feat(walking): support for partial walks, early exits, faster diffs

(cherry picked from commit e47262abc1c5671673afe3ff4dccf7044c9f612c)

Author: estrattonbailey

index.js

@@ -3,12 +3,17 @@ const path = require('path')
 const graph = require('../')
 
 const cwd = path.join(__dirname, '/fixture')
-const w = graph({ cwd, alias: { '@': cwd } })
 
+console.time('bench')
+
+const w = graph({ cwd, alias: { '@': cwd } })
 w.add([path.join(__dirname, '/fixture/index.js')])
+console.log('modules', w.ids.length)
+w.close()
 
-console.log(w.ids.length)
+console.timeEnd('bench')
+process.exit()
 
-w.on('change', ids => {
-  console.log(w.ids.length)
-})
+// w.on('change', ids => {
+//   console.log('change', w.ids.length, w.tree)
+// })

test/bench.js

@@ -0,0 +1,3 @@
+import b_a from './b_a'
+
+export default 'b'

test/fixture/commonjs/a.js test/bench/commonjs/a.js

@@ -0,0 +1 @@
+export default 'b_a'