refactor unit tests on package lock (#374)

* don't use ping to wait for some time
a ping to localhost doesn't necessarily work on some firewalled computers

* fix duplicated tests

* fix tests under windows

* fix linux test by using "exec"

.golangci.yml

@@ -1,54 +0,0 @@
-linters-settings:
-  govet:
-    check-shadowing: true
-  gocyclo:
-    min-complexity: 20
-  dupl:
-    threshold: 100
-  goconst:
-    min-len: 3
-    min-occurrences: 3
-  lll:
-    line-length: 160
-  nakedret:
-    max-func-lines: 20
-  gocritic:
-    enabled-tags:
-      - performance
-      - style
-      - diagnostic
-    disabled-checks:
-      - dupImport # https://github.com/go-critic/go-critic/issues/845
-    settings:
-      rangeValCopy:
-        sizeThreshold: 512
-      hugeParam:
-        sizeThreshold: 512
-linters:
-  enable-all: true
-  disable:
-    - interfacer
-    - scopelint
-    - golint
-    - maligned
-    - godot
-    - gochecknoglobals
-    - exhaustivestruct
-    - wsl
-    - nestif
-    - goerr113
-    - nlreturn
-    - wrapcheck
-    - misspell
-    - cyclop
-    - whitespace
-    - paralleltest
-
-  fast: false
-
-run:
-  tests: true
-
-issues:
-  exclude-use-default: true
-