Make os.home a def

build.sc

@@ -126,6 +126,7 @@ object os extends Module {
   object jvm extends Cross[OsJvmModule](scalaVersions)
   trait OsJvmModule extends OsModule with MiMaChecks {
     object test extends ScalaTests with OsLibTestModule
+    object nohometest extends ScalaTests with OsLibTestModule
   }
 
   object native extends Cross[OsNativeModule](scalaVersions)
@@ -134,6 +135,7 @@ object os extends Module {
     object test extends ScalaNativeTests with OsLibTestModule {
       def nativeLinkStubs = true
     }
+    object nohometest extends ScalaNativeTests with OsLibTestModule
   }
 
   object watch extends Module {

os/nohometest/src/NoHomeTests.scala

@@ -0,0 +1,25 @@
+package test.os
+
+import utest._
+
+object NoHomeTests extends TestSuite {
+  private lazy val isWindows = sys.props("os.name").toLowerCase().contains("windows")
+
+  val tests = Tests {
+    test("pwd when home is not available") {
+      System.setProperty("user.home", "?")
+      val homeException = intercept[IllegalArgumentException] { os.home }
+        .getMessage()
+
+      val expectedException =
+        if (isWindows)
+          "Illegal char <?> at index 0: ?"
+        else
+          "requirement failed: ? is not an absolute path"
+
+      assert(homeException == expectedException)
+      os.pwd
+      ()
+    }
+  }
+}

os/src-jvm/package.scala

@@ -23,10 +23,17 @@ package object os {
     os.ResourcePath.resource(resRoot)
   }
 
+  // See https://github.com/com-lihaoyi/os-lib/pull/239
+  // and https://github.com/lightbend/mima/issues/794
+  // why the need the inner object to preserve binary compatibility
+  private object _home {
+    lazy val value = Path(System.getProperty("user.home"))
+  }
+
   /**
    * The user's home directory
    */
-  val home: Path = Path(System.getProperty("user.home"))
+  def home: Path = _home.value
 
   /**
    * The current working directory for this process.

os/src-native/package.scala

@@ -16,10 +16,17 @@ package object os {
     path
   }
 
+  // See https://github.com/com-lihaoyi/os-lib/pull/239
+  // and https://github.com/lightbend/mima/issues/794
+  // why the need the inner object to preserve binary compatibility
+  private object _home {
+    lazy val value = Path(System.getProperty("user.home"))
+  }
+
   /**
    * The user's home directory
    */
-  val home: Path = Path(System.getProperty("user.home"))
+  def home: Path = _home.value
 
   /**
    * The current working directory for this process.