feat(workspace): add Gradle multi-project workspace discovery

Discover subprojects in Gradle multi-project builds using a custom init
script that emits structured project listings. Supports Groovy and Kotlin
DSL variants, wrapper detection via gradlew traversal, and
workspaceDiscoveryIgnore filtering.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Strum355

src/index.js

@@ -8,6 +8,7 @@ import fs from 'node:fs'
 import { getCustom } from "./tools.js";
 import { resolveBatchMetadata, resolveContinueOnError } from './batch_opts.js'
 import {
+	discoverGradleSubprojects,
 	discoverMavenModules,
 	discoverWorkspaceCrates,
 	discoverWorkspacePackages,
@@ -24,6 +25,7 @@ export { getProjectLicense, findLicenseFilePath, identifyLicense, getLicenseDeta
 
 export default { componentAnalysis, stackAnalysis, stackAnalysisBatch, imageAnalysis, validateToken, generateSbom }
 export {
+	discoverGradleSubprojects,
 	discoverMavenModules,
 	discoverWorkspacePackages,
 	discoverWorkspaceCrates,
@@ -321,7 +323,7 @@ async function generateOneSbom(manifestPath, workspaceOpts) {
  *
  * @param {string} root - Resolved workspace root
  * @param {Options} opts
- * @returns {Promise<{ ecosystem: 'javascript' | 'cargo' | 'maven' | 'unknown', manifestPaths: string[] }>}
+ * @returns {Promise<{ ecosystem: 'javascript' | 'cargo' | 'maven' | 'gradle' | 'unknown', manifestPaths: string[] }>}
  * @private
  */
 async function detectWorkspaceManifests(root, opts) {
@@ -341,6 +343,15 @@ async function detectWorkspaceManifests(root, opts) {
 		}
 	}
 
+	const hasGradleSettings = fs.existsSync(path.join(root, 'settings.gradle'))
+		|| fs.existsSync(path.join(root, 'settings.gradle.kts'))
+	if (hasGradleSettings) {
+		const manifestPaths = await discoverGradleSubprojects(root, opts)
+		if (manifestPaths.length > 0) {
+			return { ecosystem: 'gradle', manifestPaths }
+		}
+	}
+
 	const hasJsLock = fs.existsSync(path.join(root, 'pnpm-lock.yaml'))
 		|| fs.existsSync(path.join(root, 'yarn.lock'))
 		|| fs.existsSync(path.join(root, 'package-lock.json'))

src/workspace.js

@@ -1,4 +1,5 @@
 import fs from 'node:fs'
+import os from 'node:os'
 import path from 'node:path'
 
 import fg from 'fast-glob'
@@ -12,6 +13,8 @@ const DEFAULT_WORKSPACE_DISCOVERY_IGNORE = [
 	'**/node_modules/**',
 	'**/.git/**',
 	'**/target/**',
+	'**/build/**',
+	'**/.gradle/**',
 ]
 
 /**
@@ -376,6 +379,120 @@ function parseMavenModuleList(raw) {
 	return match[1].split(',').map(s => s.trim()).filter(Boolean)
 }
 
+/** Gradle init script that emits structured project listing. */
+const GRADLE_INIT_SCRIPT = `allprojects {
+    task daListProjects {
+        doLast {
+            println "::DA_PROJECT::\${project.path}::\${project.projectDir}"
+        }
+    }
+}
+`
+
+/**
+ * Resolve the Gradle binary, respecting wrapper preference.
+ *
+ * @param {string} startDir - Directory from which to start the wrapper search
+ * @param {import('./index.js').Options} [opts={}]
+ * @returns {string} Path to the Gradle binary
+ */
+function resolveGradleBinary(startDir, opts = {}) {
+	const localWrapper = 'gradlew' + (process.platform === 'win32' ? '.bat' : '')
+	const useWrapper = getWrapperPreference('gradle', opts)
+	if (useWrapper) {
+		const wrapper = traverseForWrapper(startDir, localWrapper)
+		if (wrapper !== undefined) {
+			return wrapper
+		}
+	}
+	return getCustomPath('gradle', opts)
+}
+
+/**
+ * Discover all build.gradle[.kts] manifest paths in a Gradle multi-project build.
+ * Uses a custom init script to get structured project listing.
+ *
+ * @param {string} workspaceRoot - Absolute or relative path to workspace root (must contain settings.gradle[.kts])
+ * @param {import('./index.js').Options} [opts={}]
+ * @returns {Promise<string[]>} Paths to build.gradle[.kts] files (absolute)
+ */
+export async function discoverGradleSubprojects(workspaceRoot, opts = {}) {
+	const root = path.resolve(workspaceRoot)
+	const hasSettings = fs.existsSync(path.join(root, 'settings.gradle'))
+		|| fs.existsSync(path.join(root, 'settings.gradle.kts'))
+
+	if (!hasSettings) {
+		return []
+	}
+
+	const gradleBin = resolveGradleBinary(root, opts)
+	const manifestPaths = []
+
+	const rootBuildKts = path.join(root, 'build.gradle.kts')
+	const rootBuild = path.join(root, 'build.gradle')
+	if (fs.existsSync(rootBuildKts)) {
+		manifestPaths.push(rootBuildKts)
+	} else if (fs.existsSync(rootBuild)) {
+		manifestPaths.push(rootBuild)
+	}
+
+	const initScriptPath = path.join(os.tmpdir(), `da-list-projects-${process.pid}.gradle`)
+	try {
+		fs.writeFileSync(initScriptPath, GRADLE_INIT_SCRIPT)
+		let output
+		try {
+			output = invokeCommand(gradleBin, [
+				'-q', '--no-daemon',
+				'--init-script', initScriptPath,
+				'daListProjects',
+			], { cwd: root })
+		} catch {
+			const ignorePatterns = resolveWorkspaceDiscoveryIgnore(opts)
+			return filterManifestPathsByDiscoveryIgnore(manifestPaths, root, ignorePatterns)
+		}
+
+		const projects = parseGradleInitScriptOutput(output.toString())
+		for (const proj of projects) {
+			if (proj.path === ':') {
+				continue
+			}
+			const projDir = path.resolve(proj.dir)
+			const buildKts = path.join(projDir, 'build.gradle.kts')
+			const buildGroovy = path.join(projDir, 'build.gradle')
+			if (fs.existsSync(buildKts)) {
+				manifestPaths.push(buildKts)
+			} else if (fs.existsSync(buildGroovy)) {
+				manifestPaths.push(buildGroovy)
+			}
+		}
+	} finally {
+		try { fs.unlinkSync(initScriptPath) } catch { /* ignore */ }
+	}
+
+	const ignorePatterns = resolveWorkspaceDiscoveryIgnore(opts)
+	return filterManifestPathsByDiscoveryIgnore(manifestPaths, root, ignorePatterns)
+}
+
+/**
+ * Parse the structured output from the Gradle init script.
+ *
+ * @param {string} raw - Raw stdout from gradle
+ * @returns {{ path: string, dir: string }[]}
+ */
+function parseGradleInitScriptOutput(raw) {
+	const projects = []
+	for (const line of raw.split('\n')) {
+		if (!line.startsWith('::DA_PROJECT::')) {
+			continue
+		}
+		const parts = line.split('::').filter(Boolean)
+		if (parts.length >= 3) {
+			projects.push({ path: parts[1], dir: parts[2] })
+		}
+	}
+	return projects
+}
+
 /**
  * Discover all Cargo.toml manifest paths in a Cargo workspace.
  * Uses `cargo metadata` to get workspace members.

test/providers/tst_manifests/gradle/gradle_mixed_variants/app/build.gradle

@@ -0,0 +1 @@
+// app build groovy

test/providers/tst_manifests/gradle/gradle_mixed_variants/build.gradle.kts

@@ -0,0 +1 @@
+// root build kts

test/providers/tst_manifests/gradle/gradle_mixed_variants/lib/build.gradle.kts

@@ -0,0 +1 @@
+// lib build kts

test/providers/tst_manifests/gradle/gradle_mixed_variants/settings.gradle.kts

@@ -0,0 +1 @@
+include ':app', ':lib'

test/providers/tst_manifests/gradle/gradle_multi_project/app/build.gradle

@@ -0,0 +1 @@
+// app build

test/providers/tst_manifests/gradle/gradle_multi_project/build.gradle

@@ -0,0 +1 @@
+// root build

test/providers/tst_manifests/gradle/gradle_multi_project/lib/build.gradle

@@ -0,0 +1 @@
+// lib build

test/providers/tst_manifests/gradle/gradle_multi_project/settings.gradle

@@ -0,0 +1 @@
+include ':app', ':lib'