Fix included-build outputs missing from save bundles

Kong's type:"path" resolved --included-build values to absolute paths,
causing ConventionBuildDirs to construct invalid doubled paths that
silently matched nothing. Drop type:"path", validate paths upfront, and
bake an included build into the default integration fixture.

Author: joshfriend

cmd/gradle-cache/integration_test.go

@@ -150,6 +150,7 @@ func TestIntegrationGradleBuildCycle(t *testing.T) {
 		"--cache-key", ctx.cacheKey,
 		"--commit", commitSHA,
 		"--gradle-user-home", ctx.gradleUserHome,
+		"--included-build", "build-logic",
 	)
 	runCLI(t, binaryPath, ctx, saveArgs...)
 
@@ -164,6 +165,7 @@ func TestIntegrationGradleBuildCycle(t *testing.T) {
 		"--ref", commitSHA,
 		"--git-dir", ctx.projectDir,
 		"--gradle-user-home", ctx.gradleUserHome,
+		"--included-build", "build-logic",
 	)
 	runCLI(t, binaryPath, ctx, restoreArgs...)
 
@@ -367,6 +369,14 @@ func verifyRestore(t *testing.T, ctx integrationCtx) {
 		t.Fatalf("expected wrapper dir after restore: %v", err)
 	}
 
+	// Included-build outputs should survive the round-trip.
+	buildLogicBuildDir := filepath.Join(ctx.projectDir, "build-logic", "build")
+	if _, err := os.Stat(buildLogicBuildDir); err != nil {
+		t.Error("build-logic/build/ was NOT restored")
+	} else {
+		t.Log("  build-logic/build/ restored")
+	}
+
 	ccRestored := filepath.Join(ctx.projectDir, ".gradle", "configuration-cache")
 	if _, err := os.Stat(ccRestored); err != nil {
 		t.Log("  configuration-cache dir was NOT restored")
@@ -525,6 +535,7 @@ dependencies { implementation("com.google.guava:guava:33.4.0-jre") }
 				"--cache-key", ctx.cacheKey,
 				"--commit", commitSHA,
 				"--gradle-user-home", ctx.gradleUserHome,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, saveArgs...)
 
@@ -537,6 +548,7 @@ dependencies { implementation("com.google.guava:guava:33.4.0-jre") }
 				"--ref", commitSHA,
 				"--git-dir", ctx.projectDir,
 				"--gradle-user-home", ctx.gradleUserHome,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, restoreArgs...)
 
@@ -574,6 +586,7 @@ dependencies { implementation("com.google.guava:guava:33.4.0-jre") }
 				"--branch", "test-branch",
 				"--gradle-user-home", ctx.gradleUserHome,
 				"--project-dir", ctx.projectDir,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, saveDeltaArgs...)
 
@@ -590,6 +603,7 @@ dependencies { implementation("com.google.guava:guava:33.4.0-jre") }
 				"--branch", "test-branch",
 				"--gradle-user-home", freshHome,
 				"--project-dir", ctx.projectDir,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, freshRestoreDelta...)
 
@@ -618,6 +632,7 @@ dependencies { implementation("com.google.guava:guava:33.4.0-jre") }
 				"--branch", "test-branch",
 				"--gradle-user-home", ctx.gradleUserHome,
 				"--project-dir", ctx.projectDir,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, fullRestoreDelta...)
 
@@ -832,22 +847,42 @@ func TestIntegrationDeltaConfigurationCache(t *testing.T) {
 	}
 
 	for _, tt := range []struct {
-		name      string
-		fixture   string
-		buildFile string
-		change    string // appended to build file to invalidate CC
+		name    string
+		fixture string
+		mutate  func(t *testing.T, projectDir string) // invalidate CC
 	}{
 		{
-			name:      "groovy-dsl",
-			fixture:   "groovy-project",
-			buildFile: "build.gradle",
-			change:    "\n// force CC invalidation\n",
+			name:    "groovy-dsl",
+			fixture: "groovy-project",
+			mutate: func(t *testing.T, projectDir string) {
+				appendToFile(t, filepath.Join(projectDir, "build.gradle"), "\n// force CC invalidation\n")
+			},
 		},
 		{
-			name:      "kotlin-dsl",
-			fixture:   "gradle-project",
-			buildFile: "build.gradle.kts",
-			change:    "\n// force CC invalidation\n",
+			name:    "kotlin-dsl",
+			fixture: "gradle-project",
+			mutate: func(t *testing.T, projectDir string) {
+				appendToFile(t, filepath.Join(projectDir, "build.gradle.kts"), "\n// force CC invalidation\n")
+			},
+		},
+		{
+			name:    "included-build-plugin-change",
+			fixture: "gradle-project",
+			mutate: func(t *testing.T, projectDir string) {
+				must(t, os.WriteFile(
+					filepath.Join(projectDir, "build-logic", "src", "main", "java", "com", "example", "IncludedPlugin.java"),
+					[]byte(`package com.example;
+
+import org.gradle.api.Plugin;
+import org.gradle.api.Project;
+
+public class IncludedPlugin implements Plugin<Project> {
+    @Override public void apply(Project project) {
+        project.getLogger().lifecycle("IncludedPlugin applied (modified)");
+    }
+}
+`), 0o644))
+			},
 		},
 	} {
 		tt := tt
@@ -867,6 +902,7 @@ func TestIntegrationDeltaConfigurationCache(t *testing.T) {
 				"--cache-key", ctx.cacheKey,
 				"--commit", commitSHA,
 				"--gradle-user-home", ctx.gradleUserHome,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, saveArgs...)
 
@@ -880,16 +916,12 @@ func TestIntegrationDeltaConfigurationCache(t *testing.T) {
 				"--ref", commitSHA,
 				"--git-dir", ctx.projectDir,
 				"--gradle-user-home", ctx.gradleUserHome,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, restoreArgs...)
 
-			// Modify build file to invalidate configuration cache.
-			buildFilePath := filepath.Join(ctx.projectDir, tt.buildFile)
-			f, err := os.OpenFile(buildFilePath, os.O_APPEND|os.O_WRONLY, 0o644)
-			must(t, err)
-			_, err = f.WriteString(tt.change)
-			must(t, err)
-			must(t, f.Close())
+			// Mutate the project to invalidate configuration cache.
+			tt.mutate(t, ctx.projectDir)
 
 			output := gradleRun(t, ctx.projectDir, ctx.gradlew, ctx.gradleUserHome, "build")
 			if !strings.Contains(output, "Calculating task graph") &&
@@ -905,6 +937,7 @@ func TestIntegrationDeltaConfigurationCache(t *testing.T) {
 				"--branch", "cc-test-branch",
 				"--gradle-user-home", ctx.gradleUserHome,
 				"--project-dir", ctx.projectDir,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, saveDeltaArgs...)
 
@@ -919,6 +952,7 @@ func TestIntegrationDeltaConfigurationCache(t *testing.T) {
 				"--branch", "cc-test-branch",
 				"--gradle-user-home", ctx.gradleUserHome,
 				"--project-dir", ctx.projectDir,
+				"--included-build", "build-logic",
 			)
 			runCLI(t, binaryPath, ctx, restoreDeltaArgs...)
 
@@ -928,7 +962,7 @@ func TestIntegrationDeltaConfigurationCache(t *testing.T) {
 				t.Fatalf("configuration-cache dir not restored: %v", err)
 			}
 
-			// ── Step 5: Verify CC hit with the modified build file ──────
+			// ── Step 5: Verify CC hit after delta restore ──────────────
 			t.Log("Step 5: Verifying configuration cache hit...")
 			output = gradleRun(t, ctx.projectDir, ctx.gradlew, ctx.gradleUserHome, "build")
 
@@ -945,6 +979,15 @@ func TestIntegrationDeltaConfigurationCache(t *testing.T) {
 	}
 }
 
+func appendToFile(t *testing.T, path, content string) {
+	t.Helper()
+	f, err := os.OpenFile(path, os.O_APPEND|os.O_WRONLY, 0o644)
+	must(t, err)
+	_, err = f.WriteString(content)
+	must(t, err)
+	must(t, f.Close())
+}
+
 func extractLine(output, substr string) string {
 	for _, line := range strings.Split(output, "\n") {
 		if strings.Contains(strings.ToLower(line), strings.ToLower(substr)) {

cmd/gradle-cache/main.go

@@ -4,10 +4,12 @@ package main
 
 import (
 	"context"
+	"fmt"
 	"log/slog"
 	"os"
 	"runtime"
 	"runtime/pprof"
+	"strings"
 
 	"github.com/alecthomas/errors"
 	"github.com/alecthomas/kong"
@@ -61,6 +63,26 @@ func (f *backendFlags) validate() error {
 	return nil
 }
 
+// validateIncludedBuilds checks that each --included-build value refers to an
+// existing directory (or, for glob patterns like "build-logic/*", that the
+// parent directory exists).
+func validateIncludedBuilds(entries []string) error {
+	for _, entry := range entries {
+		dir := entry
+		if strings.HasSuffix(dir, "/*") {
+			dir = strings.TrimSuffix(dir, "/*")
+		}
+		info, err := os.Stat(dir)
+		if err != nil {
+			return fmt.Errorf("--included-build %q: %w", entry, err)
+		}
+		if !info.IsDir() {
+			return fmt.Errorf("--included-build %q: not a directory", entry)
+		}
+	}
+	return nil
+}
+
 // ── Restore ─────────────────────────────────────────────────────────────────
 
 type RestoreCmd struct {
@@ -71,11 +93,16 @@ type RestoreCmd struct {
 	Commit         string   `help:"Specific commit SHA to try directly, skipping history walk."`
 	MaxBlocks      int      `help:"Number of distinct-author commit blocks to search." default:"20"`
 	GradleUserHome string   `help:"Path to GRADLE_USER_HOME." env:"GRADLE_USER_HOME" type:"path"`
-	IncludedBuilds []string `help:"Included build directories whose build/ output to restore. May be repeated." name:"included-build" type:"path"`
+	IncludedBuilds []string `help:"Included build directories whose build/ output to restore. May be repeated." name:"included-build"`
 	Branch         string   `help:"Branch name to also apply a delta bundle for." optional:""`
 }
 
-func (c *RestoreCmd) AfterApply() error { return c.validate() }
+func (c *RestoreCmd) AfterApply() error {
+	if err := c.validate(); err != nil {
+		return err
+	}
+	return validateIncludedBuilds(c.IncludedBuilds)
+}
 
 func (c *RestoreCmd) Run(ctx context.Context, metrics gradlecache.MetricsClient) error {
 	slog.Debug(gradleUserHomeEnv, "path", c.GradleUserHome)
@@ -104,10 +131,15 @@ type RestoreDeltaCmd struct {
 	Branch         string   `help:"Branch name to look up a delta for." required:""`
 	GradleUserHome string   `help:"Path to GRADLE_USER_HOME." env:"GRADLE_USER_HOME" type:"path"`
 	ProjectDir     string   `help:"Project directory for routing project-specific cache entries." type:"path"`
-	IncludedBuilds []string `help:"Included build directories whose build/ output to route. May be repeated." name:"included-build" type:"path"`
+	IncludedBuilds []string `help:"Included build directories whose build/ output to route. May be repeated." name:"included-build"`
 }
 
-func (c *RestoreDeltaCmd) AfterApply() error { return c.validate() }
+func (c *RestoreDeltaCmd) AfterApply() error {
+	if err := c.validate(); err != nil {
+		return err
+	}
+	return validateIncludedBuilds(c.IncludedBuilds)
+}
 
 func (c *RestoreDeltaCmd) Run(ctx context.Context, metrics gradlecache.MetricsClient) error {
 	slog.Debug(gradleUserHomeEnv, "path", c.GradleUserHome)
@@ -133,10 +165,15 @@ type SaveCmd struct {
 	Commit         string   `help:"Commit SHA to tag this bundle with. Defaults to HEAD of --git-dir."`
 	GitDir         string   `help:"Path to the git repository." default:"." type:"path" hidden:""`
 	GradleUserHome string   `help:"Path to GRADLE_USER_HOME." env:"GRADLE_USER_HOME" type:"path"`
-	IncludedBuilds []string `help:"Included build directories whose build/ output to archive. May be repeated." name:"included-build" type:"path"`
+	IncludedBuilds []string `help:"Included build directories whose build/ output to archive. May be repeated." name:"included-build"`
 }
 
-func (c *SaveCmd) AfterApply() error { return c.validate() }
+func (c *SaveCmd) AfterApply() error {
+	if err := c.validate(); err != nil {
+		return err
+	}
+	return validateIncludedBuilds(c.IncludedBuilds)
+}
 
 func (c *SaveCmd) Run(ctx context.Context, metrics gradlecache.MetricsClient) error {
 	slog.Debug(gradleUserHomeEnv, "path", c.GradleUserHome)
@@ -162,10 +199,15 @@ type SaveDeltaCmd struct {
 	Branch         string   `help:"Branch name to save the delta under." required:""`
 	GradleUserHome string   `help:"Path to GRADLE_USER_HOME." env:"GRADLE_USER_HOME" type:"path"`
 	ProjectDir     string   `help:"Project directory to scan for project-specific cache changes." type:"path"`
-	IncludedBuilds []string `help:"Included build directories whose build/ output to include in delta. May be repeated." name:"included-build" type:"path"`
+	IncludedBuilds []string `help:"Included build directories whose build/ output to include in delta. May be repeated." name:"included-build"`
 }
 
-func (c *SaveDeltaCmd) AfterApply() error { return c.validate() }
+func (c *SaveDeltaCmd) AfterApply() error {
+	if err := c.validate(); err != nil {
+		return err
+	}
+	return validateIncludedBuilds(c.IncludedBuilds)
+}
 
 func (c *SaveDeltaCmd) Run(ctx context.Context, metrics gradlecache.MetricsClient) error {
 	slog.Debug(gradleUserHomeEnv, "path", c.GradleUserHome)

cmd/gradle-cache/testdata/gradle-project/build-logic/build.gradle.kts

@@ -0,0 +1,12 @@
+plugins {
+    `java-gradle-plugin`
+}
+
+gradlePlugin {
+    plugins {
+        create("included") {
+            id = "com.example.included"
+            implementationClass = "com.example.IncludedPlugin"
+        }
+    }
+}

cmd/gradle-cache/testdata/gradle-project/build-logic/settings.gradle.kts

@@ -0,0 +1 @@
+rootProject.name = "build-logic"

cmd/gradle-cache/testdata/gradle-project/build-logic/src/main/java/com/example/IncludedPlugin.java

@@ -0,0 +1,11 @@
+package com.example;
+
+import org.gradle.api.Plugin;
+import org.gradle.api.Project;
+
+public class IncludedPlugin implements Plugin<Project> {
+    @Override
+    public void apply(Project project) {
+        // no-op plugin — exercises the included-build path
+    }
+}

cmd/gradle-cache/testdata/gradle-project/build.gradle.kts

@@ -1,5 +1,6 @@
 plugins {
     kotlin("jvm") version "2.3.20"
+    id("com.example.included")
 }
 
 repositories {

cmd/gradle-cache/testdata/gradle-project/settings.gradle.kts

@@ -1 +1,5 @@
+pluginManagement {
+    includeBuild("build-logic")
+}
+
 rootProject.name = "cache-test"

cmd/gradle-cache/testdata/groovy-project/build.gradle

@@ -1,5 +1,6 @@
 plugins {
     id 'java'
+    id 'com.example.included'
 }
 
 repositories {

cmd/gradle-cache/testdata/groovy-project/settings.gradle

@@ -1 +1,5 @@
+pluginManagement {
+    includeBuild('build-logic')
+}
+
 rootProject.name = 'groovy-cache-test'