Fix Rust target-dir with spaces (#173)

* Enquote all Cargo proj path

* Add a test case

* enquoted => backslashed

* symlink simple cargo with space

Author: pomadchin

plugin/src/main/scala/com/github/sbt/jni/build/Cargo.scala

@@ -32,7 +32,7 @@ class Cargo(protected val configuration: Seq[String]) extends BuildTool {
     def clean(): Unit = Process("cargo clean", baseDirectory) ! log
 
     def library(targetDirectory: File): List[File] = {
-      val configurationString = (configuration ++ Seq("--target-dir", targetDirectory.getAbsolutePath)).mkString(" ").trim
+      val configurationString = (configuration ++ Seq("--target-dir", targetDirectory.getAbsolutePath.backslashed)).mkString(" ").trim
       val ev =
         Process(
           s"cargo build $configurationString",

plugin/src/main/scala/com/github/sbt/jni/build/package.scala

@@ -0,0 +1,7 @@
+package com.github.sbt.jni
+
+package object build {
+  implicit class StringOps(val self: String) extends AnyVal {
+    def backslashed: String = self.replaceAll(" ", "\\ ");
+  }
+}

plugin/src/sbt-test/sbt-jni/simple cargo with space/README.md

@@ -0,0 +1 @@
+../simple-cargo/README.md

plugin/src/sbt-test/sbt-jni/simple cargo with space/build.sbt

@@ -0,0 +1 @@
+../simple-cargo/build.sbt

plugin/src/sbt-test/sbt-jni/simple cargo with space/core

@@ -0,0 +1 @@
+../simple-cargo/core

plugin/src/sbt-test/sbt-jni/simple cargo with space/native

@@ -0,0 +1 @@
+../simple-cargo/native

plugin/src/sbt-test/sbt-jni/simple cargo with space/project

@@ -0,0 +1 @@
+../simple-cargo/project

plugin/src/sbt-test/sbt-jni/simple cargo with space/test

@@ -0,0 +1 @@
+../simple-cargo/test