Propagate `gradle.properties` to `buildSrc`

Update `buildSrc` so that properties frok the root `gradle.properties`
file are available.

See gh-42333

buildSrc/build.gradle

@@ -13,18 +13,7 @@ repositories {
 sourceCompatibility = 17
 targetCompatibility = 17
 
-def versions = [:]
-new File(projectDir.parentFile, "gradle.properties").withInputStream {
-	def properties = new Properties()
-	properties.load(it)
-	["assertj", "commonsCodec", "hamcrest", "jackson", "junitJupiter",
-		"kotlin", "maven"].each {
-		versions[it] = properties[it + "Version"]
-	}
-}
-versions["springFramework"] = "6.0.12"
-ext.set("versions", versions)
-if (versions.springFramework.contains("-")) {
+if ("${springFrameworkVersion}".contains("-")) {
 	repositories {
 		maven { url "https://repo.spring.io/milestone" }
 		maven { url "https://repo.spring.io/snapshot" }
@@ -32,32 +21,32 @@ if (versions.springFramework.contains("-")) {
 }
 
 checkstyle {
-	toolVersion = "10.12.4"
+	toolVersion = "{checkstyleToolVersion}"
 }
 
 dependencies {
 	checkstyle("com.puppycrawl.tools:checkstyle:${checkstyle.toolVersion}")
 	checkstyle("io.spring.javaformat:spring-javaformat-checkstyle:${javaFormatVersion}")
 
-	implementation(platform("org.springframework:spring-framework-bom:${versions.springFramework}"))
-	implementation("com.fasterxml.jackson.core:jackson-databind:${versions.jackson}")
+	implementation(platform("org.springframework:spring-framework-bom:${springFrameworkVersion}"))
+	implementation("com.fasterxml.jackson.core:jackson-databind:${jacksonVersion}")
 	implementation("com.gradle:develocity-gradle-plugin:3.17.2")
 	implementation("com.tngtech.archunit:archunit:1.3.0")
-	implementation("commons-codec:commons-codec:${versions.commonsCodec}")
+	implementation("commons-codec:commons-codec:${commonsCodecVersion}")
 	implementation("de.undercouch.download:de.undercouch.download.gradle.plugin:5.5.0")
 	implementation("io.spring.javaformat:spring-javaformat-gradle-plugin:${javaFormatVersion}")
-	implementation("org.apache.maven:maven-embedder:${versions.maven}")
+	implementation("org.apache.maven:maven-embedder:${mavenVersion}")
 	implementation("org.asciidoctor:asciidoctor-gradle-jvm:4.0.2")
-	implementation("org.jetbrains.kotlin:kotlin-gradle-plugin:${versions.kotlin}")
-	implementation("org.jetbrains.kotlin:kotlin-compiler-embeddable:${versions.kotlin}")
+	implementation("org.jetbrains.kotlin:kotlin-gradle-plugin:${kotlinVersion}")
+	implementation("org.jetbrains.kotlin:kotlin-compiler-embeddable:${kotlinVersion}")
 	implementation("org.springframework:spring-context")
 	implementation("org.springframework:spring-core")
 	implementation("org.springframework:spring-web")
 	implementation("io.spring.nohttp:nohttp-gradle:0.0.11")
 
-	testImplementation("org.assertj:assertj-core:${versions.assertj}")
-	testImplementation("org.hamcrest:hamcrest:${versions.hamcrest}")
-	testImplementation("org.junit.jupiter:junit-jupiter:${versions.junitJupiter}")
+	testImplementation("org.assertj:assertj-core:${assertjVersion}")
+	testImplementation("org.hamcrest:hamcrest:${hamcrestVersion}")
+	testImplementation("org.junit.jupiter:junit-jupiter:${junitJupiterVersion}")
 	testImplementation("org.springframework:spring-test")
 
 	testRuntimeOnly("org.junit.platform:junit-platform-launcher")

buildSrc/gradle.properties

@@ -1 +0,0 @@
-javaFormatVersion=0.0.43

buildSrc/settings.gradle

@@ -4,3 +4,11 @@ pluginManagement {
 		gradlePluginPortal()
 	}
 }
+
+gradle.rootProject((project) -> {
+	new File(rootDir.parentFile, "gradle.properties").withInputStream {
+		def properties = new Properties()
+		properties.load(it)
+		properties.forEach(project.ext::set)
+	}
+});

gradle.properties

@@ -6,10 +6,12 @@ org.gradle.parallel=true
 org.gradle.jvmargs=-Xmx2g -Dfile.encoding=UTF-8
 
 assertjVersion=3.24.2
+checkstyleToolVersion=10.12.4
 commonsCodecVersion=1.16.1
 commonsCompressVersion=1.21
 hamcrestVersion=2.2
 jacksonVersion=2.15.4
+javaFormatVersion=0.0.43
 junitJupiterVersion=5.10.3
 kotlinVersion=1.9.25
 mavenVersion=3.9.4