From 68af3cd067381e079f15721e397e42c510c9e912 Mon Sep 17 00:00:00 2001
From: Konrad Malawski <ktoso@apple.com>
Date: Thu, 18 Jun 2026 12:53:22 +0900
Subject: [PATCH] Derive Maven version from `git describe --tags --always`

SwiftKitCore and SwiftKitFFM compute their Maven version directly from the
current checkout via `git describe --tags --always`. A checkout on an exact
SemVer tag (e.g. `0.4.2`) publishes that version; off-tag working trees
publish a tag-prefixed identifier such as `0.4.1-52-g8f0d0794`. This replaces
the previous hardcoded `1.0-SNAPSHOT` so Maven coordinates always reflect the
upstream commit a consumer pinned.
---
 .gitignore                                    |  3 ++
 BuildLogic/.gitignore                         |  2 +-
 .../org/swift/build/utils/gitVersion.kt       | 47 +++++++++++++++++++
 SwiftKitCore/build.gradle.kts                 |  8 ++--
 SwiftKitFFM/build.gradle.kts                  |  7 +--
 5 files changed, 60 insertions(+), 7 deletions(-)
 create mode 100644 BuildLogic/src/main/kotlin/org/swift/build/utils/gitVersion.kt

diff --git a/.gitignore b/.gitignore
index 01dc9f697..4a1ca5a72 100644
--- a/.gitignore
+++ b/.gitignore
@@ -25,6 +25,9 @@ BuildLogic/out/
 **/build/
 lib/
 
+# Though make sure we include actual sources, even if they are ignored because e.g. /build/ in the path
+!**/src/main/kotlin/**
+
 # Ignore JVM crash logs
 **/*.log
 
diff --git a/BuildLogic/.gitignore b/BuildLogic/.gitignore
index 91ea7410d..605e05406 100644
--- a/BuildLogic/.gitignore
+++ b/BuildLogic/.gitignore
@@ -1,2 +1,2 @@
-build
+/build/
 .gradle
diff --git a/BuildLogic/src/main/kotlin/org/swift/build/utils/gitVersion.kt b/BuildLogic/src/main/kotlin/org/swift/build/utils/gitVersion.kt
new file mode 100644
index 000000000..e4279d2c4
--- /dev/null
+++ b/BuildLogic/src/main/kotlin/org/swift/build/utils/gitVersion.kt
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2026 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+package org.swift.build.utils
+
+import org.gradle.api.Project
+
+/**
+ * Resolve the publication version for swift-java's Java artifacts.
+ *
+ * Resolution order:
+ * 1. `-PswiftkitVersion=<value>` project property, for CI/release overrides.
+ * 2. `git describe --tags --always`, for normal local builds with full git history.
+ * 3. `GITHUB_SHA` (truncated) — useful in shallow CI checkouts where git history is not available.
+ * 4. `0.0.0-SNAPSHOT` fallback.
+ *
+ * `git describe` is allowed to fail without breaking the build, because some CI
+ * environments do not have a full checkout (e.g. `fetch-depth: 1`) or any tags
+ * reachable, in which case the command exits with code 128.
+ */
+fun Project.resolveSwiftKitVersion(): String {
+    findProperty("swiftkitVersion")?.toString()?.takeIf { it.isNotBlank() }?.let { return it }
+
+    val gitVersion = runCatching {
+        providers.exec {
+            commandLine("git", "describe", "--tags", "--always")
+            workingDir = rootDir
+            isIgnoreExitValue = true
+        }.standardOutput.asText.get().trim()
+    }.getOrNull()
+    if (!gitVersion.isNullOrBlank()) return gitVersion
+
+    System.getenv("GITHUB_SHA")?.take(12)?.takeIf { it.isNotBlank() }?.let { return it }
+
+    return "0.0.0-SNAPSHOT"
+}
diff --git a/SwiftKitCore/build.gradle.kts b/SwiftKitCore/build.gradle.kts
index 89d8f5c46..fcf0590bc 100644
--- a/SwiftKitCore/build.gradle.kts
+++ b/SwiftKitCore/build.gradle.kts
@@ -12,6 +12,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+import org.swift.build.utils.resolveSwiftKitVersion
+
 plugins {
     id("build-logic.java-application-conventions")
     id("me.champeau.jmh") version "0.7.2"
@@ -19,7 +21,9 @@ plugins {
 }
 
 group = "org.swift.swiftkit"
-version = "1.0-SNAPSHOT"
+
+version = resolveSwiftKitVersion()
+
 base {
     archivesName = "swiftkit-core"
 }
@@ -34,8 +38,6 @@ publishing {
         create<MavenPublication>("maven") {
             groupId = group as? String
             artifactId = "swiftkit-core"
-            version = "1.0-SNAPSHOT"
-
             from(components["java"])
         }
     }
diff --git a/SwiftKitFFM/build.gradle.kts b/SwiftKitFFM/build.gradle.kts
index 98a988900..a56f9df1c 100644
--- a/SwiftKitFFM/build.gradle.kts
+++ b/SwiftKitFFM/build.gradle.kts
@@ -12,13 +12,16 @@
 //
 //===----------------------------------------------------------------------===//
 
+import org.swift.build.utils.resolveSwiftKitVersion
+
 plugins {
     id("build-logic.java-application-conventions")
     `maven-publish`
 }
 
 group = "org.swift.swiftkit"
-version = "1.0-SNAPSHOT"
+
+version = resolveSwiftKitVersion()
 
 base {
     archivesName = "swiftkit-ffm"
@@ -34,8 +37,6 @@ publishing {
         create<MavenPublication>("maven") {
             groupId = group as? String
             artifactId = "swiftkit-ffm"
-            version = "1.0-SNAPSHOT"
-
             from(components["java"])
         }
     }