From 4b8a4e2bdade7fc09247a251abc17fbb1470d270 Mon Sep 17 00:00:00 2001
From: Jiaxiang Chen <jiaxiang@google.com>
Date: Tue, 11 Oct 2022 00:09:35 -0700
Subject: [PATCH] use try catch clause for more accurate relative path check.

---
 .../ksp/processing/impl/CodeGeneratorImpl.kt  |  6 +++--
 .../com/google/devtools/ksp/Incremental.kt    |  9 +++++---
 .../google/devtools/ksp/test/PlaygroundIT.kt  | 22 +++++++++++++++++++
 3 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/common-util/src/main/kotlin/com/google/devtools/ksp/processing/impl/CodeGeneratorImpl.kt b/common-util/src/main/kotlin/com/google/devtools/ksp/processing/impl/CodeGeneratorImpl.kt
index ed017edb10..f840b8c208 100644
--- a/common-util/src/main/kotlin/com/google/devtools/ksp/processing/impl/CodeGeneratorImpl.kt
+++ b/common-util/src/main/kotlin/com/google/devtools/ksp/processing/impl/CodeGeneratorImpl.kt
@@ -156,11 +156,13 @@ class CodeGeneratorImpl(
     }
 
     private val File.relativeFile: File
-        get() =
-            if (this.startsWith(buildDir))
+        get() {
+            val buildDirPrefix = if (buildDir.path.startsWith("/")) buildDir.path else buildDir.path.replace("\\", "/")
+            return if (this.startsWith(buildDirPrefix))
                 relativeTo(buildDir)
             else
                 relativeTo(projectBase)
+        }
 
     private fun associate(sources: List<KSFile>, outputPath: File) {
         if (!isIncremental)
diff --git a/compiler-plugin/src/main/kotlin/com/google/devtools/ksp/Incremental.kt b/compiler-plugin/src/main/kotlin/com/google/devtools/ksp/Incremental.kt
index 2de08ff2e4..d3990914a1 100644
--- a/compiler-plugin/src/main/kotlin/com/google/devtools/ksp/Incremental.kt
+++ b/compiler-plugin/src/main/kotlin/com/google/devtools/ksp/Incremental.kt
@@ -230,11 +230,14 @@ class IncrementalContext(
 
     // Ugly, but better than copying the private logics out of stdlib.
     // TODO: get rid of `relativeTo` if possible.
-    private fun String.toRelativeFile(): File =
-        if (this.startsWith(buildDir.path))
+    private fun String.toRelativeFile(): File {
+        val buildDirPrefix = if (buildDir.path.startsWith("/")) buildDir.path else buildDir.path.replace("\\", "/")
+        return if (this.startsWith(buildDirPrefix)) {
             File(this).relativeTo(buildDir)
-        else
+        } else {
             File(this).relativeTo(baseDir)
+        }
+    }
 
     private val KSFile.relativeFile
         get() = filePath.toRelativeFile()
diff --git a/integration-tests/src/test/kotlin/com/google/devtools/ksp/test/PlaygroundIT.kt b/integration-tests/src/test/kotlin/com/google/devtools/ksp/test/PlaygroundIT.kt
index 2e16375603..73640fa1e5 100644
--- a/integration-tests/src/test/kotlin/com/google/devtools/ksp/test/PlaygroundIT.kt
+++ b/integration-tests/src/test/kotlin/com/google/devtools/ksp/test/PlaygroundIT.kt
@@ -65,6 +65,28 @@ class PlaygroundIT {
         project.restore("workload/build.gradle.kts")
     }
 
+    @Test
+    fun testArbitraryBuildDir() {
+        Assume.assumeTrue(System.getProperty("os.name").startsWith("Windows", ignoreCase = true))
+        val gradleRunner = GradleRunner.create().withProjectDir(project.root)
+
+        File(project.root, "workload/build.gradle.kts")
+            .appendText("project.buildDir = File(\"D:/build/\")")
+        val result = gradleRunner.withArguments("build").build()
+
+        Assert.assertEquals(TaskOutcome.SUCCESS, result.task(":workload:build")?.outcome)
+
+        val artifact = File("D:/build/libs/workload-1.0-SNAPSHOT.jar")
+        Assert.assertTrue(artifact.exists())
+
+        JarFile(artifact).use { jarFile ->
+            Assert.assertTrue(jarFile.getEntry("TestProcessor.log").size > 0)
+            Assert.assertTrue(jarFile.getEntry("hello/HELLO.class").size > 0)
+            Assert.assertTrue(jarFile.getEntry("g/G.class").size > 0)
+            Assert.assertTrue(jarFile.getEntry("com/example/AClassBuilder.class").size > 0)
+        }
+    }
+
     @Test
     fun testAllowSourcesFromOtherPlugins() {
         fun checkGBuilder() {