+)}}");
 
     private static final String OPTION_NAME_GIT_REF = "git.ref";
     private static final String OPTION_NAME_GIT_TAG = "git.tag";
@@ -228,9 +231,14 @@ private void init(Model projectModel) throws IOException {
         logger.info("matching ref: {} - {}", gitVersionDetails.getRefType().name(), gitVersionDetails.getRefName());
         final RefPatchDescription patchDescription = gitVersionDetails.getPatchDescription();
         logger.info("ref configuration: {} - pattern: {}", gitVersionDetails.getRefType().name(), patchDescription.pattern);
+
+        final Supplier<Map<String, Supplier<String>>> placeholderMapSupplier =
+                Lazy.by(() -> generateGlobalFormatPlaceholderMap(gitSituation, gitVersionDetails, mavenSession));
+
         if (patchDescription.describeTagPattern != null && !patchDescription.describeTagPattern.equals(".*")) {
             logger.info("  describeTagPattern: {}", patchDescription.describeTagPattern);
-            gitSituation.setDescribeTagPattern(patchDescription.describeTagPattern());
+            gitSituation.setRawDescribeTagPattern(patchDescription.describeTagPattern);
+            gitSituation.setDescribeTagPattern(preProcessDescribeTagPattern(patchDescription.describeTagPattern, placeholderMapSupplier));
         }
         if (patchDescription.describeTagFirstParent != null) {
             logger.info("  describeTagFirstParent: {}", patchDescription.describeTagFirstParent);
@@ -244,7 +252,7 @@ private void init(Model projectModel) throws IOException {
             patchDescription.properties.forEach((key, value) -> logger.info("    {} - {}", key, value));
         }
 
-        globalFormatPlaceholderMap = generateGlobalFormatPlaceholderMap(gitSituation, gitVersionDetails, mavenSession);
+        globalFormatPlaceholderMap = placeholderMapSupplier.get();
 
         if (!patchDescription.userProperties.isEmpty()) {
             logger.info("  userProperties: ");
@@ -835,6 +843,12 @@ private String getGitPropertyValue(String propertyFormat, String originalValue,
         return substituteText(propertyFormat, placeholderMap);
     }
 
+    private static Set<String> extractTagPatternGroups(String describeTagPattern) {
+        final Matcher placeHolderMatcher = PATTERN_PLACEHOLDERS_EXPRESSION.matcher(describeTagPattern);
+        final String placeHolderStrippedPattern = placeHolderMatcher.replaceAll("");
+        return StringUtil.patternGroups(Pattern.compile(placeHolderStrippedPattern));
+    }
+
     private Map<String, Supplier<String>> generateFormatPlaceholderMap(String projectVersion) {
         final Map<String, Supplier<String>> placeholderMap = new HashMap<>(globalFormatPlaceholderMap);
 
@@ -978,7 +992,7 @@ private Map<String, Supplier<String>> generateGlobalFormatPlaceholderMap(GitSitu
         // describe tag pattern groups
         final Lazy<Map<String, String>> describeTagPatternValues = Lazy.by(
                 () -> patternGroupValues(gitSituation.getDescribeTagPattern(), descriptionTag.get()));
-        for (String groupName : patternGroups(gitSituation.getDescribeTagPattern())) {
+        for (String groupName : extractTagPatternGroups(gitSituation.getRawDescribeTagPattern())) {
             final var placeholderKey = "describe.tag." + groupName;
             // ensure no placeholder overwrites
             if (placeholderMap.containsKey(placeholderKey)) {
@@ -1080,6 +1094,26 @@ private boolean getUpdatePomOption(final PatchDescription gitRefConfig) {
         return false;
     }
 
+    private Supplier<Pattern> preProcessDescribeTagPattern(String describeTagPattern, Supplier<Map<String, Supplier<String>>> placeholderMapSupplier) {
+        return Lazy.by(() -> {
+            final Matcher placeHolderMatcher = PATTERN_PLACEHOLDERS_EXPRESSION.matcher(describeTagPattern);
+            final StringBuilder sb = new StringBuilder();
+            while (placeHolderMatcher.find()) {
+                final String capture = placeHolderMatcher.group(1);
+                if (placeholderMapSupplier.get().containsKey(capture)) {
+                    final String value = placeholderMapSupplier.get().get(capture).get();
+                    placeHolderMatcher.appendReplacement(sb, value);
+                }
+            }
+            placeHolderMatcher.appendTail(sb);
+            final String pattern = sb.toString();
+            if (!describeTagPattern.equals(pattern)) {
+                logger.info("Computed pattern '{}' from describeTagPattern '{}'", pattern, describeTagPattern);
+            }
+            return Pattern.compile(pattern);
+        });
+    }
+
     // ---- determine related projects ---------------------------------------------------------------------------------
 
     private Set<GAV> determineRelatedProjects(Model projectModel) throws IOException {

src/test/java/me/qoomon/maven/gitversioning/GitVersioningExtensionIT.java

@@ -215,6 +215,61 @@ void tagVersioning_atBranch() throws Exception {
         }
     }
 
+    @Test
+    void tagVersioning_atBranch_extendedTagDescriptionFromSituation() throws Exception {
+
+        try (Git git = Git.init().setInitialBranch("master").setDirectory(projectDir.toFile()).call()) {
+            // Given
+            git.commit().setMessage("initial commit").setAllowEmpty(true).call();
+            git.tag().setAnnotated(true).setName("v1.0.0").call();
+
+            git.checkout().setName("release/2.3").setCreateBranch(true).call();
+            git.commit().setMessage("release commit").setAllowEmpty(true).call();
+
+            writeModel(projectDir.resolve("pom.xml").toFile(), pomModel);
+            writeExtensionsFile(projectDir);
+
+            final RefPatchDescription tagRef = createVersionDescription(TAG, "${ref.version}");
+            tagRef.pattern = "v(?<version>\\d+\\.\\d+\\.\\d+(?<preRelease>-(?:alpha|beta|rc)\\.\\d+)?)";
+
+            final RefPatchDescription releaseBranchRef = createVersionDescription(BRANCH, "${ref.major}.${ref.minor}.0-rc.${describe.distance}-SNAPSHOT");
+            releaseBranchRef.pattern = "release/(?<major>\\d+)\\.(?<minor>\\d+)(?:\\.x)?";
+            releaseBranchRef.describeTagPattern = "\\Qrelease-marker-{{ref.major}}.{{ref.minor}}\\E";
+
+            writeExtensionConfigFile(projectDir, new Configuration() {{
+                refs.considerTagsOnBranches = true;
+                refs.list.add(tagRef);
+                refs.list.add(releaseBranchRef);
+            }});
+
+            verifyOutputVersion("2.3.0-rc.2-SNAPSHOT");
+
+            // When
+            git.tag().setAnnotated(true).setName("release-marker-2.3").call();
+            git.commit().setMessage("new commit on release branch commit").setAllowEmpty(true).call();
+
+            //Then
+            verifyOutputVersion("2.3.0-rc.1-SNAPSHOT");
+
+            // When
+            git.commit().setMessage("another commit on release branch commit").setAllowEmpty(true).call();
+
+            //Then
+            verifyOutputVersion("2.3.0-rc.2-SNAPSHOT");
+        }
+    }
+
+    private void verifyOutputVersion(final String outputVersion) throws VerificationException, IOException {
+        Verifier verifier = getVerifier(projectDir);
+        verifier.addCliArgument("verify");
+        verifier.execute();
+        System.err.println(String.join("\n", verifier.loadFile(verifier.getBasedir(), verifier.getLogFileName(), false)));
+        verifier.verifyErrorFreeLog();
+        verifier.verifyTextInLog("Building " + pomModel.getArtifactId() + " " + outputVersion);
+        Model gitVersionedPomModel = readModel(projectDir.resolve(GIT_VERSIONING_POM_NAME).toFile());
+        assertThat(gitVersionedPomModel.getVersion()).isEqualTo(outputVersion);
+    }
+
     @Test
     void tagVersioning_detachedHead() throws Exception {