Fixed reading of .mill-jvm-opts file

build.sc

@@ -1016,9 +1016,7 @@ def launcherScript(
          |  if [ -f "$$mill_jvm_opts_file" ] ; then
          |    while IFS= read line
          |    do
-         |      case $$line in
-         |        "-X"*) mill_jvm_opts="$${mill_jvm_opts} $$line"
-         |      esac
+         |      mill_jvm_opts="$${mill_jvm_opts} $$(echo $$line | grep -v "^[[:space:]]*[#]")"
          |    done <"$$mill_jvm_opts_file"
          |    mill_jvm_opts="$${mill_jvm_opts} -Dmill.jvm_opts_applied=true"
          |  fi

integration/forked-server/src/forked-server-tests.scala

@@ -4,6 +4,7 @@ package forked.server
 object DocAnnotationsTests extends DocAnnotationsTests(fork = true, clientServer = true)
 object HygieneTests extends HygieneTests(fork = true, clientServer = true)
 object LargeProjectTests extends LargeProjectTests(fork = true, clientServer = true)
+object MillJvmOptsTests extends MillJvmOptsTests(fork = true, clientServer = true)
 object ScriptsInvalidationTests extends ScriptsInvalidationTests(fork = true, clientServer = true)
 object ScriptsInvalidationForeignTests extends ScriptsInvalidationForeignTests(fork = true, clientServer = true)
 object ZincIncrementalCompilationTests extends ZincIncrementalCompilationTests(fork = true, clientServer = true)

integration/forked/src/forked-tests.scala

@@ -4,6 +4,7 @@ package forked
 object DocAnnotationsTests extends DocAnnotationsTests(fork = true, clientServer = false)
 object HygieneTests extends HygieneTests(fork = true, clientServer = false)
 object LargeProjectTests extends LargeProjectTests(fork = true, clientServer = false)
+object MillJvmOptsTests extends MillJvmOptsTests(fork = true, clientServer = false)
 object ScriptsInvalidationTests extends ScriptsInvalidationTests(fork = true, clientServer = false)
 object ScriptsInvalidationForeignTests extends ScriptsInvalidationForeignTests(fork = true, clientServer = false)
 object ZincIncrementalCompilationTests extends ZincIncrementalCompilationTests(fork = true, clientServer = false)

integration/local/resources/mill-jvm-opts/.mill-jvm-opts

@@ -0,0 +1,3 @@
+
+# comment after an empty line
+-DPROPERTY_PROPERLY_SET_VIA_JVM_OPTS=value-from-file

integration/local/resources/mill-jvm-opts/build.sc

@@ -0,0 +1,7 @@
+import mill._
+
+def checkJvmOpts() = T.command {
+  val prop = System.getProperty("PROPERTY_PROPERLY_SET_VIA_JVM_OPTS")
+  if (prop != "value-from-file") sys.error("jvm-opts not correctly applied, value was: " + prop)
+  ()
+}

integration/local/src/MillJvmOptsTests.scala

@@ -0,0 +1,14 @@
+package mill.integration
+
+import mill.util.ScriptTestSuite
+import utest._
+
+class MillJvmOptsTests(fork: Boolean, clientServer: Boolean)
+  extends IntegrationTestSuite("mill-jvm-opts", fork, clientServer) {
+  val tests = Tests {
+    initWorkspace()
+    "JVM options from file .mill-jvm-opts are properly read" - {
+      assert(eval("checkJvmOpts"))
+    }
+  }
+}

main/client/src/mill/main/client/MillEnv.java

@@ -114,7 +114,7 @@ static List<String> readMillJvmOpts() {
         ) {
             while (sc.hasNextLine()) {
                 String arg = sc.nextLine();
-                if (!arg.trim().isEmpty() && arg.startsWith("#")) {
+                if (!arg.trim().isEmpty() && !arg.startsWith("#")) {
                     vmOptions.add(arg);
                 }
             }