Correctly handle scenarios when the symbol isn't used

lib/guru-utils.js

@@ -4,7 +4,7 @@
 import path from 'path'
 import {getEditor, getCursorPosition, isValidEditor, utf8OffsetForBufferPosition} from './utils'
 
-const scopedModes = ['callees', 'callers', 'callstack', 'pointsto', 'whicherrs', 'peers']
+const scopedModes = ['callees', 'callers', 'callstack', 'pointsto', 'whicherrs', 'peers', 'referrers']
 
 function buildGuruArchive (editor: any = null) {
   let archive = ''
@@ -27,13 +27,15 @@ function computeArgs (mode: string, options: ?{gopath: string}, editor: any = ge
   const filePath = editor.getPath()
   const args = ['-json']
   if (scopedModes.includes(mode)) {
+    const src = 'src/'
     let relPath = atom.project.relativizePath(filePath)
     if (relPath && relPath.length > 0 && relPath[0] !== null) {
-      // Make it relative to GOPATH because guru tool requires it.
-      if (options && options.gopath && options.gopath.length) {
-        const scope = path.relative(options.gopath + '/src', relPath[0] + '/...')
-        args.push('-scope', scope)
+      let scope = relPath[0]
+      const srcIndex = scope.indexOf(src)
+      if (srcIndex != -1) {
+        scope = scope.substring(srcIndex + src.length, scope.length)
       }
+      args.push('-scope', scope + '/...')
     }
   }
 

lib/usage/usage.js

@@ -76,11 +76,7 @@ class Usage implements PanelModel {
   }
 
   parse (obj: Array<Object>): ?Object {
-    if (!obj) {
-      return undefined
-    }
-
-    if (obj.length < 2) {
+    if (!obj || !obj.length) {
       return undefined
     }
 
@@ -107,7 +103,7 @@ class Usage implements PanelModel {
     if (state === 'running' || state === 'error' || state === 'initial') {
       props.content = content
     } else {
-      if (!content || !content.packages) {
+      if (!content || !content.packages || !content.packages.size) {
         props.content = 'No usage found...'
       } else {
         props.content = {