Fix python version display (#77)

Author: andrask

src/main/kotlin/com/github/pyvenvmanage/VenvProjectViewNodeDecorator.kt

@@ -15,10 +15,12 @@ class VenvProjectViewNodeDecorator : ProjectViewNodeDecorator {
         val pyVenvCfgPath = VenvUtils.getPyVenvCfg(node.getVirtualFile())
         if (pyVenvCfgPath != null) {
             val pythonVersion = VenvUtils.getPythonVersionFromPyVenv(pyvenvCfgPath = pyVenvCfgPath)
-            val fileName: String? = data.getPresentableText()
-            data.clearText()
-            data.addText(fileName, SimpleTextAttributes.REGULAR_ATTRIBUTES)
-            data.addText(" [" + pythonVersion + "]", SimpleTextAttributes.GRAY_ATTRIBUTES)
+            if (pythonVersion != null) {
+                val fileName: String? = data.getPresentableText()
+                data.clearText()
+                data.addText(fileName, SimpleTextAttributes.REGULAR_ATTRIBUTES)
+                data.addText(" [$pythonVersion]", SimpleTextAttributes.GRAY_ATTRIBUTES)
+            }
             data.setIcon(Virtualenv)
         }
     }

src/main/kotlin/com/github/pyvenvmanage/VenvUtils.kt

@@ -27,24 +27,22 @@ object VenvUtils {
     }
 
     @JvmStatic
-    fun getPythonVersionFromPyVenv(pyvenvCfgPath: Path): String {
-        val unknownVersion = "unknown"
-
+    fun getPythonVersionFromPyVenv(pyvenvCfgPath: Path): String? {
         val props = Properties()
 
         try {
             Files.newBufferedReader(pyvenvCfgPath, StandardCharsets.UTF_8).use { reader ->
                 props.load(reader)
             }
         } catch (e: IOException) {
-            return unknownVersion // file could not be read
+            return null // file could not be read
         }
 
-        val version = props.getProperty("version_info")
+        val version = props.getProperty("version")
         if (version != null) {
             return version.trim { it <= ' ' }
         }
 
-        return unknownVersion
+        return null
     }
 }