spring-test-slices: Spring Boot 4.1.2 test slices lab (@WebMvcTest, @JsonTest, @RestClientTest, @DataJpaTest vs @SpringBootTest)

Co-Authored-By: Claude Sonnet 5.5 <[email protected]> Claude-Session: https://claude.ai/code/session_017ic4b7Jbw5CxUQ13D7gn25
2026-11-14 15:26:55 +05:30
parent c92977b23d
commit d7497c8ab1
53 changed files with 1547 additions and 0 deletions
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+#!/usr/bin/env bash
+# Regenerates every file in spring-test-slices/output/.
+# Needs JDK 25 and Maven on the PATH. Takes about a minute.
+set -euo pipefail
+cd "$(dirname "$0")/.."
+
+OUT=output
+# keep transcripts free of JVM launcher noise that varies per machine
+filter() { grep -vE '^(Picked up JAVA_TOOL_OPTIONS|WARNING: )' || true; }
+
+rm -f "$OUT"/*.txt
+mkdir -p "$OUT"
+
+# 1. the whole suite: every test writes its own transcript to output/ and asserts the same facts
+mvn -B -q clean test 2>&1 | filter | grep -E 'Tests run:|BUILD|ERROR' || true
+
+# 2. which test jars does spring-boot-starter-test alone bring in?
+./scripts/starter-test-only.sh
+
+# 3. startup time of each context, one test class per JVM so nothing is cached.
+#    Spring Boot logs "Started <TestClass> in N seconds" for every context it builds.
+#    Timings vary by machine and by run: read them as indicative, not as a result.
+{
+  echo "Context startup time per test class (one class per mvn run; indicative, varies between runs)"
+  echo
+  for cls in JsonSliceTest RestClientSliceTest WebMvcSliceTest DataJpaSliceTest FullContextTest; do
+    mvn -B test -Dtest="$cls" 2>&1 | grep -oE "Started $cls in [0-9.]+ seconds" | head -1
+  done
+} > "$OUT/30-startup-times.txt"
+
+echo "done: $(ls "$OUT" | wc -l) files in $OUT/"
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+#!/usr/bin/env bash
+# Which Boot test jars does spring-boot-starter-test alone bring in?
+# Resolves a throwaway project with the three production starters and ONLY spring-boot-starter-test,
+# then lists every spring-boot jar with "test" in its name. Writes output/12-starter-test-only-jars.txt.
+set -euo pipefail
+cd "$(dirname "$0")/.."
+BOOT="$(sed -n '/<artifactId>spring-boot-starter-parent<\/artifactId>/{n;s/.*<version>\(.*\)<\/version>.*/\1/p}' pom.xml)"
+TMP=target/starter-test-only
+rm -rf "$TMP" && mkdir -p "$TMP"
+cat > "$TMP/pom.xml" <<POM
+<project xmlns="http://maven.apache.org/POM/4.0.0"><modelVersion>4.0.0</modelVersion>
+  <parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>${BOOT}</version><relativePath/></parent>
+  <groupId>probe</groupId><artifactId>starter-test-only</artifactId><version>1</version>
+  <dependencies>
+    <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-webmvc</artifactId></dependency>
+    <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-jpa</artifactId></dependency>
+    <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-restclient</artifactId></dependency>
+    <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency>
+  </dependencies>
+</project>
+POM
+mvn -B -q -f "$TMP/pom.xml" dependency:build-classpath -Dmdep.outputFile=cp.txt > /dev/null 2>&1
+{
+  echo "Spring Boot ${BOOT}: webmvc + data-jpa + restclient starters, and only spring-boot-starter-test for tests"
+  echo "spring-boot jars with 'test' in the name on that classpath:"
+  tr ':' '\n' < "$TMP/cp.txt" | sed 's#.*/##' | grep -E '^spring-boot.*test' | sed 's/^/  /'
+} > output/12-starter-test-only-jars.txt