launcher 2.6.2: properly detect MPS 2025.1 vs 2025.2

Author: sergej-koscejev

launcher/CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres
 to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 2.6.2
+
+### Fixed
+
+- MPS 2025.1 vs 2025.2 detection logic should now work properly.
+
 ## 2.6.1
 
 ### Fixed

launcher/gradle.properties

@@ -1 +1 @@
-version.launcher=2.6.1
+version.launcher=2.6.2

launcher/src/main/java/de/itemis/mps/gradle/launcher/MpsVersionDetection.java

@@ -34,17 +34,34 @@ public static Provider<String> fromMpsHome(ProjectLayout layout, ProviderFactory
                 throw new GradleException("Could not read mps.build.number property from file " + buildPropertiesFile.getAsFile());
             }
 
-            return buildNumberToVersion(buildNumber);
+            String buildNumberWithoutPrefix = buildNumber.replaceFirst("^\\p{Alpha}+-", "");
+            return buildNumberToVersion(buildNumberWithoutPrefix);
         });
     }
 
     private static String buildNumberToVersion(String buildNumber) {
-        String buildNumberWithoutPrefix = buildNumber.replaceFirst("^\\p{Alpha}+-", "");
-        if (buildNumberWithoutPrefix.compareTo("251.23774.10000") >= 0 && buildNumberWithoutPrefix.compareTo("252") < 0) {
-            // 251.23774.10000 and above are pre-releases of 2025.2
-            return "2025.2";
+        if (!Character.isDigit(buildNumber.charAt(0))) {
+            throw new IllegalArgumentException("build number must start with a digit");
         }
 
-        return buildNumberWithoutPrefix.replaceFirst("^(\\d{2})(\\d)\\..*", "20$1.$2");
+        if (buildNumber.startsWith("251.23774.")) {
+            // 251.23774.10000 and above are actually pre-releases of 2025.2
+            String suffix = buildNumber.substring("251.23774.".length());
+            int suffixAsInt;
+            try {
+                suffixAsInt = Integer.parseInt(suffix);
+            } catch (NumberFormatException nfe) {
+                // Something unknown in the number, treat it as 2025.1
+                return "2025.1";
+            }
+
+            if (suffixAsInt >= 10000) {
+                return "2025.2";
+            } else {
+                return "2025.1";
+            }
+        }
+
+        return buildNumber.replaceFirst("^(\\d{2})(\\d)\\..*", "20$1.$2");
     }
 }

launcher/src/test/java/de/itemis/mps/gradle/launcher/MpsVersionDetectionTest.java

@@ -28,6 +28,20 @@ public void readsVersionFromBuildProperties(@TempDir File tempDir) throws IOExce
                 project.provider(() -> mpsDir)).get());
     }
 
+    @Test
+    public void version251(@TempDir File tempDir) throws IOException {
+        final Project project = ProjectBuilder.builder().withProjectDir(tempDir).build();
+
+        File mpsDir = new File(tempDir, "build/mps");
+        File buildProperties = new File(mpsDir, "build.properties");
+
+        FileUtils.writeStringToFile(buildProperties, "mps.build.number=MPS-251.23774.541\n",
+                StandardCharsets.ISO_8859_1);
+
+        assertEquals("2025.1", MpsVersionDetection.fromMpsHome(project.getLayout(), project.getProviders(),
+                project.provider(() -> mpsDir)).get());
+    }
+
     @Test
     public void prereleaseOf252(@TempDir File tempDir) throws IOException {
         final Project project = ProjectBuilder.builder().withProjectDir(tempDir).build();