Add boot42-rc1-checklist module: Spring Boot 4.2.0-RC1 upgrade checklist run against RC1 and 4.1.2

boot42-rc1-checklist/scripts/compile-broken.sh

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+# Compiles src/broken/UsesRestTemplate.java with -Xlint:deprecation against the module classpath
+# of the given pom (default pom.xml = 4.2.0-RC1; pass pom-41.xml for the 4.1.2 baseline) and
+# stores the compiler's own message in output/05-resttemplate-compiler-warnings[-on-4.1.2].txt.
+set -u
+cd "$(dirname "$0")/.."
+POM="${1:-pom.xml}"
+LABEL=$(grep -m1 '<boot.label>' "$POM" | sed -E 's/.*<boot.label>(.*)<\/boot.label>.*/\1/')
+SUFFIX=""; [[ "$LABEL" == 4.2* ]] || SUFFIX="-on-$LABEL"
+OUT="output/05-resttemplate-compiler-warnings$SUFFIX.txt"
+mvn -B -q -f "$POM" dependency:build-classpath -Dmdep.outputFile=target/cp.txt >/dev/null 2>&1
+rm -rf target/broken && mkdir -p target/broken
+{
+  echo "# 05-resttemplate-compiler-warnings  (Spring Boot $LABEL, JDK $(javac -version 2>&1 | grep -v Picked | awk '{print $2}'))"
+  echo '$ javac -Xlint:deprecation -cp <module classpath> -d target/broken src/broken/UsesRestTemplate.java'
+  javac -Xlint:deprecation -cp "$(cat target/cp.txt)" -d target/broken src/broken/UsesRestTemplate.java 2>&1 \
+    | grep -v '^Picked up' | sed -e "s#^$(pwd)/##"
+  echo "exit: ${PIPESTATUS[0]}"
+} > "$OUT"
+cat "$OUT"